additional transmission cooler 2004 Trailblazer

[bradleypa]

I would like to install an additional transmission cooler for our big 10 state tour this summer towing our camper. I need to know which line at the bottom of the radiator is the return to the transmission line. I Can't find a single illustration showing me the right one.

Thanks
Bratley

[maxwedge]

One way to tell is the return line is noticeably cooler. Should be the l/s though.