2017-2019 Silverado & Sierra 2500 & 3500 Duramax L5P Complete Transmissions

The Duramax L5P under the hood of your 2017-2019 Sierra or Silverado 2500 or 3500 is capable of making some seriously huge horsepower and torque with even a few basic mods, but your factory Allison transmission, despite its strength, may not be able to handle it. Tier One's built transmissions for 2017-2019 Duramax L5P trucks can hold all the horsepower and torque your Duramax V8 can dish out, allowing you to add powerful tuning, big turbos, oversized injectors, and whatever else you have in mind without your transmission letting you down. We here at Tier One have Silverado & Sierra 2500 & 3500 transmissions that range from improved stock replacements that can handle heavy towing and bolt-on mods all the way to fully-built competition Allison transmissions that can handle over 1000 horsepower and aggressive track launches without letting you down. Make sure you also check out our 2017-2019 Duramax L5P Transmission Coolers or our 2017-2019 Duramax L5P Bypass Valves!