Recommended Transmission Cooler and Parts Needed for Installation on 2011 GMC Sierra

Question:

2011 lml gmc sierra 2500hd 6.6l duramax with allison 1000 6 speed. i want to put a secondary transmission cooler on my 2011 lml diesel GMC Sierra. i want best cooling, fan option and easiest connection to existing factory system. i am currently installing a mishimoto radiator along with intercooler, so transmission needs additional cooling. i already have a ppe deep pan with additional fluid capacity. please send me a list of parts needed for a complete install. i envision mounting the cooler above on left of existing cooler already on truck as you have a listing posted on 2011 youkon or tahoe? let me know to order. thanks

asked by: Joseph C

Expert Reply:

For your 2011 GMC Sierra I recommend using a Derale 10,000 Series Stacked-Plate Cooler with -10 AN Fittings, like # D52510. I spoke with my contact at Derale and he said these coolers are popular among Allison transmission owners.

When choosing a transmission cooler, the largest cooler that will fit in the space available in your engine compartment is typically the best. Generally speaking, the larger the cooler the better the cooler performance. A stacked-plate cooler is the most efficient type of aftermarket cooler.

The # D52510 that I referenced above is a 25 row, Class V cooler that measures 13 inches wide x 9-9/16 inches tall x 2 inches deep. To mount this cooler, you can use the Bracket Kit for Derale High Performance Stacked-Plate Coolers # D50020. Since your Sierra already has a factory cooler, if you do not have enough room for the # D52510 cooler, the # D51910 cooler is a 19-Row, Class V cooler that measures 13 inches wide x 7-9/16 inches tall x 2 inches deep.

If you'd like a stacked-plate cooler with a fan, the largest option is the Derale Hyper-Cool Extreme Remote Cooler Assembly with Fan, -10 AN Inlets, Class V # D15875. This cooler measures 13 inches wide x 14-7/8 inches tall x 5-5/8 inches deep. This is a fan-mounted, remote cooler that features the most efficient type of heat exchanger core, a stacked plate cooler, and an 800-CFM waterproof fan. You will want 4-each 1/4”-20 bolts, 1/4” washers & 1/4” lock nuts (not included) to install this cooler.

You can view all of the Derale coolers with -10 AN fittings on the linked page.

To connect the -10 AN fittings on either cooler to transmission lines, you will want 2 Derale -10 AN Female Swivel x 1/2 Inch Barb Hose Fitting # D98203. Hose clamps # D13008 will keep the hoses connected to the barb fittings.

The best place to install a cooler is at the front-most space of your engine compartment so the air flows through the cooler first. However, when using a cooler with a fan, the cooler can be mounted wherever there is room, since the fan does the cooling rather than the air flow while driving.