G'day all, Quick question / thoughts on diff oil for my TT. I know the service manual recommends 80W-90 oil (API GL5), but I have got some Motul Gear Oil 75W-80 (API GL4 / API GL5). I know this is fine for the manual trans but will it do for the diff? I have been told it should be fine, but I am hesitant to put an incorrect weight in a viscous LSD.... Anyone got experience with this?
The viscous fluid part is isolated from the diff oil in any case. BUT I would use the correct weight oil. It may stop clicking, wining and higher wear. The Amsoil or the redline MT90 isnt too expensive and you only need a few litres
Don't use MT90 in the diff....... Redline list MT90 as their gearbox oil (GL4) I suggest you use their 75W90 Gear Oil in the diff, it contains lsd friction modifiers and is designed for this application. Redline is made in the US so you'll have to buy 2 Quarts (remember quarts ? i.e 2 pints). Nissan reckon you'll need 1.5 litres but I never have any left over from the Redline bottles, so that makes it 1.8927 litres in my book
I was interested in why MT90 couldnt be used in a diff so i sent off an email to redline. Here is their response. Graham Thank you for contacting Red Line Oil, the reasons I wouldn?t recommend the MT-90 in most differentials are: most rear differentials call for a GL-5, MT-90 is a GL-4, a friction modifier is needed to control chatter from a clutch limited slip also beneficial otherwise, MT-90 doesn?t contain very much and it may not match the viscosity called for. Regards, Dave Red Line Oil
