A friend of mine is replacing his transmission lube. I have 5 quarts of RP Synchromax leftover from another application. Can this be used on the Getrag or is it better get some synthetic 5W-30 ?

 

Might be the best thing for it. Better than motor oil, in any case. Er, synchromesh manual transmission case, that is.
(pun intended!)

 

Thats what I have in mine and it runs cooler, shifts easier, and is quieter. Really good stuff.

 

x3

It's good stuff, makes them more quiet, and smoother.

 

Been using it for a year with no problems.

 

what weight oil is that?

 

That's what I'm using. I used the RP 10w-30 for a year and that worked well but the G360 really seems to like the synchromax. I've had my top cover off my trans twice in the last year and everything still "appeared" brand new. Bearings looked good

 

Mine likes it even better than the Redline MTL - which ain't bad.
It's a little lighter than 5W-30 but not as thin as ATF.

 

The getrag doesnt seem all that picky, I ran 75/90 royal purple gear lube in it and then syncromax and it shifts very simular. Only difference I noticed is the gear lube shifted a little slower while cold. People on here run everything from the good stuff to cheap 75/90 gear lube, to cheap 5w30 motor oil. I think its just a workhorse of a transmission.