Synthetic Oil and Overdrive Transmissions

Hi Doug,

I have a question for you. 

I have been trying to find out if it is okay to use synthetic oil in the early Borg Warner T series 3 sp with od transmissions. I work on Hudsons, which use the R10 OD unit, then later the BW T86 and Studebakers which used the BW with OD transmissions.

Years ago I was told you could not use synthetic oil in them as it was “too slick” for the OD to work correctly. Now I understand that the oil needs to be compatible with brass parts that are in the transmissions and the Redline brand that I use is compatible
with “yellow metal” in transmissions and rear ends.

What is your thoughts on using synthetic oil in these units?

Thanks so much for your time!
 
Kerry
Wellborn, FL

Hello Kerry,

I don't have experience with the Redline Brand, but I do have experience with the Royal Purple. I know that you should not use the Royal Purple with yellow metal. It will turn your oil to a metallic yellow. In my case, it was dissolving the syncro rings. 

In my "stand alone" Borg Warner OD unit. I do use the Royal Purple for the reason, I believe it will withstand greater temperature than conventional gear oil will. The OD unit generates a tremendous amount of heat because of the large numbers of moving parts in a small space.

In standard application, whereas it is attached to the back of the transmission, it can dissipate the heat more efficiently. 

If your Redline Brand is compatible with yellow metal, I would say it is probably going to be a good thing to run, if you are pushing your transmission with more power than it was originally designed for, however if you are using it in standard application, conventional oil is probably adequate.

If you have a leak, it is generally more of a leak with synthetic. 

Hope this helps,
Doug