What is the Best Synthetic Oil?

121 Comments

1. Not a comment, but a question (sorry if it was already addressed in the discussion thread), I have around 20 quarts of Mobil Jet Oil 254 (fully synthetic) for aviation use, that has recently expired. Could it be used in vehicles that usually take 5w30 fully synthetic oil (Like Mitsubishi Outlander /Renault Duster), or is that not a good idea? A bit difficult to compare the specs….the 254 is used for turbine engines…thanks for any authoritative answers: – ).

   • Hi Craig:
     I’m glad you asked as you cannot use Mobil Jet Oil 254, a synthetic aviation turbine oil, in a gasoline engine. It does not have the required additives such as detergents, dispersants, antiwear and overbased to manage the byproducts of an internal combustion engine. You will need to purchase an engine oil that meets your cars API and/or ILSAC specification. Happy motoring.
     Cheers
     Gary

     • Hi Gary, Thanks for your reply. The aircraft that uses the 254 oil burns jet A1 Kerosene (similar to diesel, but without the lube). The vehicles I was thinking of using it for are both diesel. The difficulty is comparing the car’s specs with the aviation specs (probably totally different testing parameters), pity there isn’t a comparison chart. Anyway, I’ll go with your advice that confirms my hunch that it would be a risky business: – /. Thanks again Gary: – ).

2. I have a 2005 Toyota Sequoia SR5 v8. What is the best synthetic oil should I use?

   • Hi Jon:
     You must luv your 2005 Toyota Sequoia as you still have it! 🙂 I had to do some research on your SUV as not a familiar model to me but have found a full synthetic engine oil from Mobil that should be suitable. It is Mobil 1 5W-30 ‘Newer Vehicle Formula’ which meets the Toyota requirements for preferred Viscosity (SAE 5W-30) and Industry Performance ILSAC GF-5. Don’t forget to change your oil-filter also and take into account the extra oil needed. Happy motoring!
     Cheers
     Gary

3. Which of the Mobil 1 products do you believe are Group IV in North America? Who does testing to determine the composition (i.e. the Group composition percentages) of the product?

   I’ve been reading a lot of sites saying that after the Castrol win, all of the commercial products labeled as “synthetic” are really Group III in North America and that only in Europe and Asia are they forced to use Group IV if they label as synthetic. Is this true?

   The implication is that the same product i.e. Mobil 1 Extended Performance, sold in Europe is Group IV while in North America it is Group III. Just wondering if you can shed any light on this issue.

   Thanks.

   • Hi Pete:
     You ask a very good question as it is one a techo like me struggles with since as you correctly state the Castrol “win” changed the scientific objective definition of “Synthetic” Base Oil to a non-scientific subjective inclusion. It used to be Group IV PAO’s (polyalphaolefins) and Group V (Esters etc) but now includes Group III (Hydrocracked Base Oils). Problem is, the Marketers have taken over and can claim “Synthetic” for Group III and can use this claim whilst using less costly base oils. I understand this “synthetic claim” is Global, so includes Europe, Asia and the USA. The problem is that looking at engine oil marketers no-one, not one that I have researched, states exact base oil composition today. What maybe we have to do is filter thru the marketing “bullshite” and relate to who has the long term historical research & development to manufacture the actual base oils including all Group I, Group II, Group III, Group IV and Group V and then formulate engine oils with synyagestic chemistry and maybe not off-the-shelf commercial packages. Then, bottom line – actual performance. One company I know that does that is Mobil…that’s why I put them at #1
     Cheers
     Gary

4. I used to run Mobile1 Synthetic in everything. Then I came across an independent oil tester, that tested film and shear strength of oil, on over 200 blends of different brands. His test showed Mobile1 synthetic performed very well at normal operating temps, but when the temps rose by 40°, the protection of Mobile1 dropped by 36%.
   Since then, I now run Amsoil Signature Series 5w30, as this oil out performed every oil in his tests.

   • Hi Jim:
     Please provide name of tester and actual test method plus actual results then I might look further!
     PS The product is Mobil 1

5. Unfortunately, you did not list or recommend the best two synthetic oils, both Group V base stock, Red Line and MOTUL. And, Mobil 1 as now formulated since losing their law suit against CASTROL, now uses some Group III base stocks.

   • Hi James:
     Yes you are correct that since Mobil lost a court case to Castrol allowing Group III base oils to be claimed as “Synthetic” then many, many engine oil marketers are using Group III and claiming “Fully Synthetic”. However, which oils by Red Line & Motul you believe are 100% Group V (ester). I suggest as they do not manufacture base oils, they buy then blend their oils as every blender/marketer does. My experience is that maybe some 2-Stroke engine oils and Jet Engine Oils are 100% Ester, not commercial engine oils –> by the way I still understand the biggest manufacturer, blender & marketer of Group V Jet Engine Oils is ExxonMobil.
     Cheers
     Gary

6. This is either a joke or a Mobile 1 marketing page. Amsoil > Royal Purple > Nearly every other synthetic oil out there > Mobile 1. And it’s not even close. Look at the research and don’t believe the hype about Mobile 1.

   • Hi Adam:
     The product is Mobil 1.
     Cheers
     Gary

   • Most are not true synthetics, they are just able to advertise it as such due to loopholes. Look for a Group IV based motor oil. I do not believe in extended oil changes due to the fact that most filters are junk with the higher price brand names being the worst offenders. Also, how many have you known that have blown and engine, tranny, gear set, etc over frequent fluid changes? I have worked for several shops who have promoted Mobil 1 with 5000 – 10000 mile oil changes and they all started burning oil prior to their next oil change. I love Mobil 1, but it is really a more refined conventional motor oil. Bought a used truck with sludge covering the cam shafts, 2 Mobil 1 changes later the sludge was pretty much gone. I have swithched back to a conventional oil as it performs every bit as good as Mobil 1 with the proper oil change interval (3000k) and a quality filter (not a Bosch, Mobil 1, K&N, and will never use a fram). I’ve cut open many filters, and believe it or not, my last cut was on a STP and it had more filtration than the fancy brands. I personally use OEM Toyota filters or Napa Gold when my Toyota stock is depleted.

     As for oils, people need to realize that dealers use the cheapest oil available at the time they order it. 1 oil change you may get Pennzoil, the next may be Kendall, and the next could be a no-name brand. I have seen it and even called dealers looking for oil recommendations on exotic cars and have been told they were using a bulk packaged conventional oil one high end vehicles that called for synthetic oil.

     Take this info for what it’s worth. I hope it provides something useful to someone, and will help people who are concerned to do further research.

     Ryan

     • Hi Ryan:
       I agree with you that Group IV PAO based synthetic motor oils are the best.
       Cheers
       Gary

   • I like Mobil 1. Bought many used cars that had a lot of sludge and after a couple of oil changes it did an excellent job of decreasing the amount of sludge rapidly. After that I would switch to conventional oil. To my knowledge, Mobil 1 extended performance, Amsoil, and Royal Purple should be group IV. I know I am missing many, but it isn’t too important what oil you use, but how you change it. I’ve quit several shops because they were using Kendall Synthetic Blend in everything, regardless of what to manufacturer recommended or the customer asked for. Had a Corvette customer ask me once why I charged him so much for an oil change, told him “You wanted Mobil 1, and that is what the manufacturer calls for” he god pissed about never having to pay that before but didnt realize he had been running Kendall 5w30 blend which was the bulk oil. I walked out the next day, I’m not going to BS people, and these types shops are more common that good shops. If I wouldn’t do it to my car then I will explain why they shouldnt do it to theirs.

     • Hi Ryan:
       Yep, Mobil 1 can clean up dirty “engines” but I would continue to use it for protection against wear and keeping it clean.
       Cheers
       Gary

7. Mobil 1 —- Have used since it came on the market. Change oil ? not something I am concerned about. Jim

8. You know, you guys should at least mention filter changes in between oil changes. Super oil synthetics don’t mean a thing if they are full of grit and carbon. No way am I going to risk a $10K engine on a 10K miles oil change.

   • Hi Jon:
     Yes you are absolutely correct that oil filters should also be changed every oil change but not in-between and air filters should be checked at the same time and changed according the manufacturers recommendations. However, if you drive in desert or dusty conditions all the time then maybe you should be changing your engine oil, oil filter & air filter every 3 months?
     Cheers
     Gary

9. I don’t see any actual testing here. 99% of so-called “Synthetic” oil made in the USA has no synthetic base. Redline and AMSOIL Signature are Group 4 with PAO base. Rumors are that Royal Purple was sold to Bel-Ray/Calumet a few years ago and is no longer a Group 4. The terms “Synthetic” , “Full Synthetic” and “100% Synthetic” mean nothing in the USA. They are just marketing terms. German-made oil, if labeled “Synthetic”, must by law be Group 4 real syuynthetic. Castrol is responsible for the industry downgrade in 1997 to Group 3 by being able to call a hydrocracked Dino oil “Synthetic” with no PAO base. Don’t pay over $6.00 a quart for an inferior Group 3. You can buy O’Reilly syn for about $3.50 a quart. Mobil 1 and Castrol Edge are merely Group 3 in the USA. Don’t be fooled. Know the difference between Group 3 and Group 4. It’s the only difference in oil. Not Grade and not API classification. This is a true automotive conspiracy.

   • Best note ever!

10. My understanding about synthetic oils is that the synthetic part is just the selection of oil molecules for uniformity and that the longest chain molecules give the best Poisson’s ratio. What bothers me is the marketing trickery and nausea. I think that it would be the best marketing strategy, to tell the truth, and put a label on the side with contents and references to MilSpec or NIST specifications. Platinum indeed. Who comes up with this crap? Some anemic Englander? In any case, if it is good enough for FIAT it is good enough for anything I own. Among the Mobil One choices, my Toyota trained technician said that only one of the Mobil One oils is actually full synthetic but I don’t remember which one.

11. I dont see any mention of motul which is a type iv recommended alot with Audis, Subarus and vws. And lucus oil and redline for that matter since amsoil wass brought into this study and were talking about “oil performance”

12. BMW and Mini are not pensoil factory fill, I know this as a mechanic for over a decade that Castrol is filled from day one and even says so on the oil cap. I used Mobil 1 due to price on my Audi A6 4.2 and it burned a quart more between oil change than did Castrol 5w40. I’ve used Mobil 1 on many vehicles including my mom’s 2.4 Honda Accord 0w20, it also used more oil between changes than did pensoil, which she has been using because she won’t top off, with pensoil it’s not been necessary. Though it’s a great oil it being #1 is opinion not fact here. If I rated them I might reorder what going on here.

    • Hi Justin:
      First of all sorry to take a while to respond but my computer had a hardware issue and I needed to replace. I’m OK that you want to challenge my #1 and on-going order but mine was based on technical & objective knowledge re engine wear and engine deposits etc. You seem to refer to subjective oil-consumption that Mobil 1 “burned more”. From my experience measured high oil-consumption “burning oil” is due mainly to 2 reasons with many factors –> engine condition ie worn engine, cracked ring/s, leaking seals, maintenance with fuel dilution, oil-filter and wrong oil ie too low viscosity, low quality, incorrect oil-change etc.
      I’m sorry but without full details of your vehicles and their condition ie from brand new and when serviced and what viscosity of all the oils, I cannot technically agree with you that Mobil 1 “burns” more oil and a one-to-one basis?
      Cheers
      Gary

13. I generally never buy synthetic oil blends because I’m suspicious of them. I don’t believe I’ve ever seen one that stated what percentage synthetic oil it contained. It could be only 20% synthetic and they could still legitimately sell it as a synthetic “blend”. Do you have any information about this, or has any testing ever been done? Thanks.

    • Hi Jim:
      You are absolutely right! Unfortunately oil marketers do not put on the label nor on their technical data sheets any information about the type of base oils they use. The only indication is that a “full synthetic” should contain 100% of API Group III and/or IV and/or V base oils. A “Semi- or Part-Synthetic” should contain ‘some’ Group III, IV or V but mainly API Group 1 and/or 2 Conventional Base Oils. “Some” could be very low percentage as you state. Laboratory testing can be done to try and determine this but results are usually kept “in-house” and not published. Once you select a “Full” or “Semi” synthetic motor oil, before buying you could ask the marketer what base oils they actually use. I think they may answer as I have – ambiguously. Look for performance claims and well know brands.
      Cheers
      Gary

14. I am sorry to be the bearer of bad news but to be very clear ( where you were very ambiguous) Mobile has not used Group IV base stocks since Castrol prevailed in their law-suit in the ( I think 1990s) This has allowed Mobile to use the same cheaper Group III stocks as Castrol and still compete on price. The current Mobile 1 synthetic oils everywhere (except Germany) are made with Group III base stock. Todays Worldwide Mobile synthetic oils would not perform in the frying pan like it did in the 1970s… ( except in Germany ). German law is if you advertise full synthetic then you by golly have to provide real Group IV base stock oils. Consequently none of todays North American Mobile 1 oils have the extreme hi temperature resistance nor the super extended resistance to viscosity breakdown that existed in the 1970s. Please go back and correct your info concerning Mobile and the composition of Mobile 1 oils in this website. All you said wwas that Mobile knows a lot about oils and manufactures some base stocks but that is not the same thing as stating they use all their inhouse manufactured base IV stocks in their domestically supplied auto motor oil products called Mobile 1. In fact most of their advanced oil expertise is used in providing aviation FAA certified turbine lubricants.

    So, as far as I know, in order to get the true hi temp longevity and viscosity longevity/ resistance to viscosity loss for extended durations beyond Group III oils ( extended film strength resulting in reduced wear) ) of lubricants made with Group IV base stocks, you have to either acquire German supplied Mobile 1 auto oils or Amsoil.

    There is a possibility (that I have not confirmed yet) That Redline is a company that may also be using true Group IV base stocks in their marketed motor oils.

    • Hi Scott:

      Normally I would not reply to ‘statements’ like yours…but this time I will, very briefly.

      When you state Mobile, I assume you mean Mobil…this is a classic example of a person ignorant of Brands and history particularly technology.

      When you state you are the bearer of ‘bad news’ – with no statement of your personal credibility nor expertise…I must assume yours is ‘fake news’!

      I restate that as far as I know Group IV PAO’s are still used in Mobil 1 globally.

      I restate that Mobil (ExxonMobil) I understand is the only oil company manufacturing & marketing Group I, Group II, Group III, Group IV and Group V Base Stocks.

      I understand that Amsoil & Redline buy base stocks, additives and are therefore blenders/marketers.

      When you fly, I still understand that 90% of the world’s Jet Turbine Engines are using ExxonMobil Group V synthetic base stocks since the 60’s. So when you fly you should feel comfortable.

      Cheers
      Gary

      • “I restate that as far as I know Group IV PAO’s are still used in Mobil 1 globally.”

        Does that mean that you haven’t had confirmation from Mobil? Unless we get some statements from Mobil or someone able to test for it we shouldn’t assume anything.

        • Hi Jeremy:
          As far as my research goes no oil marketer provides exact technical confirmation of the base stocks used in their products – all provide marketing statements which are very subjective.
          Let me restate that as far as I know Group IV PAO’s are still used in Mobil 1 globally.
          Cheers
          Gary

15. Hi Gary, I’ve been using Mobil 1 since purchasing my first new Silverado in 1991. I remember Mobil advertising “one year or 25,000 miles” oil change intervals at first but discontinuing those ads. I looked into it and a mechanic told me that they stopped because some people had voided their new vehicle warranties by exceeding manufacturers’ recommended change intervals. The thing that originally sold me was the frying pan test where they cooked both conventional oil and Mobil 1 side by side on a range. The conventional turned to a burnt sludge while the synthetic never burnt or changed its appearance. Doing my own oil changes I’ll gladly pay a few extra bucks to extend the intervals saving me 2 or 3 changes per year.

    • Hi Giuseppe:
      Happy New Year! Great to hear from you sharing your Mobil 1 story – many thanks. You are a long=term user. Congratulations I’ve been using Mobil 1 since 1974 when it was first developed in all my cars, bikes and lawnmowers since! Yes, some vehicle manufacturers were very strict on service intervals re warranty. However, from my experience, no-one using Mobil 1 had an oil-related issue. But, best to conform with new vehicle warranty requirements as regular servicing is also a major safety issue checking everything else like water & brake fluid levels, tires, brakes, lights, battery, electronics etc. Yes, I agree the advertising of the ‘frying pan test’ was great in demonstrating the significant thermal stability of Group IV/V PAO/Ester Fully Synthetic Base Oils against Group I Conventional Mineral Base Oils in an engine oil. Combined with synergistic additives allowed significantly extended oil-drains and engine protection. I believe Mobil 1 was 20 years ahead of the competition way back then and maybe still remains the benchmark engine oil till this day?! I also sill use Mobil 1 to this very day changing annually. Happy motoring 🙂
      Cheers
      Gary

    • Because Mobil one was 100% synthetic then they pulled a bait and switch calling it full synthetic which barely meets manufacturer guidelines do more research AMSOIL is 100% synthetic this guy must be working for mobile one

      • Hi AJ:
        Not sure where you got your information nor understand that you state “…Mobil 1…barely meets manufacture guidelines….” also not sure of your 100% claims for both Mobil and Amsoil?
        Please explain.
        Cheers
        Gary

      • A,J I completely agree with your statement! he does have a “thing” for mobil 1..lol but what kills me he thinks it’s better then AMSOIL, mobil 1 if I remember right tests it’s own oil where AMSOIL has a 3rd party conduct unbais results but i would put his mobil girlfriend to my big daddy AMSOIL head to head!!

16. Hi Gary. I have a 2008 Nissan Frontier V6 4×4. I’ve used Mobile 1, Extended Performance 15,000 mile 5W-30 since I bought it new. It only has 32,000 miles on it. And I just bought a 2017 Toyota Camry for my wife, it has about 400 miles on it. It takes 0W-20 oil, and the new cartridge type oil filters. Here is my question; between my truck and my wife’s car, we drive very few miles per year, approximately 4,000 miles on each vehicle. So we have only been changing the oil on them once a year. Is this enough? Also, at what mileage should I do the first oil change on the Camry? And, I had planned on using 0W-20 Mobile 1 extended performance oil in it, but recently I have been wondering about Amsoil, because they state that it’s 100% synthetic, meaning it’s true synthetic, thus better than full synthetic. I’m confused about this, what do you think? Also what’s your opinion, on how I’ve been changing the oil?

    • Hi Ron:
      Great to see that you are already using Mobil 1 Synthetic engine oils – I reckon the best. Amsoil is also a great brand and use synthetic base oils. Key reason I have Mobil as #1 and Amsoil as #2 is that Mobil (ExxonMobil) actually research, develop & manufacture base oils, including synthetics. Amsoil buy their base oils from someone else so are blenders – key difference I believe. So suggest you can stay with Mobil 1 with confidence you have the best. Because you drive only 4,000 miles in each vehicle each year, I need to ask a couple questions –> are mostly your trips very short say just a few miles regularly or the occasional long run 100 miles or so? Reason is that lots of very short trips are not good as gasoline fuel dilution, water contamination, engine deposits, engine wear become serious issues and stress on an engine oil as it doesn’t come up to optimum temperature and operating time. If all your trips are “short”, then I would suggest changing both oil and filter every 6 months plus include a long run every month at highway speed for at least 1 hour. Then try a spot of fishing or lunch somewhere at a beaut diner 🙂 I would change the oil in your new Toyota Camry at your scheduled first service with your dealer for warranty then move to every 6 months . I would also suggest you should stay with Mobil 1 Extended Performance 0W-20 for both vehicles as you have had almost 10 years experience with Mobil 1 already.
      I luv someone who looks after their vehicles like you do. Wish you many, many years of happy and safe motoring.
      Cheers
      Gary

    • Hey Ron unlike Gary who can’t open his mind up to understand that Amsoil is by far the best 100% synthetic not full synthetic like mobil 1 now I don’t have a problem using mobil 1 but remember what mobil did with its 15,000 mile oil they retag the 15,000 and put 20,000 mile Guarantee on the new bottle then raised the price they must think customers are stupid! And mobile one does all of their testing in house how can that be a bias report now Amsoil has a 3rd party who conducts these test and are completely bias, that’s a fact Ron. I have been driving over 30 years using nothing but Amsoil with no major engine problems, in fact one of my cars is a old 2001 Chevy SS LS1 with 302,489 original miles nothing replaced except tires, batteries, e.t.c . My last statement is Mr Gary talked about Amsoil outsourcing their base oils, no company will divulge that info but let’s go with it go online and see actual test done by a third-party on about I believe there’s like 12 to 13 different companies being tested and Amsoil ” with their outsourcing” still beats the pants off of every oil they tested.hope you make a good choice my friend

17. Witch oil for 201q vetted period in mobile brand thanks

    • Hi Steve:
      Can’t quite understand your question. Please retype & resend.
      Cheers
      Gary

18. gary…looking for a good 5w20 fully synthetic oil for my new 2017 jeep willys wrangler. additionally will any filter work with synthetic oil..any recomm on this also?

    thanks

    • Hi Robert:
      You didn’t mention your engine but I researched and understand it is a 3.6 litre V6 24 valve VVT gasoline fuelled. What an awesome looking vehicle – luv it. Checked the engine oil specs as yours is brand new so need to ensure you meet warranty requirements if applicable. You are correct as you require an SAE 5W-20 engine oil but also needs to meet Chrysler MS-6395 specification. The following claimed “fully synthetic” engine oils I understand meet MS-6395 in the sort of order of my preference but brand your choice based on your experience –> Mobil 1, Royal Purple, Pennzoil Platinum, Castrol Edge, Valvoline Synthetic and Quaker State. Re oil-filters, doesn’t matter if fully synthetic or not, but has to be good quality so suggest stay with Jeep (Chrysler) factory brand during warranty period.
      Great off-road driving/experience with your new ‘toy’ – a tad jealous!
      Cheers
      Gary

      • gary, regarding my 2017 jeep willys wrangler (3.6 litre Pentastar, V6 VVT engine) just learned Mobil 1 does not meet Chrysler ms6395 requirements.

        in next couple days i will change the oil for the first time (will use full synthetic). i bought some factory Mopar filters. will need to decide on oil …..penzoil platinum, castrol edge or valvoline syn

        thanks

        • Hi Robert:
          Happy Thanksgiving. Good to hear from you again. I luv Jeeps, particularly Wranglers as they look great. You are right, Mobil 1 has not received Chrysler MS6395 requirements, and to be honest I do not know why? However Mobil Super Synthetic 5W-20 does meet MS6395 and is also the recommended viscosity grade. Along with other SAE 5W-20 ‘synthetic’ marketing claims but being Group !!! base oil technology as you mention Pennzoil Platinum, Castrol Edge or Valvoline Syn based on your fav brand by experience, race car promotion or advert ’tis your choice – mine would be Mobil Super! Happy motoring in your new Wrangler. Remember to change the oil and filter at recommended service intervals.
          Cheers
          Gary

19. I started using Mobil 1 oils while stationed in Dover Deleware approx 39 years ago. I have purchased approx 9 new vehicles over the years, and I have gotten over 300.000 miles on each of them with no major engine work on any of them. My current truck that I own now is a 2003 Chev PU with a 5.3L v8 with 360,000 miles. Runs like new. I’m thinking about changing from Extended oil to Annual oil.
    I am a true believer in Mobil 1, and I enjoyed reading your documents and test.
    Thanks
    Coral

    • Hi Coral:
      Fantastic experience with Mobil 1 and so many thanks for sharing. I have had exact same experience but I beat ya a little bit as go back to 1974 although it was called Mobil Syn back then. Guess you and I will be using Mobil 1 forever for protecting your engine like new 🙂
      Cheers
      Gary

20. Gary,

    I have a 2014 BMW F800GS motorcycle. It has a Rotax engine with all the modern stuff including a catalytic converter. The manual recommends: SAE 15W-50 API SM JASO MA2 Turns out, this is a hard oil to find. The dealer sells a BMW branded, “Advantec” oil, which I’m told by the dealer is semi-synthetic. I can’t find on the label who actually makes it. The closest dealer is over 60 miles away which is a long way to go for a quart of oil. The local bike shop sells a fully synthetic oil with the exact same specs made by MotoRex. My question is: can I mix these? If so can I go either way with the mix: top-off with the MotoRex on an Advantec oil change; or top-off with the Advantec with a MotoRex oil change? That may sound convoluted but I’m heading off on a 6000 mile journey to Canada and want to go prepared, knowing I’m not going to find this stuff on the road.

    Andy

    • Hi Andy:
      Key for you to protect your wet clutch and perfromance as sharing the engine oil is JASO MA2. Plus suggest stay with minimum recommended oil changes as you will be switching no matter what brand but JASO MA2 is strongly suggested for every oil change so pack an extra bottle in your pack. Going from “full synthetic” to “semisynthetic” dilutes the overall engine cleanliness potential so that is why I suggest change oil at manufacturer recommended service intervals. And yes – all engine oils re API SM etc are compatible but for wet clutches, you need JASO MA2 also.
      Cheers
      Gary

      • “Going from “full synthetic” to “semisynthetic” dilutes the overall engine cleanliness potential…”

        Gary,
        Your statement above does not take into account the various detergents like magnesium and calcium sulphonates.

        Andy,
        Unless otherwise stated on the bottle, all oils of the same viscosity and SAE/JASO ratings can be mixed without worry. Love those 800s, keep it shiny side up!

        J

        • Hi Jeremy:
          See you are back again – you must be an expert and would luv to know your background, education & experience please?
          If you are an expert then you would know the synergistic contribution of all the base oils Group I, II, III, IV & V and additives such as all detergents, dispersants, antiwear, oxidation inhibitors, friction modifiers, pour point depressants, viscosity index modifiers etc plus all the API, ACEA, ILSAC, JASO etc engine and material tests?
          However, all being the same, going from full synthetic to semisynthetic base oils does have the potential to increase deposits in an engine – do you agree as you are an expert?
          Re your last statement, careful as viscosity is classified by SAE but JASO is Japanese for engine performance and suitability. It is misleading to state ‘all oils of the same viscosity can be mixed’ because the engine performance requirements are covered by API, ACEA, ILSAC, JASO etc.
          Cheers
          Gary

21. Hi Gary,
    I found your website and your comments to be very informative. Clearly your top choice of synthetic motor oils is Mobil One.
    You mentioned your number two choice as Amsoil. Oddly enough, your comment was preceded with, “Not sure, but still believe they buy all their Base Stocks and then blend with purchased additives?”
    If you are “not sure” if Amsoil byes or uses “Base Stocks” in their products, why would you make such a misleading, uninformed and uneducated statement?
    My research (along with direct contact with Tech department of Amsoil) indicates that Amsoil has NO “Base Stocks” in any of their “Signature Series”, it is NOT blended with any petroleum products and it is 100% purely synthetic.
    To support that statement, Amsoil is the only company that offers a 25,000 mile guarantee on their “Signature Series” of lubricants.
    I’m curious Gary, does “Mobile One” or any other oil company offer such a guarantee?
    I will look forward to your response,
    David
    PS:Just to be transparent, I am not an Amsoil representative in ANY way shape or form. Since I am a notorious cheap skate, I only seek the facts that will help me get another 500,000 miles on my vehicle.

    • Hi David:
      Sorry to confuse –> Base Stocks refer to all API Groups I, II, III, IV & V. I understand Amsoil buy all their base stocks from someone whilst I know Mobil (ExxonMobil) manufacture all.
      Cheers
      Gary

22. Hi Gary,

    Just a comment and some opinions too, on a post a while back about the Honda Civic transmission oil OEM change. As far as using OEM auto trans oil. We have the Magnuson-Moss Warranty Act that allows the buyer of the car to use any oil in their car as long as it is an “equivalent” oil. The manufactures can’t demand the use of their oil to qualify for warranty, otherwise the Magnuson-Moss Warranty Act would kick in and they would have to provide that “warranty oil” for free. Do not believe any dealership person when they say you have to run their oil for warranty. When they do say that, you just found a person who is following company dogma, or a person who does not know what he or she does not know.

    The different oil you would use doesn’t need to be “certified”, because no manufacture will ever “certify” another brand oil other then their own. You would check the other oil manufactures oil and see if they say you can use this oil in place of the OEM oil. You can find out if the oil is “equivalent” or (BETTER) by looking on the bottle and or website of the oil manufacture if they have approved the use of the oil to match or beat the OEM spec oil.

    I think 75% of OEM ATF oils are sub standard for anything other then grandma driving scenarios. I bought a 2014 Rav4 lease return from a lady from upstate New York and there had been zero sign of hauling/soccer mom use in the rear area, and having completely burn’t Toyota WS @22,000 miles when I dumped it. I had a hobby Audi repair shop and have done many ATF changes and I have never smelled such burn’t vial ATF in my life. Toyota WS is a horrible ATF oil, a sub standard semi synthetic, grubbed off as a full synthetic by many. Honda DWS is not much better, all 3 of my Honda’s are rid of that sub standard ATF too. I will only use Redline Group 5 ATF in all my cars and when I will be forced to buy a new car with a CVT I will be using Redline Group 5 CVT fluid too. Transmission oil really needs to be Group 4 to Group 5 as far as I see it. Hyundai as of 2013 1/2 now uses a Group 5 ATF in their ATF pumpers as OEM.

    Why do these car manufacture use cheap sub standard AFT and CVT oils as OEM when the down sizing of transmissions puts such a “load” on them? They say on some ATF pumpers they are “lifetime oil’ when in reality they need to be drained at least by 40,000 miles and when used in even a mild rough use scenario at 30,000. ISO 4406 particulate counts alone justify dumping early, especially on factory fills that have break-in particulates.

    **As an added note**, if your readers plan to do their own transmission changes watch out for “dipstickless” transmissions and do extensive research on the filling and final fluid level process. Many transmissions like Toyota Aisin branded trans have to have their trans fluid level checked by opening the drain plug that has a factory inserted fluid height straw in it, that allows an over filled trans to dump excess fluid to a proper set level of the top of the inserted straw, and an under filled trans doesn’t let anything drain at that critical temp range. So more ATF needs to be added. This has to be done ONLY while the car/truck is running in neutral and trans oil temp is at between 104 to 118 degs. Very easy to do, but you have to follow specific directions.

    • Hi Tom:
      Many thanks for sharing your expert comments – much appreciated and welcome as great to hear from others passionate about oils. You are so right about ATF’s and CVT’s, they are very special re engineering design and lubrication requirements. They can be so different that one ATF would be a complete disaster if used in a transmission that had different friction requirements! I recall that issue with Ford and GM many years ago where in the end they developed industry specifications for ATF’s being Ford MERCON and GM Dexron. At the same time, the Japanese OEM’s were developing OEM specific ATF requirements using proprietary in-house tests making it very difficult to get an oil approved by them. Yes, I’ve been around that long ago! 🙂 This is why I find it very difficult today to suggest or recommend a specific brand of ATF as depends exactly on the motor vehicle you have and the oil specification required by the OEM for their specific transmission in that specific model. Hence I suggest refer to the OEM or an expert like yourself who service transmissions. I always have my transmission/oil inspected by the OEM Dealer/Servicer as required by their service book. You are also right, most if not all today are ‘fill-for-life’ under normal driving conditions – guess that means ‘under full and/or extended warranty’? My past experience has been that they must use very good quality base oils from oil companies, synthetics being the best and latest technology additives from very specialised chemical companies but still they try and keep the cost down so a balance between performance & cost for factory-fill.
      Cheers
      Gary

      • Hi Gary,

        Sorry I got your name wrong, change it please. Also DWS should be DW1. I understand you have to be very careful on what you say hosting a site. I guess I would have to quench my opinion too if I owned the site. But now being a maintenance guy at a medium sized print shop and dealing with oil requirements for our 3 rotary screw air compressors, one being a problem child with hot spots or yet to be found micro dieseling oxidizing and varnishing. The PAO (group4) based OEM oil I have had to “one up ” to a after market high end POE (group 5) to try to combat a warranty issue that the manufacture says is a non issue and has discounted my MPC varnish tests that showed very high readings and very high ISO particulate readings that are basically particulates of varnish that should not be there. Not to mention their bad micron rated filters.

        The oil’s base oils are critical in anything under hard use or in the case of our Toyota Rav4 that only has a “oil heater” and not an added oil “cooler”. The cooler is added to most Lexus’s being a premium Toyota sub company and there for has a reduced stress load on their WS transmission fluid.

        I work close with an Ex Allison transmission oil engineer that has been said to be the “Godfather” of the Allison transmission and he too has opened an oil analysis firm too, subbing out to Polaris Labs. You may know him too, I would guess.

        Why I state this is, you commented about transmission oils being so critical between applications, they are actually not as far apart as you would think. As far as ATF and not CVT which is it’s own specific animal. Here, I will state these are my and quite a few other peoples opinions and NOT yours as a site provider.

        Way before myself getting deep into oil as a part of my job and my connections with industrial oil R&D chemists I went by others on car forums that were testing on their own. When I made industry connections I asked many questions on oil and different scenarios with cocktailing oils to get a good long term outcome. This first started with Honda Odyssey’s auto transmissions that were failing because the Z1 Honda was providing was some of the worst badly designed ATF on the market. Found to be mainly a Group 2/3 combo and way over packed with slip agents. A really bad combo, low quality oil that can’t take high heat and a high slip agent additive quantity that made the trans shift with butter smooth shifts that could not really be felt, but created a massive amount of heat from a slipping clutch pack .Add to this the Oddessy was using a Acura TL car transmission too. A self fulfilling prophecy of destruction, as it did.

        Many owners used Redline or Amsoil ATF and added those brands racing or Type F ATF (Ford Mercon) that those Ford trans speced out no “slip agents”. That seemed to solve or highly reduce the Honda Oddessy trans problems for many.

        I still to this day add 30 to 40% Type F or Racing ATF of Redline to all my Honda and Toyota ATF pumpers. Because I want to keep the viscosity the same as Redline’s D6 ATF that is the low viscosity mileage ATF that everyone is specing out. I do this because I still think all manufacture want to give you too soft and subtule of a shifting trans for my hard use driving style. I have to cocktail racing regular and light weight racing to get a close viscosity to match the speced Redline D6. Of coarse, you add any slip agents to a type F trans and then you will have problems , but going the other way in a Toyota WS and Honda DW1 trans has been time tested as not an issue. I went over with this with my Allison oil engineer and he did not have a problem with it, infact that is the way they do it when they have to test and alter an in use special case use. He said you just want to stay with the same brand so you have the same base oils and add-packs even though most high end ATF brands that spec for use for say Toyota WS and Honda DW1 live well together.

        • Hi Tom:
          Many thanks for your further comments and sharing your experience. Great to receive. Appears like you do have a severe/hard driving style and/or are into racing. These extreme conditions may adversely affect a Factory Fill ATF and possibly shorten its life? My experience with racing is that the only way to provide adequate protection under racing for all lubricants (engine, transmissions, gear, diffs etc is to develop special racing formulations using synergistic chemistry combinations of base oils and additives. Engine oils, OEM or ‘off-the-shelf’, for service use are not satisfactory for ‘racing’ as designed to meet Government fuel economy and exhaust emission standards that impacts base oil viscosity, volatility and antiwear additives (e.g. zinc, phosphorus and sulphur based) plus be as lower cost as possible to keep the new car price down and competitive. Having said that, for transmissions, most consumers never even look at their ATF’s let alone change or prepare cocktail mixes so you are in a very special area. Good luck and hope you continue to find the right mix for you and your applications.
          Cheers
          Gary

23. I’m kind of confused. The picture says that synthetic oil lasts for 10,000-20,000 miles but most of the comments you reply to say to change the oil every 5,000 miles. Which should we go by?

    • Hi Jaden:
      Great question but no one answer for all as so depends on the OEM recommendations/warranty, age/condition of your vehicle, the way you drive, ambient weather conditions, engine load etc. plus the motor oil you select. If you have a relatively new vehicle that you drive normally quite regularly using the latest full synthetic motor oil that claims extended performance then 10,000 to 20,000 miles or 1 year oil changes is defiantely possible. Most late models have increased oil capacity/sumps and better oil filters so a lot more oil pumping around the engine than older vehicles. However if you drive under severe conditions such as very high temperatures, heavy load/towing, dusty or many short trips, then I believe you should change your oil at least twice a year or approx. 5,000 miles if less than OEM recommendations. For motorbikes I believe we should change the engine oil at OEM recommended miles or at least twice per year as a more severe environment.
      In addition, another key reason for OEM recommended oil change intervals either miles or time is for safety to check heaps of other stuff like tires, brakes, brake & transmission fluids, wipers, battery etc so that you meet their warranty requirements and be safe.
      Hope this helps explain why one answer may not fit all. Let me know what you drive/ride so I can maybe provide more specific suggestions for you.
      Cheers
      Gary

24. Hello, just purchased a 2016 RAM PowerWagon with the 6.4l engine. at 1200mls did the break in oil change (changed filter as well),and used what the manufacturer suggested (penzoil platinum). So I’m about to hit the service due mark. I used to autocross in my CRX (with zc Japanese engine) and beat the living crap out of it. Oh! did I mention it was my daily driver too? HA! anyway, used only Mobil1 5w-30 full synthetic in it and that engine was always immaculate. I do believe RAM recommends 0w-20 for the PowerWagon, Does Mobil1 have anything like that? Would you recommend switching (dumb question,but would like to hear your reasoning).

    • Hi Carlos:
      Got yourself a great motor vehicle as could look at RAM but to be honest I could not find much detailed info on the PowerWagon nor 6.4l engine on the web so let’s go by your details. Firstly, great to hear that you have first hand experience with Mobil 1 5W-30 keeping your autocross engine ‘immaculate’ – that is priceless re one of the major benefits of a ‘synthetic’ motor oil. If RAM recommends SAE 0W-20 Viscosity Grade for your PowerWagon, then confirm you could stay with Penzzoil Platinum 0W-20, now owned by Shell (Dutch) and use as advertised their “Pure Plus” Base Oil Technology (Group III) or maybe change to Mobil 1 0W-20 using their Exxon/Mobil Synthetic base oils! Switching brands at the first service oil change is not an issue as both oils are very high quality
      My assumption is that you may also ‘beat the living crap’ out of your new RAM, so suggest if you want to change brand then Mobil 1 0W-20 Advanced Fuel Economy for potential increased horsepower but motor oil & oil filter should be changed at minimum recommend intervals as stated in your RAM service manual. If not stated, then twice a year or every 5,000 miles. Key is to keep your engine like new!
      Cheers
      Gary

25. Curious as to what you’re thoughts are for the best protecting synthetic motor oil “off the shelf” selections. Got a 2000 GMC Sierra w/5.3L. Has 262,xxx miles on original motor,transmission,ect. Everything is stock and just want to keep it running great as long as possible. Also I don’t mind paying the premium price for synthetic motor oil as long as I know I’m getting a product with a quality BASESTOCK. Definitely do NOT want a high percentage group III hydrocracked basestock.
    Thank You, Tim

    • Hi Tim:
      You still have your GMC Sierra after 17 years and 262,00 miles and stock standard so tells me you look after your vehicle and wanna keep it for many more years! I do not know what motor oils you have been using nor your oil changes during this time, but let me assume you have been using good quality branded oils and changed oil & filter at recommended regular drain intervals? If so, and you are not having any high oil consumption issues, then I would suggest a top ‘synthetic’ oil from Mobil, Amsoil or Royal Purple that is SAE 5W-30 and formulated for high-mileage vehicles like yours. Unfortunately, no brand claims exactly what their base oil blend is so we can assume that when they state ‘synthetic’ it could be Group III (hydrocracked), Group IV (PAO) or Group V (eg ester) and a mixture of all or some unless they claim otherwise! So my guess is no matter what you choose, you are going to get a blend that is either designed to maximise performance (technical bias) or maximise profit (marketing bias). My guess, most are high percentage Group III to maximise profit unless clearly stated and guaranteed on the label! Good luck with finding that! Let me know if you do please 🙂 If you are experiencing maybe some increased oil consumption, suggest you could move upward in viscosity to a SAE 10W-40. High mileage motor oils are formulated with additional antiwear chemistry that is not allowed for a new vehicle as could adversely affect the exhaust emission technology such as catalysts – but for older vehicles past the warranty period, no issue. My suggestion is Mobil 1 High Mileage 5W-30. If you have not been using high quality branded ‘synthetic oils’ nor changing regularly including oil filter, then suggest you do a couple of 3,00 mile oil/filter ‘flushes’ of your new oil of choice to help remove any sludge/deposits that may be present. Hope this helps your decision.
      Cheers
      Gary

      • Good advice all overall, but I find averyone has their own story of why they like a particular product, so here’s mine. I was never going to use a synthetic engine oil, or other lubricant, because cars weren’t made for sythetics, only the “real” thing, mineral based. Well, how wrong a thinking that was, and is. My son introduced me to synthetic oil about 7 years ago and I have never looked back since. In fact, I am a staunch advocate for using synthetics in their proper place. As for engine oils, I use Amsoil now, but have tried several other brands to try and find the one that does what it says it will do. Synthetic blends are “OK” but, not much better than the conventional good brands, so they are off my list. Brand name is never a guarantee that the product you buy is going to so the trick, either. Valvoline, one of the best, has a list full of brand names that compete with each other for shelf space, yet some of their brands are not not necessarily top tier or even close. Mobil1 makes claims their products are the best and says they are the “number one selling” product in the world. True statement, but when you have the advertising budget they do, you can say a lot of things that are not necessarily true. The little guy, like Amsoil, has to work harder to make their pitch about their product being a better choice for the comsumer, because of their limited budget. Point is this, you, the consumer, has to mae the choice for yourself, not what someone else says, for you to be satisified. If saving money and keeping your investment in your car or truck is a primary priority, then do some testing of your own, or get input from more than just one person’s experiemce. I did all the testng myself over several years before I found the right product for me. Good luck and keep on truckin’.

        • Hi Albert:
          Really appreciate your personal experience and sharing. You are right on the ‘money’ re marketing versus actual performance – it is so difficult for consumers to choose because ‘synthetic’ doesn’t sound natural. Hence our website and your excellent comments. Amsoil as I understand buy & blend excellent synthetic motor oils whereas Mobil I know manufacture and blend excellent synthetic motor oils – a key difference in my mind. You are possibly right that marketing budget means that you hear/see more ’bout Mobil 1 but it also may come down to actual sales and profit! I have rated them, in my technical experience in the top 2 in the world – so we personally should feel good!
          Cheers
          Gary

26. Hi Gary,
    I just bought a 2017 WRX and I’m looking to change the oil for the first time. A friend recommended Motul group v oil. I was curious if the ester base would damage/deteriorate any of the seals,gaskets or plastics in the engine or associated parts? The reason I ask is I’m an aircraft mechanic by trade and a lot of airplanes use a phosphate ester base hydraulic fluid (skydrol). I’ve seen that stuff chew up paint, plastic, composite, etc. So, when I saw ester and motor oil in the same sentence I became a little wary. Any assistance/knowledge you could share would be greatly appreciated.

    • Hi Paul:
      Excellent question as esters are very polar and can “damage/deteriorate” seals/gaskets/plastics! I am very well aware of Skydrol as used to manage a laboratory that analysed in-use samples for condition –> that aviation synthetic hydraulic oil is based on phosphate ester technology as quite specific to hydraulic rather than engine oils! However, other ester chemistries are used in engine oils for cars and bikes. They also can swell seals but to counter act the “drying” of PAO etc for “fully synthetic oil” technology containing Group IV & V synthetic oils, a synergistic balance is required depending on the seals etc used in the engine/s. That is why the automotive and the oil industry have specifications that include seal testing to ensure the oils are fully compatible with their engines. So please refer to your Subaru WRX engine oil recommendation looking for API (American), ILSAC (International), JASO (Japan) and/or ACEA (European) plus SAE recommendation for your ambient driving temperatures. I tried on internet and got API SN & SAE 5W-30 only for a WRX – not very detailed. However, I would go with the best and in my opinion a “full synthetic” motor oil from Motul – say their HiTech 100 Plus 5W-30 – would please your friend although my base-oil guess is some Group V ester (<20%) and rest Group IV, III, II maybe? Otherwise, can suggest Mobil I Extended Performance 5W-30 with API SN,SL:ILSAC GF-5:ACEA A1/B1 and 15,000 mile protection and with probably similar base oil balance.
      Cheers
      Gary

27. 1/11/17 Howdy, what are your opinions on doing fully synthetic transmission oil changes in Hondas from the 2000 years? Our ’04 Civic LX has the owners manual stating to “only” use Honda fluids for changing everything from engine to steering to brakes, etc. Is regular brake fluid and power steering fluid conventional oil based? If yes, do USA companies make “those” in a fully synthetic with similar advantages for engine oil synthetics? Thank you!

    • Hi Edvard:
      Let me comment on your first question first – yes, I suggest you only should use Honda Genuine Fluids for transmissions, steering fluids and brake fluids unless you can find oil specifications in their service manuals! I couldn’t find any to suggest alternates! This is one way OEM’s (car makers) can lock you into their genuine products. They buy from oil/chemical companies anyway but with cooperative Research & Development have specific requirements which commodity oils do not meet – and during warranty period, could be an issue! Particularly brake fluids, they are very special fully synthetic oils based on glycol ethers or silicones specifically designed from a small number of chemical companies and totally different chemistry from synthetic motor oils. Do not mess with your brake fluid. Ya gotta stick with the brands and brake fluids should be changed every 2 years minimum they suggest as they do absorb moisture but transmission//steering oils can last >100,000 miles maybe! However, for your engine oil, check your service guide and I am sure your can find specifications that will allow you to use an oil other than Honda genuine./ For a full synthetic, I suggest Mobil 1 Extended Performance 5W-20, Oil Filter M1-110 and Mobil 1 Automatic Transmission Fluid meeting Honda’s specifications.

      Your Honda is >12 years old, wish you happy & safe driving forever!

      Cheers
      Gary

28. You mentioned that Mobil 1 was 40$ a quart on average. Is that correct or did I not read that correctly?

    • Hi Harry:
      We did mention actual cost but that was several years ago when we first developed the site. This is incorrect so apologise. We will delete as prices today are around $8/quart on discount bulk buys!
      Cheers
      Gary

    • 2007 1,100cc Vulcan with 57,000 miles. (Incidentally, the miles are from hot Alabama and Southern States riding) Ardent Mobil 1 user; the drain plug contains little to no shavings each time I change oil (around the 8,000 mile mark). My scooter continues to have great acceleration and runs cooler. Discussed and compared with other motorcycle owners (500cc to 1700cc) and those that use Mobil 1, swear by it as well.

      • Hi Smokey:
        That’s excellent news and field validation of a great product. I have also been using Mobil 1 since it was developed in 1974 in all my vehicles, motorbikes and even my lawn mowers – never had a problem with excellent wear control and cleanliness!
        Cheers
        Gary

29. Hey, i have a 1998 Plymouth Breeze using Pennzoil Platinum High Milleage in my car which i drive my car a lot, it has about 90,000 miles on the engine i have been using Pennzoil platinum high mileage in my engine since 70,000 miles. I am looking for the best cleanest most efficient engine i can ever buy for the buck no matter the cost. I have always sworn by synthetics since i torn apart a 2 stroke motorcycle engine with motul engine oil. The cylinder was shiny like a mirror no deposits i was amazed. Should i switch to Mobil 1 Synthetic High Milleage being that the group stock is V. I have used Mobil 1 in my moped which has 40,000 miles still running.

    • Hi David:
      Wow – someone still driving an 18yo motor vehicle regularly and wanting to continue to look after it – I’m impressed 🙂 As you have been using Pennzoil Platinum High Mileage for the last 20,000 miles and assume at regular oil-changes (5,000 miles max?) then your engine would be free of any sludge deposits from the first 70,000 miles 🙂 Can I also assume that you are not experiencing any significant higher oil-consumption so that your oil-seals and engine wear is also OK? If that is your experience, then you can stay with Pennzoil but I understand that oil is conventional, so a move to Mobil 1 High Mileage with synthetic base would maintain the benefits but also improve the cleanliness of using a synthetic. Also, if you do not have an oil-consumption, suggest stay with SAE 10W-30 which is the original recommendation from Plymouth. If you are using a bit more oil than normal, you could move up in viscosity to SAE 10W-40 – but just be very careful of very cold conditions. Suggest check your manual re SAE versus ambient temperatures where you live/drive as at 5,000 miles/year for you in your Plymouth the oil needs to protect your engine over all 4 seasons. Happy Driving.
      Cheers
      Gary

30. Gary,

    I ride a Kawasaki KLR650. In reading the KLR forums everyone swears by Rotella T diesel oil easily (and cheaply) found at Walmart. I find it hard to believe that the cheapest (non motorcycle) oil on the market could be the best. But I can’t find one negative comment on the forums about it and everyone raves about it. Is this just a case of the blind leading the blind or is there good reason to believe this is the perfect oil for a KLR (with frequent changes). I am aware of the need for oil in wet clutches of motorcycles but no one seems to think it’s a problem with this bike.

    • Hi Andy:
      My first assumption is that your Kawasaki KLR650 is a 4-stroke, DOHC, single cylinder, water-cooled and gasoline fuelled bike – not the military diesel fuelled engine! The year of make doesn’t matter as lubrication I understand would be the same for all models. The absolute key to correct lubrication of your engine, wet-clutch and transmission as shared design (one oil for all) is the industry specifications recommended by Kawasaki themselves being for viscosity SAE 10W-40 and performance JASO MA (Japanese Automotive Standards Organisation). The key re JASO MA is that with a wet-clutch some gasoline engine oils contain friction-modifier additives that really help improve fuel consumption in engine parts such as piston rings, valve trains etc but could have very detrimental performance/slippage in the wet-clutch of a motorbike! Shell Rotella T Diesel Oil (is it SAE 15W-40?) you refer I understand does meet JASO MA – so maybe contains no friction-modifier additive/s – so works well with regular oil changes – but is it the best? My suggestion regardless of price is a ‘synthetic’ based SAE 10W-40 with JASO MA –> so suggest maybe try their genuine brand Kawasaki 10W40 Synthetic Oil or Mobil 1 Racing 4T 10W40 to maybe maximise protection in all aspects!
      Cheers
      Gary

      • Thanks for the quick reply Gary. Yes the KLR is a 4-stroke DOHC, single cylinder, gas, water cooled, and yes it’s the 15W-40. It is labeled as meeting JASO MA and that seems to be what a lot of the talk on the discussion boards point to as being key. There is also discussion about making sure not to use an oil with friction-modifier additives just like you said, and the consensus on the discussion boards is that Rotella doesn’t have any. How would one know about that if the additives are propitiatory? So my takeaway from you is that while there are surely better oils out there, there is no reason to think this would do any harm to the engine, transmission, or clutch with regular changes? Even so, I’m pretty sure I’m going to switch to a motorcycle specific oil. There was one comment on a discussion board that rang a cord with me: “call me crazy but I use a car oil in a car; diesel oil in a diesel; and motorcycle oil in a motorcycle”.

        • Hi Andy:
          Thanks. If the oil claims JASO MA then it has already passed the wet-clutch performance requirement so need to worry ’bout it containing detrimental friction modifiers.
          Happy & safe riding!
          Cheers
          Gary

31. I also live in south louisiana a hot environment in summer, would mobil 1 20w50 motorcycle oil be better than a 10w40 compared to indians recommended 20w40 semi. syn. oil?

    • Hi Randy:
      Please see my first response to your first question – I agree with you – SAE 20W-50 in those hot Louisiana environments is the way to go to protect your Indian engine! Try and get Mobil 1 V-Twin 20W50.

      Also suggest you change your engine oil and filter as per Indian service guidelines taking into consideration how you ride that beaut bike! 🙂
      Cheers
      Gary

32. I have a 2016 indian chieftain motorcycle, indian recommends 20w40 semi. syn. indian oil. I would rather use mobil 1 10w40 full syn. motorcycle oil, that should be okay for the engine? Your thoughts please, thanks.

    • Hi Randy:
      Wow, latest Indian Chieftain is your new ride – congratulations. The bike looks absolutely awesome – huge & mean – an air-cooled 111ci V-Twin! An icon and looks great! I checked the site for Indian Oil 20W-40 Semi-Synthetic to try and answer your question but was really disappointed in the performance data. There was nothing about base oils used nor API industry specifications 🙁 I find this very frustrating for many ‘genuine oils’ but it is part of marketing – so cannot technically compare. However, that leaves me open to suggest the best engine oil for your 2016 Indian is Mobil 1 V-Twin 20W-50 as loves high temperatures but more importantly has API CF as well as API SJ & SH industry performance!
      Ride Safe 🙂
      Cheers
      Gary

33. Hi,
    I was wondering if it would be better to run Mobil 1 synthetic 5w30 or 10w30 in my 2005 Volvo s60R. I have a bigger turbo setup and a stage 4 tune. Volvo engines run hot in the first place, plus on top of that, I have a bigger turbo, full exhaust, down pipe, etc. added roughly 100whp. Which oil will lubricate and cool down the turbo the best. It is a comp triple ceramic ball bearing turbo that is only being cooled by the oil that’s going through it. I live in CT and it is only drivin in the warm months. Stored for winter. I want to know if the 5w30 is too thin and not sufficiently lubricating the turbo and cooling it down. I’d really like to know what you think. Thanks!

    • Hi Jay:
      An oil-cooled turbo is a real challenge for every motor oil rather than a water-cooled turbo as the temperature difference is huge! Also sounds like you have ‘juiced up’ that engine a ‘little’ bit from factory specs so hotter again! Firstly, suggest you stay/move with/to Mobil 1 Extended Performance 5W-30 as both viscosity grades you mention will protect the same at the high temperatures but with an oil-cooled turbo suggest also that you change the oil as per Volvo states in their service booklet or every 5,000 miles. Reason is that the best synthetic motor oils can handle extreme turbo temperatures better than conventional motor oils but the major problem with oil-cooled turbos is that when you shut down the engine, the oil stops flowing and sits in the turbo and literally ‘cooks’. I’ve seen some very nasty blown turbos with all oil channels blocked with ‘cooked & coked’oil! Question for you, when you finish driving for the day, do you keep the engine running for a few minutes to keep the oil flowing thru the turbocharger to help with cooling – that would be good! I have also read about ‘Engine Oil Cooler Upgrades’ for Volvo s60R’s, so maybe research that?
      Good luck & good driving in the Summer!
      Cheers Gary

34. Best Mobil One synthetic oil product for 2009 GMC Sierra Denali crew cab truck with 106000 mostly “unloaded” miles? Truck has 6.2 engine and history of 5W30 Valvoline synthetic oil changes at quick oil change business.
    Thanks
    Robert

    • Hi Robert:
      For your ‘lightly loaded’ GMS Sierra 6.2l V8 that has obviously been luved and looked after with regular oil changes the Mobil 1 for you needs to be an SAE 5W-30, meeting GM6094M or Dexos 1 performance –> you could change to Mobil 1 Extended Performance 5W-30 and extend oil changes to 15,000 miles or to Mobil 1 5W-30 meeting above performance with normal oil changes.
      Cheers Gary

35. hi gary,nice that your helping us about what you know in oils so here’s my question to you..what is best motorcycle oil for my gixxer 150cc that is fully synthetic..my bike is almost 2 months and my mileage is around 4000..thanks and more power..

    • i forgot to say that my recommended oil in manual is 10w-40,so what is best for me?..what can you say about shell 4T ultra 10w 40 synthetic and mobil 1 racing 4T?..

      • Hi Coping:
        For your ‘brand new’ Suzuki Gixxer 150cc 4-stroke motorbike, Shell Ultra 4T or Mobil 1 Racing 4T 10W-40 engine oils will meet your needs as I reckon you will be changing the oil at or before recommended intervals! 🙂 Just based on viscosity, you will not probably get any more power from different brands of 10W-40 brands? I suggest riding expertise and practice could make you go faster – on a race track of course!
        Cheers & happy riding
        Gary

36. Correct me if I am wrong, but I believe that Mobil 1 Extended Performance is the only Mobil 1 oil that is Group IV based.

    • Hi Sean:
      Not sure of your resource/s – but suggest please check. I believe you are wrong – as far as I understand all the Mobil 1 Family still contain Group IV PAO!
      Cheers
      Gary

37. Great article Gary.

    Easy to read and steps through information nicely. You may have missed one piece of critical information however. Mobil 1 has been a Group III synthetic for a good number of years now (after a US judge ruled that a hydrocracked Grp III could be called synthetic).

    I used Mobil 1 for many years but walked away when they downgraded to a hydrocracked mineral oil.

    • Hi Tim:

      Firstly, many thanks for your positive feedback 🙂 I didn’t miss it, I was directly involved at the time. Yep, Mobil lost that one way back some 20 years ago in the USofA by a non-technical/non-scientific judge. As a techo/scientist I was so disappointed that the judge didn’t understand the science and still am but for marketers opened up new claims promotion re ‘synthetics’ & ‘semisynthetics’ for many other lower performance products the ‘synthetic’ claims flourished – and also the marketing price. But let me reassure you that Mobil 1 did not change to Group III then as there are so many technical reasons it could not –> viscosity, low temperature, volatility, extended performance, purity etc etc. But lots of conventional products started to claim ‘semi’ or ‘synthetic’ by the marketers and confused the consumer! Today, we should all read the claims made but I’ve provided some choices that I believe are the best ‘synthetic’ engine oils in the world.

      Cheers
      Gary

38. Which synthetic motor oil do you recommend for 2015 Ram Cummings turbo diesel?

    • Hi John:

      I would like to help but I do need some more details –> Model & Engine?

      Cheers
      Gary

39. I have read numerous articles about engine oil but in regard to listing which brand is best I think is fertile. Blackstone have done many analysis of oil samples and conclude that there is no difference in the major brands products. One isn’t significantly better than another despite the marketing hyp.

    • Hi Bazza:

      I understand that Blackstone is a laboratory that tests used oil which is a combination of oil & engine condition during service –> cost approx US$10 per sample –> so many variables! But synthetic oils by my experience last longer and protect longer!

      For API qualification a new engine oil has to undergo maybe >US$1 Million of standard industry engine tests – this is the real arena as it includes actual detailed engine wear & deposits as well as oil condition!

      Cheers
      Gary

40. Gary,sorry to say but it seems that you are totally Mobil 1 biased.Seems to me when comparing oils Amsoil comes out on top a good majority of the time.Guys with a little savvy know Mobil 1 sold out years ago .Not sure why Mobil 1 is even on your list,the intro says only PAO will be considered in your top 5.Even Castrol shouldn’t be there unless it’s the German version, nor Pennzoil for that matter.What gives?That Mobil 1 factory fill story doesn’t work either,we know somebody is paying for that endorsement,probably Mobil pays with $ or free oil to the car manufacturer to get it.Thank you for your time.

    • Hi Jim:
      Yes, you are right, I might be Mobil 1 biased, but my comments are based on objective information and almost 40 years of experience. Please note Amsoil I discuss as #2 but still a marketing company that buys technology, similar to Castrol. Must admit, I am getting a bit long in the tooth so maybe outta touch in the last few years. However your subjective comments re “sold out” and “factory fill” I welcome as your personal opinion, but will remain just that…unless you wanna challenge Mobil? Good luck!
      Cheers
      Gary

      • AMSOIL challenges Exxon/Mobil all the time. AMSOIL’s best is a 25,000 mile motor oil. Mobil 1’s best is 15,000 miles. AMSOIL vs Mobil 1 5w-30 http://wpc.1c96.edgecastcdn.net/001C96/G-Items/Performance%20Testing%20Archives/g3115-2013-current/index.html . AMSOIL VS Mobil Diesel oil http://wpc.1c96.edgecastcdn.net/001C96/G-Items/Performance%20Testing%20Archives/nordicwastestudy-2010-archived-05-28-2013/index.html and http://wpc.1c96.edgecastcdn.net/001C96/G-Items/Performance%20Testing%20Archives/nordicwastestudy-2010-archived-05-28-2013/index.html . Gear Lubes http://wpc.1c96.edgecastcdn.net/001C96/G-Items/Performance%20Testing%20Archives/g2457-2007-archived/index.html . Motorcycle oils http://wpc.1c96.edgecastcdn.net/001C96/G-Items/Performance%20Testing%20Archives/g2156-2009-archived/index.html. Never seen Mobil 1 outperform AMSOIL in over 40 years.

        • Hi Tim:
          Yep I agree that Amsoil is a great synthetic engine oil blender & marketer and in my top 5 as a product. So stay with their products if you are happy and convinced. However, I read your first link to a ‘challenge’ by Amsoil re ‘AMSOIL vs Mobil 1 5W-30’ against API SN/ILSAC GF-5 requirements. This is what I saw –> Amsoil only selected 5 Laboratory Bench Tests for the ‘comparison’ out of dozens of both Laboratory & Engine Tests! On the very first Laboratory Bench Test they report, the ‘Four-Ball Wear Test’, Amsoil stated “Although not widely used as an engine oil test…” so lets immediately scientifically reject that comparison/test as I did & didn’t read any other links. But I read a bit more on your first link and found that Amsoil, for some reason, did not compare any other Laboratory Bench Tests results including Foam, EOFT, EOWTT, Aged Oil, Emulsion, Homogeneity, Gelation, Ball Rust & Elastomer Compatibility. But what about the actual most important Engine Tests comparisons that would include Sequence VID, Sequence IIIG, Sequence IVA, Sequence VID, and Sequence VG measuring actual engine wear, varnish & deposits on pistons, rings, cams, valves etc etc –” nothing?. During engine oil development, total Laboratory Bench Tests cost hundreds of thousands of dollars, Engine Tests cost millions of dollars. A true scientific comparison not gunna happen as results can bounce around & change every other day. I think that Amsoil is a great marketer, has very good products but very selective in its technical challenges. Just a reminder, I have only referred to Amsoil so would be interested in their data for all their competitive products – not just Mobil 1!

          • I guess you didn’t read the other links I provided. You would have seen the other tests you mentioned and many other brands. Many more tests at http://www.amsoil.com/performancetests.aspx/

41. Hi Gary,
    Three questions to be sure I’m on solid ground.
    1. I read an article a few years ago by a race car owner/driver on the benefits of using 0W synthetic oils due to better cold start lubrication. Made sense so I started using Mobil 1 0W-30 in my 1995 Jeep Cherokee, rather than 10W-30 as specified in the manual. No issues. Runs great at 177,000 miles. Am I overlooking anything in switching to 0W?
    2. My 2016 Mazda 6 recommends 0W-20, however 20 weight just “seems” too low for best high speed/high temp operation, so I’m using 0W-30 in it just as I did in my 2011 Mazda 6 and in my supercharged 2002 Miata. Again…am I overlooking anything by using 30 weight vs. 20?
    3. Is switching to 0W-40 a good idea in either the Jeep or Mazda 6?

    I drive in Arizona at 5000 ft elevation. Winter down to 10 degrees. Summer up to 100 degrees.
    Thanks!
    Jim

    • Hi Jim:
      Sorry to be a bit slow to respond but been away for the festive season – btw – Happy New Year! You’ve asked some great questions and are on the right track! I would luv to visit Arizona one day! The ‘ambient’ temperatures you refer to I assume are official from weather stations where they are measured in the shade and outta the wind with no heat soak nor wind chill taken into account so in real terms for your engine/oil temperature could be much lower in winter and much higher in summer. Wow, you live in an extreme range of temperatures over the year. The SAE Viscosity Grading system is now designed to help with a lot of performance criteria such as cold starting in winter conditions, fuel economy, engine wear & protection, oil consumption, horsepower etc.
      1. So in quick terms, the lower the xW, the faster cranking speed to start your engine so 0W would be great in winter at your temperatures near/below 10F.
      2. If you want to ensure ‘better’ wear protection at consistent higher speed/temperatures and sacrifice very ‘little’ in fuel consumption then 30 is better than 20. Don’t forget, the biggest contributors to ‘higher’ fuel consumption are your driving style, under pressure tires, vehicles full of ‘junk in the trunk’ etc
      3. Based on above, let me fully support you, and if you change your engine oil once a year for both the Jeep and the Mazda, stay with Mobil 1 0W-30.
      Cheers
      Gary

42. Hi I have run mobil synthetics now for 25 years over millions of hours in marine.we have achieved a standard running with Mobil Delvac 1 —3000 hours in main engines and up 5000 in 1500 rpm generating sets.we dis add on bypass oil filters as well but as we oil sample each 250 hours we know without doubt it is a better success story than running mineral oi.We use synthetic transmission oil and greases as well.A recent test on a Cat dyno running full 1 hour tests using high quality mineral oil as compared to Mobil Delvac 1 gave 1.14 litres per hour fuel consumption savings with Delvac 1 , this was with a small Cat 3208 engine that had been overhauled.The larger the engine the better the fuel savings get from past dyno tests.This gives us huge operational savings both with the lubricant and with better diesel fuel consumption.Hopefully this information is of assistance , regards Terry( Perth, Western Australia)

    • Hi Terry: Great to see you are still having success with full synthetic oils & greases. I very well remember working with you in the early days as you pioneered use of synthetic engine oils in marine applications with Mobil’s Delvac 1. I did meet with you in Perth on a few occasions to talk technical and then catching up when you visited the east coast at the Formula 1 Grand Prix & Bathurst 1000 Races on more social occasions. Hope you are still using Mobil 1 in your HSV/s? Cheers 🙂

43. Best synthetic oil for a 2007 jeep patriot?
    Ive been taking it to jeep dealership . Im guessing they been putting in mopar synthetic oil & recently heard their service dept has been lacking in customer service.
    Tourn on who to trust now :/

    • Hi Crystal: I need to make two suggestions depending on the mileage & condition of your engine. If you have had regular oil change services using a high quality oil, with no oil leaks, nor high oil consumption and your engine appears relatively sludge free (clean), then suggest Mobil 1 Extended Performance 5W-20 which you can extend your oil change to 15,000 miles. If however your engine may be sludged up a bit, not certain of the previous oil quality and the engine has done more than 75,000 miles, then change suggestion to Mobil 1 High Mileage 5W-20. This oil will start to clean your engine up so you need to change oil at 5,000 miles. If you find an increase in oil consumption during clean up, try a Mobil 1 of higher viscosity. Hopefully you have looked after your engine with regular servicing using a high quality oil and wish you many more years of happy motoring in your Jeep 🙂

44. I have a 2010 VW Golf TDI (with a particulate filter) which requires the 507.00 spec synthetic oil. I live in Canada and I’m contemplating the Mobil 1 ESP Formula 5W-30 or the Casterol Edge SPT 5W30. Which oil would better suit my desire for better fuel economy? Does it matter what fuel filter I choose? Thanks.

    • Hi Pete: Let’s clarify the filter question first – if you are talking about the diesel fuel filter, then this has nothing to do with the engine oil so use VW approved fuel filters. If you mean diesel exhaust gas particulate filters, then this is what the engine oil specification VW 507.00 is all about. To get VW 507.00 approval the engine oil must be formulated with low sulphated ash, zinc & phosphorus as these can ‘poison’ and deactivate an exhaust gas particulate filter. If you want to change your exhaust gas particulate filter then also use VW approved filters. When it comes to fuel economy, the most important factors are how you drive, how loaded up your vehicle is, tyre pressures etc. Both the Mobil 1 & Castrol products you mention are SAE 5W-30 viscosity so should provide basically the same fuel economy. I suggest Mobil 1 ESP 5W-30 as it is approved against VW 507.00 Good to see diesel fuel being used in Canada – but to look after your VW Golf, minimise fuel economy & emissions try and always use manufacture approved parts, the best diesel fuel, and of course the best engine oil. Regular servicing is the key. I would love to revisit Canada one day 🙂

      • Thanks for the suggestions. I meant the oil filter. I was wondering if there is a difference between oil filters. I’ll take your suggestions to use manufacturer approved parts and stick with VW OEM filters (usually Mann).

        • Hi Pete: Sorry for late response – yes, suggest use VW approved oil filter for your imported model.

45. I would like to have your input on an application that is a little different than the engine combustion world. I have a high pressure natural gas compressor that seems to be having a problem with the oil traditionally used (Esso 122 synthetic).Since there is no combustion in the chamber all the carbonizes is the valves and that only happens at higher temperatures….so essentially the oil change ends up to be slightly darker than when it went in….and it contains ring material (F12) and some carbons. I am looking for a synthetic oil to handle heat issues that does not have detergents or the like to try and combat a combustion engine. Any help would be appreciated

    • Hi Jim: You have an industrial application looking for a synthetic compressor lubricant for natural gas. You are right, you should not use a high detergent engine oil. I do not know where you live, but if you check the Mobil web site under Synthetic Industrial Lubricants I am sure you will find a suitable synthetic natural gas compressor oil recommended, or at least a contact telephone number or email address to talk to an expert. Good luck 🙂

46. Torn over hendrick motor sports synthetic oil change.im huge gordon fan been using quakerstate since there intial change to it. Now theyve changed back to valvoline thinking of making the change what are your thoughts. 2014 ford fiesta st. 21,000 miles

    • Hi Calvert: Just luv watching & following racing myself. FYI, Racing Teams do change sponsorships for many reasons, but sometimes their engineers don’t change the oil they use until they have done some serious testing! But, to your specific question, your car a 2014 Ford Fiesta with only 21,000 miles is as good as new as long as you had regular oil & filter changes as per your driving habits and manufacturers guide. If so, and you are not having any oil consumption, you can change to Mobil 1 Extended Performance 5W-20 which meets your cars requirements for Ford WSS-M2C945-A oil quality I understand is required for your Fiesta. Will provide maximum protection, up to 15,000 miles oil drain period, & best fuel economy. Also strongly suggest a new oil filter to ensure you have 100% of the new oil & no used oil residual – for extended performance believe Mobil’s M1-102 oil filter is the one for your Fiesta. Good to double check with the Mobil 1 website. Happy motoring Calvert with a car you can keep for many years more 🙂

47. I have a 2014 gmc Sierra 5.3 what is the best oil to use in it.

    • Hi George: Your 2014 GMC Sierra 5.3 is a beaut looking Pick-Up! And, my guess that exhaust sound from the 5.3L V8 is music to your ears. I have a Chevy 6.0L V8, and just luv the exhaust note when accelerating so smoothly away from the traffic. However, with the environmental laws we have nowadays, the note is quite subdued 🙁 I suggest for your Chevy 5.3L V8 engine, Mobil 1 Extended Performance 0W-20 which should provide up to 15,000 miles oil-drain period, improved horsepower or reduced fuel economy depending on how drive your Sierra. Also, strongly suggest you change your oil filter at the same time to ensure you don’t dilute your Mobil 1 with any residual used oil. Plus to ensure you get that extended oil drain comfortably, I think Mobil’s M1-212 oil filter is the one. But suggest you check your service manual and the Mobil 1 website. Wish you wonderful smooth V8 cruising in your Sierra 🙂