2004.5-2005 GM 2500HD/3500HD 6.6L LLY Duramax Intercoolers

If you're looking to win back some of the performance lost from your 2004.5-2005 GM 6.6L Duramax LLY, check out our entire inventory of aftermarket Intercooler Upgrades! Upgrading to a new intercooler is a great way to run a more aggressive tune without running into a bunch of hassles down the road. Each one of these components is built stronger over stock and is much less susceptible to heat soaking, meaning you can stay out on the trail longer without losing power. You'll even experience a slight boost in both horsepower and torque, giving you an extra boost of confidence during those high-performance applications such as towing or off-roading. Pair your new intercooler with some additional Engine Upgrades or Turbo Upgrades to get unlock even more performance out of your Sierra/Silverado. GM Duramax Fitments: 2004, 2005 GM 6.6L Duramax. Submodel Fitments: WT, Custom, LT, LTZ, High Country, 1LT, 2LT, Pro, SLE, SLT, AT4, Denali. Some exceptions apply, please see individual product pages for specific fitments.