TR2/3/3A TR3 OD Trans & Diff Fluids?

[karls59tr]

I think this was recently discussed but I cant find the link. Was the upshot that Redline MT90 would be the best choice for a new trans? Also was the MT90 also suitable for the Diff or was 70/90 the oil of choice?

 

[TR3driver]

I'm not sure there was any clear consensus. My opinion, MT-90 is entirely suitable for a new TR3 trans, with or without OD. There may be less expensive alternatives that will work fine, but the MT-90 makes a noticeable improvement in shifting.

Again, my opinion, MT-90 is not the best choice for the rear axle. Redline has stated that it will work (and I believe them), but you are paying a lot of money for an oil that is designed to optimize synchomesh operation, and then installing it in a non-synchromesh unit.

Personally, I prefer Valvoline full synthetic gear oil (GL5 75W-90) for the diff. It is half the price of the MT-90, and available at my local Autozone/O'Reillys if I discover I need a quart at 9 PM on a Saturday night. The GL5 rating means it provides better protection for the gear teeth, and it contains none of the sulfur-based additive that some GL5 (and GL4) oils use, which over time can erode the brass thrust washers.

 

[sail]

I put in MT-90 on Randall's suggestion after freaking out on the test drive of my rebuilt gearbox. I could feel a difference. That and care in driving when it's cold and all is good.

 

[GilsTR]

After having several different issues with my rebuilt OD tranny-
We put in the Redline. Not sure that was the answer...but I can tell you it does work well now. gil NoCal

 

[tdskip]

30w non detergent is also a fine choice for an OD. Not contradicting the advice above, just saying this is another acceptable option.