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This 2001-2014 Chevy / GMC 6.6L Duramax Transmission Cooler is now available! Click here to check it out!

Extreme heat is always the enemy, especially when it comes to vehicles equipped with an automatic transmission. The Allison gearbox mated with your 6.6L Duramax is no exception. With the high temperatures produced by an automatic transmission, it seems almost cruel that the sweltering summer heat comes when most of the towing of campers, boats, and other outdoor toys happens. GM did include some help to keep your gears cool. Unfortunately, it's a little small.

For such an iconic towing machine, it seems strange to equip it with such a small transmission cooler.

While the 9 rows on the factory cooler keep the transmission cool enough during regular driving, it shows its limited cooling abilities once a few thousand pounds are attached to the rear of the truck.

Before we start with the adorably small transmission cooler on the GM Duramax, some of you might be wondering why this extra