ditchmyster

iTrader: (7)

Thanks maz, hope your getting better.

good thread.:-)

DIPSY

Run Castrol syntrax universal 75/90 in 6 speed .Did have it in the diff but changed to Fuchs titan 90ls .Diff is very very quiet now compared to the 75/90.It says in the Jap maintenance service schedule the bits that are in English for Lsd 90.Every body has there own opinion what oil they use

Maz

iTrader: (34)

Getting there mate. This oil selection malarkey can be a bit confusing. However Alyn can usually separate the wheat from the chaff as he not only supplies fluids but builds cars. 👍

supshon

iTrader: (5)

Changed my oil in gearbox and diff , no luck with fixing , has now had a new centre diff and rear diff bearings , drives lovely now , bit faster too due to less money in my wallet

fpan

iTrader: (11)

Correct, LS is for DCCD cars.

For non DCCD cars a "normal" (i.e. non-LS) oil should be used.

I use Motul Gear 300 75W-90 in mine (non-DCCD).

chopperman

So all the non DCCD cars don't have a rear limited slip diff ?

AS Performance

iTrader: (4)

no thats totally wrong i'm afraid, as per my previous post the DCCD is part of the gearbox and has NO relationship on the type of rear diff fitted.............

you can and do get cars that require LS oil for the rear diff that do NOT have DCCD

Inviroman

iTrader: (2)

So does my 2002 bug STi need to have LS oil in the rear?
Current got Millers CRX 75/90 in.

AS Performance

iTrader: (4)

thought this had already been covered............

simply YES..........

chopperman

As i suspected. Thanks for clarifying.

Inviroman

iTrader: (2)

While at the workshop today doing my engine oil change, checked on the autodata system and it states that only 75/90 synthetic oil should be used in the rear diff, also checked on the Millers and Mobil web sites and same so chose not to do the diff with the LS oil.

cster

I would not use an external site like Millers or Mobil to see what is an appropriate oil type for a specific model of Subaru. In my experience, they will give you the wrong information when it comes to STI rear diffs.
Use the owners manual that came with the car or take the advice of someone who knows about Subarus like AS Performance or API would be my advice.

chopperman

Its not that the 75/90 is the wrong oil, it's just there is a better alternative. The LS oil is just a gear oil but with more shock absorbers. This being more suitable due to the way the LSD's lock up. Well that's how i understand it. Your car has a limited slip diff, the LS oil is designed for that application. Simple as that.

Inviroman

iTrader: (2)

Put the LS oil in the rear diff today, will see if there is any difference, will post my findings.

hodgy0_2

Yes, make sure you can remove the "fill" plug, before you you drain the oil

I speak from bitter experience btw