Forum Discussion

LVJJJ's avatar
LVJJJ
Explorer
Dec 29, 2015

Trans cooler fliud route

Although I've been towing for years, and have always had a transmission cooler on every tow vehicle, I can't remember whether the fluid should come from the trans thru the cooler then to the rad and out back to the transmission, or vice versa?

In other words before or after the the radiator?

Recently purchased an '04 GMC Envoy to tow our 4000 TT, has tow package but no cooler. On the Trailvoy forum, there didn't seem to be a consensus as to which way it should be. Since those using their Trailblazer or Envoy for towing was a minority, I'm thinking us RV'ers here would know best.

The climate you live in seems to be the reason for placing the cooler before or after?