> Did you know they also rate gear oils also? The API ratings for
>gear oil is
>
> GL 1
> GL 2
> GL 3
> GL 4
> GL 5
You have to actually read the specifications. GL-4 is NOT BETTER than GL-5.
They are for different applications. GL-5 is for differentials where max
gear pressure protection is required. GL-4 is specifically for synchomesh
transmissions. GL-3, I believe, is for non-synchomesh transmissions.
Same may be true for API motor oils. Some of the later standards are more
focused on "energy conservation" and reduced emissions, or catalytic
converter friendly additives, instead of say, resistance to corrosion and
high pressure protection.
Regards,
Rob
_________________________________________________________________
|