Rear Diff

[arcangel07]

I have a 89 Turbo Supra Automatic, I just bought it from a friend, and I noticed that there was a soft grinding or wineing noise from the rear, I first thought it was my breakes, but then I checked the rear diff, very expensive looking BTW, and it was bad, so I need to change it, anyway on to my question, what fluid should I add into the rear diff. Thanks

[bgrieger]

Any gear oil meeting the owner's manual with LSD friction modifier should do. I prefer redline mixed with ford modifier myself, but your preferred brand will likely be fine for the diff if it meets requirements. I only find the trannies complain about different formulations from brand to brand myself.

Check to make sure it is an LSD unit though (will have it right on the casing, by the drain or fill plug).

[Jeeves]

2.2: Differential Carriers

Another condition that may trouble your Supras differential is lack of regular oil changes; this will lead to differential failure or premature wear out. The MA-70 differential holds a very small amount of oil so it needs to be changed regularly. Cold climates are very hard on the differential. I recommend using a good quality synthetic in cold climates. I do not recommend standard 80/90 wt oils in any Toyota differentials used in cold climates. Using 75/90-wt LSD differential carrier oil from Ford motor company makes Supra differentials run quieter and smoother than any other oils tested.

Some LSD differentials in MA-70 and MA-71 cars have excessive LSD {limited slip differential} cage pressure causing premature clutch pack failures after some cars have become stuck in mud or snow, I have opened up badly abused differentials where the LSD oil is completely burnt and Dried up from the heat of one wheel smoking while the other is locked. If you notice some chattery noise from the rear of the car when turning corners donít panic: you have a supra with a very tight LSD differential carrier. On a Supra with tight LSD you can avoid the above clutch pack failure by using the previously mentioned LSD differential carrier oil from Ford motor company. This oil has increased protection for the clutch pack and has proven to be the best differential oil for all Supras from 1982 to 1992. Don't ask me why, all I can say is this oil works like magic. Note: A number of club members are using synthetic oils from Amsoil and Esso in their differentials with good results, one word of caution should be noted." Synthetic oils may make a some differentials that are already noisy, noisier."

[arcangel07]

Thanks for the help, I am going to order someof that oil today and see how it works, surely it will be better than what is in it now.