Features:
- Built for 2003-2004 LB7 Duramax 4WD trucks
- Includes ATS performance LCT1000 transmission
- Equipped with Five Star billet torque converter
- Deep transmission pan improves cooling capacity
- Optimized for towing and heavy-duty driving
- Stage 1 upgrade for reliable performance
- Improved torque handling over factory unit
- Supports moderate power and tuning upgrades
- Ideal for daily drivers and work trucks
- Dyno-tested for consistency and durability
- Compatible with stock and mild-modified setups
- $500 shipping surcharge applies at checkout
Bring Your Truck Back To Life With Confidence
If your early 2000s Duramax isn’t shifting the way it used to, this ATS Stage 1 Crate Transmission is a game-changer. Built specifically for 2003 to early 2004 LB7-powered Silverado and Sierra 2500HD and 3500HD trucks, it’s designed to breathe new life into tired drivetrains with smooth shifts and dependable towing power. Whether you use your rig for hauling heavy loads, weekend toy haulers, or just reliable daily driving, this transmission delivers the confidence you want behind the wheel. With a billet Five Star torque converter and a deep pan included, you’re not just getting a basic replacement, you’re upgrading to long-term durability and heat resistance. It’s ideal for owners who don’t need a race-ready setup but still want superior reliability over the stock unit. And because it's been engineered by ATS, you know it’s been tested, refined, and ready to handle whatever you throw at it. This is your opportunity to get that factory feel with the peace of mind that comes from modern performance.
Built With Precision For Everyday Heavy Duty Demands
Under the hood, the ATS 309-814-4272 transmission offers a complete factory-fit solution backed by serious internal upgrades. The LCT1000 base is fully reworked by ATS with a focus on durability, featuring improved clutch packs, recalibrated hydraulic circuits, and precision machining for optimal gear engagement. The included ATS Five Star torque converter boosts torque multiplication and lowers transmission temps under load, which is a huge plus for frequent towing or off-road use. Paired with the deep transmission pan, this package increases fluid capacity and improves thermal regulation, extending the service life of the entire drivetrain. Designed for trucks with Power Take-Off (PTO), it’s a great option for utility or work truck applications that demand consistent reliability. This setup is especially useful for customers running mild engine tunes or upgraded injectors and turbos. It’s built to meet the demands of a modern workload while staying true to the truck’s OEM fit and function.
Fits: 2003, 2004 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LB7 4WD
Notes: Great, based on the same product above, can you make me a list that prioritizes key notes from the manufacturer (MFG) page from this product page that you think might be valuable for our customers to know? Not really features like the list above, but things to consider before buying. I need the following as an untitled list in HTML code:
ATS 309-814-4272 Stage 1 Allison LCT1000 Crate Transmission | 2003-2004 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LB7 4WD
ATS Diesel Performance
MSRP:
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$5,363.95
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ATS Diesel Performance
ATS 309-814-4272 Stage 1 Allison LCT1000 Crate Transmission | 2003-2004 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LB7 4WD
- SKU:
- ATS309-814-4272
- UPC:

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ATS Diesel Performance
ATS 309-824-4272 Stage 2 Allison LCT1000 Crate Transmission | 2003-2004 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LB7 4WD
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$6,538.95

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ATS Diesel Performance
ATS 309-834-4272 Stage 3 Allison LCT1000 Crate Transmission | 2003-2004 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LB7 4WD
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MSRP:
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$7,331.95

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ATS Diesel Performance
ATS 309-835-4272 Stage 3 Allison LCT1000 Crate Transmission | 2003-2004 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LB7 PTO 4WD
MSRP:
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(Inc. Tax)
MSRP:
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$7,331.95

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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
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MSRP:
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$8,081.95

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ATS Diesel Performance
ATS 309-865-4272 Stage 6 Allison LCT1000 Crate Transmission | 2003-2004 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LB7 PTO 4WD
MSRP:
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$10,611.45
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