311241031 Stage 2 Allison 1000 Transmission 700HP Max

Features:

• Supports up to 725 horsepower
• Fits 2001–2019 Duramax 2500HD/3500HD
• Stage 2 full Allison 1000 build
• Raybestos or ALTO G3 clutch kits
• Includes custom machined pressure plates
• Upgraded LML-style pistons and springs
• Ratio Tek pressure enhancement upgrades
• Transgo trim valves included
• Randy’s billet stator torque converter
• New OE transmission filters installed
• Heavy-duty cast aluminum deep pan
• Flexplate not included in retail builds

Built to Handle Big Power and Real-World Abuse

When you’re pushing serious horsepower through your Duramax, your transmission needs to be more than just strong, it needs to be ready for the long haul. Randy’s Transmission Stage 2 Allison 1000 is engineered to support up to 725 horsepower, making it the perfect match for high-output 2001–2019 Silverado and Sierra HD trucks. Whether you’re towing heavy, running aggressive tunes, or heading to the track on the weekend, this build is designed to take the abuse without flinching. It includes upgraded clutch packs using Raybestos or ALTO G3 torque kits in the C1 through C4 clutch assemblies, paired with custom-machined pressure plates to keep everything locked down when it counts.

Quality Components, Serious Performance Gains

This transmission isn’t just about brute strength. It’s packed with smart upgrades to improve longevity and shift quality, like LML-style pistons and return springs, Transgo trim valves, and Ratio Tek pressure upgrades. A set of new torrington bearings ensures smoother operation, while the included torque converter, featuring a billet stator, is built by Randy’s to match the rest of the system. It also comes with new OE filters and a heavy-duty cast aluminum deep pan to increase fluid capacity and help manage heat under heavy load. It’s a full build with premium internals from top to bottom, built by a shop that understands the real-world demands of diesel truck owners. Just note, flexplates aren’t included with retail or shop builds, and a $500 shipping surcharge applies. Still, if you’re building a truck that pulls hard and plays even harder, this is a transmission you can count on.

Fitment: 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax