Features:
- Complete Stage 4 transmission performance package
- Built for 2003–2004 6.6L LB7 Duramax trucks
- Includes Five Star torque converter upgrade
- Features billet input and output shafts
- Comes with ATS deep transmission pan
- Includes ATS Co-Pilot transmission controller
- Designed for 4WD with PTO-equipped models
- Handles high torque and horsepower applications
- Improved shift quality and clutch engagement
- Enhances towing, racing, and off-road performance
- Increases transmission cooling and fluid capacity
- $500 shipping surcharge applied at checkout
Upgrade Your LB7 With A Transmission That Can Keep Up
If your LB7-powered truck is making serious power, it’s time to ditch that tired stock transmission and drop in something built to handle the heat. The ATS Stage 4 Allison LCT1000 Crate Transmission gives your 2003–2004 Silverado or Sierra 2500HD or 3500HD the strength and control it needs to keep up with your build. This isn't just a transmission upgrade, it's a full performance package including a billet input shaft, billet output shaft, ATS Five Star torque converter, and a deep pan to keep temps in check. Whether you’re towing heavy loads, running down the drag strip, or daily driving with extra power under the hood, this setup delivers smooth, reliable shifts and long-term durability. It also includes the ATS Co-Pilot transmission controller, giving you intelligent pressure control and enhanced shift timing. With PTO compatibility and 4WD support, this crate transmission checks every box for high-performance and hard-working trucks alike. Built to take abuse and keep going strong, it’s the upgrade your LB7 has been waiting for.
Built For High Torque Pressure And Performance Stability
The ATS 309-845-4272 Stage 4 Allison LCT1000 Transmission Package is engineered specifically for 2003 to early 2004 GM 2500HD and 3500HD Duramax trucks equipped with the LB7 engine and 4WD with PTO. This complete transmission system includes key performance components like billet input and output shafts for greater strength under extreme torque, a Five Star torque converter to enhance torque multiplication and drivability, and a deep transmission pan to increase cooling capacity and fluid life. The heart of the control system is the ATS Co-Pilot, which fine-tunes line pressure and shift strategies to ensure smoother gear transitions and better transmission response under load. This Stage 4 package is ideal for trucks that have been modified beyond factory horsepower and torque levels, offering improved clutch engagement, reduced slippage, and much higher holding capacity. All components are designed to work together seamlessly to reduce stress and increase longevity of the transmission under heavy-duty use. Whether you’re using the truck for heavy towing, racing, or high-output work, this transmission provides the reliability and control needed to handle serious performance. A $500 shipping surcharge applies due to the weight and freight class of the complete assembly.
Fits: 2003, 2004 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LB7 PTO 4WD
Notes:
- Fits 2003–early 2004 Silverado/Sierra 2500HD and 3500HD with 6.6L LB7 Duramax
- Designed for 4WD models with PTO provision
- Includes ATS Stage 4 LCT1000 performance transmission
- Comes with ATS Five Star torque converter
- Includes deep transmission pan for increased fluid capacity
- Features billet input and output shafts for added durability
- ATS Co-Pilot transmission controller included for advanced shift control
- Ideal for trucks with high horsepower and towing applications
- Built to handle increased torque and prevent transmission failure
- $500 shipping surcharge will be applied at checkout
ATS 309-845-4272 Stage 4 Allison LCT1000 Crate Transmission | 2003-2004 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LB7 PTO 4WD
ATS Diesel Performance
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ATS Diesel Performance
ATS 309-845-4272 Stage 4 Allison LCT1000 Crate Transmission | 2003-2004 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LB7 PTO 4WD
- SKU:
- ATS309-845-4272
- UPC:

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ATS Diesel Performance
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ATS 309-844-4272 Stage 4 Allison LCT1000 Crate Transmission | 2003-2004 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LB7 4WD
MSRP:
Was:
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(Inc. Tax)
MSRP:
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$8,081.95
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