2015 Silverado Transmission Cooling Upgrades

Keeping transmission temperatures under control is an important part of protecting your vehicle, especially when running larger tires, towing, or putting your truck to work.

In this project, I'll walk you through the transmission cooling upgrades I made to my 2015 Chevrolet Silverado 1500 equipped with the 5.3L V8 and 6L80 transmission.

The Upgrades

Mishimoto Transmission Cooler Installation

I'll show how I installed the Mishimoto transmission cooler, including removing the front grille, mounting the cooler, routing the new transmission lines, and bypassing the factory cooler.

Sure-Cool Thermal Bypass Modification

I'll also cover the Sure-Cool thermal bypass modification, including removing the factory bypass valve, replacing its internal components, and reinstalling the assembly.

Real-World Temperature Results

With the Mishimoto cooler installed and the factory thermal bypass unchanged, my transmission typically operated around 196–198°F.

After installing the Sure-Cool modification, I recorded typical operating temperatures of approximately 143–153°F during a mixed city and highway drive, with a peak of 153°F.

These are my actual observations, not a guarantee that every truck will experience the same results.

Follow Along

I'll be sharing installation walkthroughs, photos, parts information, and videos documenting these upgrades.

Learn the Skills. Share the Knowledge!