Chevy & GMC 2500 & 3500 Allison Transmissions & Transmission Parts

The stock Allison transmission helping power your 3500, 4500, or 5500 Silverado or Sierra may be an upgrade over the base GM transmissions in the 2500 trucks, but with the huge power and towing capabilities of your tough Duramax truck, even the mighty Allisons may find themselves lacking. Tier One's built Allison transmissions for HD GM trucks can handle enormous levels of horsepower and torque so that you can stock on aggressive tunes, bigger turbos, oversized injectors and other Duramax performance mods. Our built Allison transmissions can also handle heavy towing, sled pull competitions, drag racing, and aggressive off-roading without breaking a sweat. Also check out our Allison transmission rebuild kits or our 6L90E built transmissions for the 2500 trucks! Contact Tier One with questions or for custom builds!