Sorry guys and thanks for the good advice. I've been away a bit. It's a Peugeot 308 1,6 HDI. FF layout. The following years they changed it to a 75W-85 GL4+...whatever that + means. Mola was right...these guys were probably playing it safe in the beginning...that would explain the gl-5. However lot's of manufacturers ask for GF-5 in Europe...could it be for the same reason they ask for thicker engine oil grades? My guess is GL-5 would be a better protection in severe (European) conditions where synchro durability would come second. Another thing would be the early torque of these Diesel passenger cars. I mean you get Honda S2000 numbers at 1800rpm instead of 6800rpm (and 60mpg as a bonus).
And it DOES have a hypoid final drive gear set...for packaging and weight reasons probably. But I would"ve guessed this is not a sufficient reason by itself... I always though GL-5 would be appropriate when changing by 90 degrees the rotational thing like in a FR layout combined with a hypoid set.
I wish I knew what the + means. I've seen Redline using it as well but in a gl5+ or gl6+ manner.
Originally Posted By: MolaKule
Quote:
Most of them out there are GL-4's or GL-5's having friction modifiers for LSD.
I think you have been misinformed.
MTL specific fluids DO NOT have LSD friction modifiers in them.
What vehicle is this; you never told us?
Unless the transaxle has a hypoid design, you don't need a GL5. Most modern transaxles have spider gear differentials and a GL4 will offer sufficient protection.
It sounds like another rediculous spec from the OEM due to lubrication ignorance.
