i have fast coolers installed and royal purple synchromax in the tranny, i normally never see over 120* in the 6 spd tranny even during warm weather.

uesterday i worked the truck hard driving a steady 80mph for 150miles without stopping, and noticed that my tranny was getting into the 160-170*range...does anyone think this is high for a manual tranny especially with te additional coolers added to it???

 

Sounds fine to me. You don't need to worry about the trans temp until you start pushing 230. The Fast Coolers are next to worthless.

 

15 minutes of 70mph and my getrag is pushing 215...running empty 170 sounds like a happy temp to me