Installing Derale Transmission Cooler in 2006 GMC Yukon Denali XL

Question:

Hello Guys! just purchased a Derale 8000 transmission cooler from you for my 2006 Yukon Denali XL. I am wanting to place the new cooler behind the old one for increased cooling capacity. Which line on the old cooler do I cut to splice in the new one? Or, do you recommend just replacing the smaller stock radiator with the new one? I reached 270 degrees after installing a new transmission while only pulling 6500 lbs...need as much cooling as possible! Thank you!

asked by: Chris M

Helpful Expert Reply:

Thanks for the purchase and to answer the question about replacing the radiator on your 2006 GMC Yukon Denali XL, that is not something we recommend because the Derale Series 8000 Plate-Fin Transmission Cooler Kit # D13504 you got is an accessory cooler that works in conjunction with your factory cooler. Also keep in mind you do need Derale Snap-In Radiator Adapter Fitting for GM # D13035 to install this cooler on your Yukon.

In regards to the line on the old cooler, what you need to do is find the return line, which is pretty simple to do. Just start up your Yukon and put the car in drive for 10 or so seconds. Then put it in park and turn it off; there are two transmission lines and you need to feel both. The cooler of the two lines is the return line!

I have added a link to the install instructions as well as a link to a video showing a cooler being installed on a Yukon XL for you to take a look at.

expert reply by: Kyle S