SKU: ATS309-824-4272

Stage 2 Allison LCT1000 Crate Transmission

Ships From Manufacturer in 15-20 Days
Confirmed fitment below
YEARS
2003-2004
MAKE / MODEL
GM/Chevrolet/GMC / Silverado/Sierra
SERIES
2500HD/3500HD
ENGINE
6.6L Duramax LB7/6.6L Duramax LLY
Price
$6,994.99
or
American Express
Apple Pay
Diners Club
Discover
Google Pay
Mastercard
PayPal
Shop Pay
Visa
Free Shipping
ORDERS $70+
Easy Returns
HASSLE-FREE
Earn Rewards
ALLIGATOR POINTS
Not sure this fits your build?
Our diesel experts know these trucks. Call or chat before you buy.
1-208-719-7400

PRODUCT DETAIL

Key Features & Description

Features:

  • Fits 2003-2004 6.6L LB7 Duramax 4WD
  • Includes ATS performance-built LCT1000 transmission
  • Comes with ATS Five Star torque converter
  • Features ATS deep transmission pan
  • Includes ATS Co-Pilot transmission controller
  • Improves shift quality and torque capacity
  • Enhances towing and performance capabilities
  • Increases cooling and fluid capacity
  • Complete bolt-in transmission package
  • Built for heavy-duty and high-power builds

Durability and Control for Your LB7 Workhorse

If you’ve been pushing your 2003–2004 GM Silverado or Sierra 2500HD/3500HD with a 6.6L LB7 Duramax and feel your stock transmission holding you back, the ATS Stage 2 Allison LCT1000 Crate Transmission Package is exactly what you need to bring your truck up to the task. This complete, bolt-in solution is designed for 4WD trucks and comes fully equipped with ATS’s performance-built LCT1000 transmission. It includes the proven ATS Five Star torque converter for better torque management and improved low-end drivability, making it ideal for towing, hauling, or running added power. The package also features ATS’s deep transmission pan, which increases fluid capacity and helps manage heat during demanding driving conditions.

Advanced Shift Control and Heavy-Duty Performance

What makes this package stand out even more is the ATS Co-Pilot Transmission Controller. This advanced control module fine-tunes your transmission’s shift timing and torque converter lock-up, giving you better control and protection when the workload increases. Whether you’re daily driving, towing heavy trailers, or tackling performance upgrades, this package delivers a noticeable improvement in drivability and durability. It’s designed to handle real-world demands and eliminate the common failure points of the factory transmission. Just keep in mind that this package ships via freight, and a $500 shipping fee will apply at checkout. It’s a small price to pay for peace of mind and long-term transmission reliability.

Fits: 2003, 2004 GM Silverado/Sierra 2500HD/3500HD 6.6L Duramax LB7 4WD

Includes:

  • ATS 4WD 2003- Early 2004 Allison LCT1000 Performance Transmission
  • ATS Allison LCT1000 Five Star Torque Converter (302-950-4248)
  • ATS Allison LCT1000 Deep Transmission Pan (301-900-4248)
  • ATS Co-Pilot Transmission Controller (601-924-4248)

Note: $500 Shipping surcharge will be added at checkout

FITMENT GUIDE

Exact Fitment — Verify Your Year

Year RangesYears
Make
Model
Series
Engine
2003-2004
GM/Chevrolet/GMC
Silverado/Sierra
2500HD/3500HD
6.6L Duramax LB7/6.6L Duramax LLY

Document Downloads

Forms & Guides

CUSTOMER REVIEWS

What Buyers Say

Call a Diesel Expert, we'll find the right fit for your build

Not sure this part is right for your truck? Our team knows these platforms inside out. No hold music, no scripts.

Chat with Us