im running in my sc300 currently and doesnt feel that great, my tranny actually feels rougher

 

Is the Royal Purple 75w140 a good choice for a rear Torsen diff?
(or should I go with a slightly lighter gear oil?)

thanks

 

are you running W58? I'm running RP 75w90 on my W58, runs great, but I'm running on the good ol open differential

 

I planning on swapping to my R154 soon
still waiting on a few more parts and time

I plan to use the Royal Purple 75w140 in the R154
just need to know how much to order at the moment (whether the torsen can use it too)

 

Most 6 speed trans guys will tell you to run RP syncromesh well talked about on the supra forum.

 

Yes the V160 trans runs on ATF fluid so go ahead and use that. Don't do what i did and put it into the W58 or R154 as they both use thicker gear oil. Running the Syncromax oil will tear up your transmission very quickly. I Have RP 75W-140 in now and works fine.

As for the diff oil service manual calls for SAE 90 or SAE 80W-90 oil for the diff. This goes for both Torsen and open diffs.

 

looking at the Royal Purple site
80w90 for the rear diff only comes in a 5 gallon pail
http://www.royalpurple.com/gear-oil-pp.html

Anyone use the 75w90 in the rear diff? at least that comes in quarts

 

I got a deal on 12 individual quarts of Royal Purple 75W140
but I don't need so much, I only need 7qts
any one in NYC want to buy 5 quarts @ $11 each?

 

I'm using red line for my 200k mile w58 and it's great.

red line ftw :P