What's the best diff fluid for 3.76LSD? Read through many old threads!
 

So, I searched a crapload and some threads say that friction modifiers are needed and some say that friction modifiers are NOT needed for this diff...which is it?

I have the 3.76 LSD (Supra TT; Torsen type LSD). I currently have 75w90 Royal Purple Gear Lube in there and it seems to work OK but every once in a while I hear noises from the rear end...especially during slow turns (i.e. parking lots). The unit was brand new and I never changed out the initial fluids...I think I read somewhere that after the first 1000-2000 miles it should be changed out if the unit was brand new; perhaps to get rid of metal shavings and etc. So, I am changing some other fluids soon so i figured I would change the diff fluid as well.

What do you guys think? Thanks! :thumbup:

In the past, I used to change out the supra TT rear diff with royal purple or redline fluid. But I was once given two quarts of amsoil gear oil and changed it out in my car in which I felt a noticeable difference in noise. FWIW, I change out my rear diff fluid every 25k miles/2 year.

Did the noise get worse or better (quieter) with the Amsoil?:uh:

Sound Peformance known for building some of the fastest supras out there told me they run Valvoline synthetic 75w90 in their race car.

...cool. Well, on that note I see you too have the 3.76 LSD; what do you use, or have you used in the past?:uh:

The noise is definately quieter. But then again, I rarely hear anything behind the driver seat because I'm too busy enjoying the music from the turbos or Sc'd..:D

I listened to them and went with the Valvoline and as of now no noises or any issues. They told me that its not needed to run the $17/bottle royal purple unless you like wasting money. Now don't get me wrong cause I do use royal purple engine oil, but something so simple and mechanical as a torsen rear diff..I could see their reasoning.

I always have my radio on :)

and as far as the diff oil...money should be no object since you rarely change it out anyhow.

btw, walmart has 0w-30 fully synthetic motor oil.

I agree with Alexus 300. Amsoil FTW! I am getting ready to do my 60K and I will be switching over to all Amsoil fluids.

http://www.amsoil.com/company.aspx

http://www.amsoil.com/video/company/index.aspx

RP in my poopura rear end.
but I didn't pay for the RP :p.
No complains here.

Valvoline 75w90 with GM or Kendall LSD additive.

For those that don't know, Amsoil is one of the very few companies that I know of that makes a 75w-140 gear oil. There pricing is actually cheaper than Royal Purple if you get it through one of their dealer with a discount. I think I pay around $10/quart and if I purchase in large quantities, I get an additional 15% off which comes out to be pretty cheap.

this ok for oem rear ends? i no longer have my 3.76 installed, im back on the OEM gs430 diff

I thought no matter what you have to stick to 75w-90 diff fluid? What do these numbers actually mean? and is this a good weight for NY weather? (ranging from -5 to 100 degrees depending on the season)

From the factory, supra's require 80w-140 but it's hard to find it so amsoil is the closest thing. But on the stock non-lsd diff on 95% of GS out there, just go with the 75w-90 and you're set.