Recommended oil for torsen LSD

Thu Mar 10, 2016 9:55 am

Hi Zoner's,

Recently bought a second hand medium case torsen diff. I will be fitting this to the car this weekend hopefully.

Just wanted to check what oil I should be putting in this? Google has been fairly useful but cannot pin down which one exactly for the torsen? From what I have worked out I need a 75w 90-140 and anywhere in between?

It would also be useful to know how much a medium case holds and if anyone knows a source for replacement plugs and gaskets?

Many thanks.

Thu Mar 10, 2016 1:01 pm

The torsen diffs just use normal EP90 it is the plate type LSD that needs the 75w 90-140 due to the friction plates.

The torsen diff uses the helical gear to do the torque biasing action so no special friction modifiers are needed.

I think that may have been one of the reasons BMW started using them.

Thu Mar 10, 2016 1:08 pm

I use 75/90 semi synthetic

Thu Mar 10, 2016 1:48 pm

HairyScreech wrote: I think that may have been one of the reasons BMW started using them.

Main reason was for use with DSC/ASC, etc. Plate type locking diffs. oppose the action of the electronics, while torsens behave themselves.

Thu Mar 10, 2016 5:21 pm

Thanks Guys.

Anyone know where I can get replacement gaskets and plugs for the backing plate? Also how much should the diff hold 1ltr?

Thu Mar 10, 2016 6:15 pm

Gasket and plugs from the main dealer, the normal lsd holds 1.7 litres.

Thu Mar 10, 2016 6:16 pm

1.7 ltrs and try BMW for the parts mate they won't be that expensive .

Thu Mar 10, 2016 9:27 pm

Back plate gasket is about £1 from BMW.

Thu Mar 10, 2016 11:32 pm

Brianmoooore wrote:
HairyScreech wrote: I think that may have been one of the reasons BMW started using them.
Main reason was for use with DSC/ASC, etc. Plate type locking diffs. oppose the action of the electronics, while torsens behave themselves.

Depending on the mapping, when programming pumps I can select a clutch differential in to the subroutine (depending on customer requirements).

Four channel traction systems are actually needed with torsion type differentials in order to preload the worm gears. Which is why you would never see a torsion on a race car, simply not good enough.