Features:
- Fits 2001-2017 6.6L Duramax HD trucks
- Built for up to 500 horsepower
- Includes Raybestos C-3 and C-4 packs
- Extra clutch count for added holding power
- Randy's single disc billet torque converter
- Modified lock-up valve for better control
- Transgo trim valves enhance shift performance
- Comes with new bonded pistons
- Includes new C-1 and C-2 clutches
- All new bearings installed during build
- RatioTek pressure kit included
- Built to order with 3 week turnaround
A Stronger Transmission for Real-World Power
If you're building a 2001 to 2017 Silverado or Sierra HD with the 6.6L Duramax and plan to push it up to 500 horsepower, the Randy’s Transmission Stage 1 Allison 1000 is built with that goal in mind. This is not just a refreshed factory unit—it’s a purpose-built upgrade designed to handle more power and deliver smoother, more confident shifts under load. With Raybestos C-3 and C-4 clutch packs featuring added clutch count, this transmission is ready to handle the kind of torque that would overwhelm a stock setup. Whether you’re towing heavy, running a mild tune, or just need something more dependable than factory, this build steps up to the task.
Performance Where It Matters Backed by Proven Parts
Inside, you'll find new C-1 and C-2 clutches, bonded pistons, and all new bearings to ensure long-term reliability. A RatioTek pressure kit and Transgo trim valves are included to fine-tune pressure and shift quality, giving you better control and responsiveness. The single disc billet torque converter from Randy’s is the centerpiece of the upgrade, offering improved lock-up performance and greater strength under load. Every transmission is built to order with an average three-week lead time, and shipping includes a round-trip freight charge. If you're looking for a transmission that can handle the power without getting in the way of drivability, this Stage 1 build delivers the balance you need.
Fits: 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
Randy's Transmission 311241030 Stage 1 Allison 1000 Transmission | 2001-2017 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
Randy's Transmissions
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Randy's Transmissions
Randy's Transmission 311241030 Stage 1 Allison 1000 Transmission | 2001-2017 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
- SKU:
- RTS311241030
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Randy's Transmissions
Randy's Transmission 311241033 Stage 3 Allison 1000 Transmission 900HP Max | 2001-2019 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
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Randy's Transmissions
Randy's Transmission 311241031 Stage 2 Allison 1000 Transmission 700HP Max | 2001-2019 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
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Randy's Transmissions
Randy's Transmission 311241035 Stage 4 Allison 1000 Transmission 900+HP Max | 2001-2019 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax
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ATS Diesel Performance
ATS 309-842-4248 Stage 4 Allison LCT1000 Crate Transmission | 2001-2002 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LB7 2WD
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ATS Diesel Performance
ATS 309-822-4248 Stage 2 Allison LCT1000 Crate Transmission | 2001-2002 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LB7 2WD
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$6,538.95
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