Should a Transmission Cooler Go After the Factory Cooler on a 2005 Chevy Silverado 2500HD

Question:

I have an 05 2500hd with the factory auxiliary cooler and I want to install the cooler u guys sell part #d13503 and I read on another one of your answers that they need to be hooked up in series with the factory cooler coming first. My question is how do I hook the aftermarket cooler Im series? Do I take the return line from the factory cooler and put that to the in on the new cooler and then from the out on the new cooler back to where the factory return line went? Thanks in advance.

asked by: Trevor H

Expert Reply:

The recommended flow path when adding a supplemental transmission cooler like # D13502 is from the transmission to the factory cooler, then to the supplemental cooler, and finally back to the transmission. You may also need an additional fitting to avoid cutting and flaring lines. The correct fitting depends on the engine in your truck.

If you have a 4.3 liter or 8.1 liter, use fitting # D13018. For any other engine size use # D13035. I have included some links on transmission coolers for you.

expert reply by: Michael H