2007.5-2010 Silverado & Sierra 2500 & 3500 Duramax LMM Complete Transmissions

The Duramax LMM under the hood of your 2007.5-2010 Silverado & Sierra HD can make a ton of horsepower and torque with relatively few modifications, but your truck's stock transmission may have a hard time holding it. Tier One's built transmissions for 2007.5-2010 Silverado & Sierra 2500 & 3500 Duramax LMM trucks are designed to hold all the power your Duramax V8 can spit out. This allows you to use extremely powerful tuning, upgraded turbos, and oversized injectors without worrying about your transmission letting you down. We have everything from budget-friendly HD tow transmissions meant for heavy hauling to all-out competition transmissions that can hold over 1000 horsepower and survive hard launches at the track. Even the best transmission build needs a reliable connection to the engine, so if you are piecing together your own build or need a specific stall speed, look at our 2007.5-2010 Duramax LMM Torque Converters. Protect your investment from heat while towing by adding one of our 2007.5-2010 Duramax LMM Transmission Coolers. If you aren't ready for a complete transmission swap but want to fix shifting issues, a valve body replacement is a great place to start, so check out our 2007.5-2010 Duramax LMM Valve Bodies. To get the most out of your new transmission, consider upgrading your fluid capacity or installing a thermal bypass valve from our section of 2007.5-2010 Duramax LMM Transmission Parts.