Which Transmission Line to Install a Transmission Cooler on for a 2010 Chevy Suburban

Question:

I want to install a transmission cooler # 13504 on my 2010 chevy suburban The easiest access I see is the transmissions lines after I remove the rock guard. I see that one line has 2 barbs that I can cut between them and install the hoses with the clamps. but Im not sure if that is the return line because it seems to be the hotter of the two but Im not sure. It is also the line that comes from the upper part of the radiator. I dont want to cut without being 100 sure. Can you help me with choosing the correct line to cut.

asked by: Emilio A

Expert Reply:

The method we use that has proven to be 100 percent reliable for determining which line to use for installing a transmission cooler is to start off with the car totally cooled off. Letting it sit overnight would be ideal.

Start the vehicle and put it in drive, brake torque it slightly (apply the brakes firmly and then raise the RPM's by lightly pressing the accelerator) and then put the vehicle back in park and turn off the ignition.

The cooler of the two lines is the return line and the one to use for installing the Derale Transmission Cooler part # D13504 that you referenced. I attached an install video and an FAQ on transmission coolers for you to check out as well.

expert reply by: Jameson C