Final Drive gear oil query

Post by **mib** » 15 Sep 2008, 17:27

Hi,

I'm planning to treat my auto T25 final drive with some fresh and new oil.

I've got already got some EP80 API GL4 gear oil but the haynes manual states that I should use EP90 API GL5!!

Is there much difference between the 2 grades?

Am I ok to use the EP80 oil or should I buy EP90 oil?

What should I do?

Post by **Fritz** » 15 Sep 2008, 22:13

Are you sure you have the correct oil for an Auto box ? I could have sworn any T25 Auto box model uses ATF rather than EP80-90 .

EP 80-90 is recomended for 4 + 5 speed manual gearboxes ....

Regards

Fritz,,,,,,,,,,

Post by **mib** » 15 Sep 2008, 22:49

Defo ATF for the Autobox but EP90 gear oil (according to Haynes manual) for the final drive.

Post by **Syncro G** » 16 Sep 2008, 00:57

Autoboxes use ATF in the gearbox but have seperate oil for the final drive (unlike manuals), its very often overlooked (good to know the haynes book of lies hasn't missed this one)! Doubtless VW would also claim it never needs changeing, but it does.

ep80w90 is the most common grade avalable and is suitable if ep90 is speced.

As for GL4 Vs GL5, its usally yellow metals that have a problem with GL5 so things like the synchro cones and shims in some manual boxes (inc T3) mean you can't use it. As its just a diff I wouldn't have thought it'd have those matereals so eather grade would be fine. If it says GL5, GL4 should also be fine but not the other way round.

Post by **T-3PO** » 16 Sep 2008, 06:38

... bottom of this thread https://club8090.co.uk/forum/viewtopic.p ... hlight=oil is a chart for VAG approved oils ... it's a bit blurry but you can just about work it out!

Post by **mib** » 16 Sep 2008, 17:21

Thanks guys.