G. Comments about Mobil 1, and extended life Mobil 1
It is interesting that the new Mobil 1 "extended service" oils added more ZDP to the
oil to prevent depletion of the anti-wear additive to market the extended drain intervals to 15,000. BUT....read the bottle. It specifically states that if your engine is under warranty, change the
oil at the specified intervals...hmmm....so much for their "guaranteed 15,000 mile interval. Another gem on the bottle is the statement that "if your engine has an
oil life monitor follow the oil life monitor and do not use the extended drain interval." The bottle also says that the extended service is void if the engine operates in heavy duty/commercial/livery service, is idled a lot or is operated in a dusty environment. That pretty much eliminates a LOT of other applications and matches the manufacturer's recommendations for sooner oil changes under those conditions. So..after reading the can, exactly what good is the "extended service" Mobil 1. In addition, if you look carefully, the extended service Mobil 1 does not have the API SG3/SG4 rating as it exceeds the anti-wear (
zinc) concentration for the API SG3/SG4 ratings. This is not necessarily bad for motorcycles but makes the oil a NON-recommended oil for most modern passenger car applications. I am not making this up....read the fine print on the bottle yourself. I would change the oil at the normal intervals even if you do use a
synthetic oil.
It isn't MY conclusion...it is a fact. Mobil even says the same thing. They have not stated anything about extended drain intervals with their products until the recent addition of the "extended service -15000"
synthetic oil. And they had to modify their existing Mobil 1 product to make that claim (modified to the extent that it doesn't conform to the SG3/SG4 specs anymore) and they STILL put tons of qualifiers on the 15000 claim with the disclaimer about changing it according to the manufacturer's oil life monitor, and changing it sooner if under warranty or operating in towing/commercial service or dusty environments. I am not making that up....read the bottle for yourself. With all the other reasons for changing the oil there is no way that
synthetic can claim a longer drain interval.
The fact is that the "extended service" claim for the Mobil 1 15000 oil is a bit hollow...especially when they add several $$$ per quart for the 15000 oil. A modern Cadillac Northstar or LS1 engine will go 12500 miles on the oil life monitor if used in highway driving, best case conditions...and that is validated with conventional, non-synthetic oil !!! So for the extra $$$ for synthetic and extra $$$ for 15000 you only get 2500 extra miles...and Mobil tells you on the bottle NOT to go 15000 if your car has an oil life monitor. If you saw data showing the oil was fine with extended drain intervals then conventional oil would have done the same thing on that particular test.
H. Comments about
Amsoil
Forget the idea that synthetic allows longer drain intervals. It is hype by some of the synthetic marketers (primarily
Amsoil) to sell/justify their expensive (highly profitable) product. They test under one set of best case conditions and then imply that that is the case for all conditions. Any oil claims of extended drain intervals that do not make the distinction of what type of service or what type of engine should be highly suspect and considered primarily a marketing ploy. Period.
Amsoil.....????.....That is an oil marketing company that utilizes a pyramid scheme to sell their product thru a system of distributors and dealers and such. They know absolutely nothing more about oil than Mobil or Texaco or the other major oil manufacturers. Their bogus claims are meant to sell their products at high prices to benefit their pyramid marketing scheme. How could they justify the high price they charge for their product otherwise. Their products probably perform well to some extent but they have no outstanding attributes that others do not have for half the cost. Their claims of long change intervals are completely nonsense. They base them on the lower oxidation rates of their synthetic products at high operating temps. As mentioned, that is rarely, if ever, the defining factor in oil changes and the testing that determines the oxidation rates is run at temps above what most engines will ever operate at. They take something completely out of context and pretend that it is a big advantage. It isn't.
If you look at all the tests that oils must pass to meet the API standards for performance, Amsoil only quotes selected results in areas of testing that do not replicate normal engine operation. If you really understand ALL the things that govern oil life Amsoil's claims evaporate. They make themselves sound very technical and quote lots of "data" but it is a smokescreen to cover their marketing scheme that benefits their distributors and dealers.....
donaldd34 mentioned:jestal - I read your prior replies basically stating not to extend oil changes past 12K miles or so and also the hype you said put out by Amsoil. But what about people who have run 25K miles on synthetic oil, have it tested and its still good for continued use. The TBN is still OK (like 4 or 5), the wear metals are not high and the antiwear additives are OK. I assume you can tell from the oil analysis whether the ZDP is depleted? If Amsoil products were pure hype, then why do their SDF filters score tops in the SAE H806 tests? Not trying to defend Amsoil, just trying to pry out a little more info.
I guess I would have to ask what is "OK" for anti-wear additives??? The anti-wear additives are positively going to deplete with engine revolutions whether you track this with revs, miles, hours, etc......they are going to deplete steadily. If an engine is not taking much anti-wear additives out of the oil (such as modern car engines with roller followers, no gears, etc...) then obviously the anti-wear additives will last longer....documented by the current allowance of 12,500 mile oil changes per the GM oil life monitor on many engines. So....how low do you want to go. Frankly, I tend to be relatively conservative and so does the GM oil life monitor. I consider the anti-wear additives to be below "safe" levels when it drops below 50% of concentration. So, theoretically the oil could go twice as far if ZDP depletion was the governing factor.....IF you were willing to run the oil down to very very low concentrations of ZDP.