anybody problems whit gearoil from 80w90 to synt oil75-90?

[ton hamden]

hello:) i have to change the rearaxle fluid i have the y87 code on the car waths means lsd-3.42 in combination whit a/t i dont know which is int auburn or torsen, build of the car is 1month 98 in canada ,normaly is 80w90 hypoidoil in it from factory but can i change it for the full synth 75/90 from castrol or something whitout worrys about the seals on the front and the wheels and what about the noises from the rear because its thinner oil? or iam wrong about viscosity

[Vracer111]

Re: anybody problems whit gearoil from 80w90 to synt oil75-90?

http://www.frrax.com/rrforum/index.p...4&hl=gear+lube

I just switched to Redline 75W90 (still have stock open differential) and can tell when it gets up to temp as the rear end starts to really whine in 1st and 2nd gear on track, usually after 3-4 laps, not much noise change in 3rd gear and up.

[ton hamden]

Re: anybody problems whit gearoil from 80w90 to synt oil75-90?

thanks for reply :tup: ,i check the site www.torsen.com to and say you can put synt and mineral gearlube in the rearend ,so i decide to put the 80/90 mineral oil in it because the high speed drivings in europe is it better i think ,and the owners manuel says the 80w90 viscosity ,but when i have the auburn rearend on my car the people say from auburn that i only can use mineral oil 80w90 gl5 whit the treadment 4oz from gm .

[ReodDai]

Re: anybody problems whit gearoil from 80w90 to synt oil75-90?

If you're using an Eaton or Auburn diff do not put synthetic gear oil in your diff. Use the mineral oil and the gm lsd additive.

[ton hamden]

Re: anybody problems whit gearoil from 80w90 to synt oil75-90?

i have replaced today the oil in the rearend and its not a torsen and its a auburn or eaten i think ,you can see springs and plates, year of make is 1februari 1998 i put the 80w90 gl5 valvoline in it together whit 2 botlles aditive from gm thats enough i think thanks for the replys