Which oil for LSD?

[NielsGalan]

I think I put some automatic transmission oil in there the last time, but I can't remember.

I was getting a wierd groaning noise form back there, when I read that I probably had the wrong type of oil in the Diff. The oil guy took a qualified guess and gave me what I think was automatic transmission oil. Worked like a charm.

Now I need to replace a seal down there and will be needing some more of the greasy stuff. What do I need??????

[Derek A.]

ummm. if you are running auto trans fluid in your diff its probably smoked. These units require a 75w90 or 80w90 gear oil. If you have a limited slip diff it should have the friction modifier additing in it. I would reccomend Redline 75w90 synthetic, it comes with the additive already mixed in.

[Rory]

I would reccomend Redline 75w90 synthetic, it comes with the additive already mixed in.
I second Reline 75W90 or if you want a local source Mobil 1 75W90.

Best,
Rory

[NielsGalan]

Would you by any chance know the Pennzoil equivalent?

[ryan roopnarine]

I think I put some automatic transmission oil in there the last time, but I can't remember.

I was getting a wierd groaning noise form back there, when I read that I probably had the wrong type of oil in the Diff. The oil guy took a qualified guess and gave me what I think was automatic transmission oil. Worked like a charm.

Now I need to replace a seal down there and will be needing some more of the greasy stuff. What do I need??????


bill's probably gonna hold his breath and make a "demure" response about what im about to say, as i've said it at least 10 times already, buuuuttt...

if the diff equipped on your car was spec'd for saf-xls oil (and i have no idea if it is as the US didn't get any 524td's or any diesel cars for that matter), it takes 75w140 synthetic oil. the lsd cars that made it to the us were spec'd for this oil. im sure a lot of people have perfectly functioning lsd units using heavy 75w90 oil (not a lighter one like mobil 1 75w90), but im just saying what the original spec is. if i were you and were dead set on using a 75 i'd pack it with LSD additive no matter what the bottle said. i've been down this road before and the 75w and additive didn't work well enough to leave alone.

[Kalevera]

You don't want the pennzoil equivalent :) I would just go with the redline 75w90 w/ LSD. It's in my 3.91S right now, works great. No noise, no nothing.

best, whit

[632 Regal]

I agree with Ryan that the LSD units are supposed to have the 140wt stuff and the opens use the 90wt.