Outer Limits 4x4 Board

Hey Guys,

I have just purchased a 100 series with front and rear air lockers from my uncle.

He told me that he was told to use limited slip diff oil in both the front and the rear because of the lockers. (He has hardly ever used the lockers other than keeping them active every so often).

I thought I would ask the guys at ARB in dandy and he said not to use limited slip diff. Rather he suggested 85w 140?

What should I do? Should I change it over or will running lsd oil cause any issues?

My uncle says that the ARB guys in brissy told him to use lsd diff oil front and rear specifically for the lockers?

Well sounds like they all dont have a clue and that arb doesnt talk with eachother. Im pretty sure you are suppossed to use lsd for the friction factor. But someone put open centre oil in my lockers. Hasnt done a thing and no difference. I honestly dont even know if it matters so dont worry too much about it. Only worry if there is NO oil.

I can't see why you would need the LSD oil in with air lockers. LSD oil is formulated to work with the clutch or friction type action of the LSD. Air lockers don't work the same way. They're either locked or working like an open diff. If it were me, I'd be going with a 75W140 gear oil.

I run straight 90w in My lux with the locker and never had a problem

Castrol LSX 90 is what was recommended to me by ARB, ran it in the 80 series and running it in the 100 as of today now the lockers are fitted.

My diff guy recommends 85/140, ive been running it last 7 years no probs

Castrol LSX90 for me too. Run it in the air-locked rear diff and the standard front.
It is true, you can't seem to get a definitive answer out of some of these sales guys.

I understand limited slip diff oil just handles the heat better? And that the only reason not to use (correct viscosity) lim. slip oil is the cost.

I use castrol APX80W90 in both my diffs (as specified in castrol guide). Have had issues but i suspect they're unrelated to the oil - arb locker in front is fine as is detroit locker in rear.