Diff Oil, What To Use?

[reNEGaDe88]

I am not sure now what oil to use in the diff for my R32 with a viscous LSD.

I have done heaps of reading up on DIFF oil. But I am not sure what to use.

I have a R32 GTST factory VISCOUS LSD rear diff, but R33 GTST engine and box.

Some workshops recomend Motul Gear FF-LSD Type 2 Oil. But its not an active LSD, so it doesn't need the friction modifiers that 1.5 or 2 way LSD's need. The vicous oil that makes the LSD lock up it seperate to the other oil in the diff.

So do you a slippery oil to allow the diff to spin nicely and not wear, or do u need a sticker oil for the diff to stay lube'd up when u thrash it?

Otherworkshops recomend Castrol SAF-XA or LSX90 or Syntrax or EPX80w90 or VMX80.

Nissan recomend 75w90 oil for the gearbox, similarly the diff. So would running a 80w140 oil be bad?

Other's say that Redline lightweight shock proof is also good. But that stuff is very slippery and has had peoples diff's lock up too much around round abouts etc.

Motul 90PA Differential Oil is what I plan to get, its a good mineral oil, I don't know if fully synthetic is necessary for a factory VLSD.

The diff's are hypoid right, so do the oils need to specify that?

Whats your opinion?

[reNEGaDe88]

Hey there mate, I have an S15 which is about to go in for a FULL service(diff, gearbox,brakes, plugs, radiator etc). I went for Motul 8100 XS 5w-40 full synthetic for the engine, Motul Gear300 75-90 for the gearbox and Motul GEARBOX 80-90 mineral for the diff. DO NOT use Motul FF-LSD if you have the stock LSD!!!! I know this sounds very strange but the S15 manual says to use NON-LSD oil for the gearbox and diff(which GEAR300 and GEARBOX are NON-LSD). I think FF-LSD is to be used with lockers and mechanical diffs. Bear in mind you could use GEAR300 for the diff also, i opted not to because the manual states the S15 diff needs 80w90, not sure if i could get away with using full synthetic Gear300... would love to try it for the diff sometime.

It appears we should not use LSD oil in the diff. So I am leaning towards Castrol EPX 80W/90W or Motul Gear 300. As they are non LSD oils

Edited May 11, 2009 by reNEGaDe88

[reNEGaDe88]

I went with Gear 300 as you only need to change diff oil every 80,000km. Considering its $40/L which is pretty much a one off for the 1.8L diff oil I need Will let you boys know how it is when its in.

[samps]

It appears we should not use LSD oil in the diff. So I am leaning towards Castrol EPX 80W/90W or Motul Gear 300. As they are non LSD oils

I just spoke to Garry Rogers (large Nissan dealership in Melb) and they reckon LSD oil is required for the S15 6spd manual (helical). Where did you hear that it shouldn't be LSD oil?

[Kinks]

Viscous LSDs are a sealed unit, use non-LSD oil. I put Gear 300 in my gearbox and diff and it is fantastic.

S15 diffs are Torsen, they use gears instead of clutch packs to perform the LSD function therefore you do NOT need friction modified LSD oil. You only need friction modified oil on LSDs that use clutch packs.