>> > Mobil 1 5W20 also meets the Ford specification but may not actually be
>> > worth paying twice the price of the Motorcraft oil.
>>
>> Just a note. I heard on the TeeVee that EPA has removed most/all wear
>> additives from new oil classifications.
>
> The ones that poison catalytic converters have been removed.
> ZDDP was a cheap way to make mediocre base stocks perform to
> specifications. The elimination of ZDDP has forced the refiners to
> choose better base stocks and use more expensive additive packages. >
>> That makes Synthetic probably
>> the only way to go unless STP is still out there and I'm not too sure
>> that it has wear additives such as zinc.
>
> It's a good bet that any motor oil that meets the more stringent GM,
> Ford, Chrysler, BMW, VW/Audi, Saab etc approvals will be at minimum a
> synthetic blend even if it isn't labeled as such.
>
> If it's Zinc you want, I think Amsoil still uses it in their oils, which
> probably explains why most of their oils don't cary the critical OEM
> approvals one should follow to maintain their warranty.
> (also makes me think their oils aren't really as good as they claim)
Some AMSOIL products do meet API specifications. Please read this web page to discover the truth about AMSOIL's choice to produce oils with higher levels of ZDP. Pay particular attention to the NOACK volatility scale and it's effect on oil evaporation which causes vehicles filled with AMSOIL to have no more catalytic converter problems than regular oils with the lower levels of ZDP that meet the API specification.
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