Restore Peak Performance to Your GM Heavy-Duty Truck
The Allison 1000 5-speed transmission in your 2001-2005 Sierra or Silverado HD is a legendary workhorse, known for its durability and strength. However, the brain of this powerful transmission, the Transmission Control Module (TCM), can be a point of failure over time. When your TCM begins to malfunction, it can lead to a host of frustrating and potentially damaging issues, from unpredictable shifting to the dreaded “limp mode.” This replacement TCM, part number 15768288, is the definitive solution to restore the crisp, reliable shifting your truck was built for.
This isn’t just a replacement part; it’s a complete, ready-to-install solution. We take the guesswork and extra expense out of the equation by programming the module specifically to your truck’s Vehicle Identification Number (VIN) before it ships. This ensures seamless communication with your truck’s other systems, like the Engine Control Module (ECM), and loads the latest GM-certified software for optimal performance and longevity. You get a direct-fit part that works correctly right out of the box, with no need for an expensive trip to the dealership for programming.
From the Diagnostic Bay
We had a 2004 Silverado 2500HD come into the shop that the owner used for his landscaping business. His complaint was that the truck would randomly slam into gear and occasionally get stuck in 3rd gear (limp mode), especially when towing his equipment trailer. He’d already replaced sensors to no avail. We scanned the vehicle and found a U0101 code—Lost Communication with TCM. After checking the wiring harness and connectors for integrity, we pinpointed the internal failure of the module itself. We installed one of our VIN-programmed TCMs, cleared the codes, and took it for a test drive. The shifting was immediately smooth and decisive, both loaded and unloaded. The customer was back on the road the same day, saving hundreds in diagnostic time and dealer programming fees.
Is Your Truck Showing Signs of a Failing TCM?
A faulty Allison Transmission Control Module can manifest in several ways. If you’re experiencing any of the following symptoms, a failing TCM is the likely culprit:
- ✔ Harsh, erratic, or delayed shifting.
- ✔ The transmission getting stuck in one gear (limp mode).
- ✔ Check Engine Light is on with transmission-related codes (like P0700, P07xx series, or U0101).
- ✔ The gear indicator on the dash displays incorrectly or not at all.
- ✔ Complete loss of power or inability to move.
- ✔ A scan tool cannot communicate with the TCM.
The Plug-and-Play Advantage
Replacing a modern electronic module can be a complicated process. Our goal is to make it as simple as possible. By providing us with your VIN during checkout, you empower our technicians to flash the module with the precise software configuration for your vehicle’s specific options and build. This critical step ensures that the new TCM integrates perfectly, restoring the original factory performance and shift patterns. The module is located on the driver’s side (LH) of the fan shroud, making it accessible for a straightforward installation.
Guaranteed Compatibility
This module is a direct replacement for a wide range of original service numbers, ensuring broad compatibility for your heavy-duty truck. It is designed for all 2001-2005 Sierra 2500/3500 and Silverado 2500/3500 models equipped with the 5-speed Allison 1000 automatic transmission (RPO code M74).
Compatible Service Numbers: 15768288, 15071240, 15163072, 15163073, 15169833, 15169834, 15169835, 15183963, 15187103, 15187104, 29537441, 09385220, 09387820
Frequently Asked Questions
How do I provide my vehicle’s VIN?
You can add your 17-digit VIN in the notes section during checkout. If you forget, we will contact you via email after your purchase to request it. We cannot ship the module until we have programmed it.
Is any additional programming or a “relearn” procedure required after installation?
No. Because we program the unit with the latest software using your VIN, it is ready for immediate installation and operation. No dealer tools or relearn procedures are necessary.
Where is this TCM located on my truck?
The Transmission Control Module on 2001-2005 GM HD trucks is typically mounted on the driver’s side of the radiator fan shroud in the engine bay for cooling.
Will this fix my truck’s “limp mode” problem?
If a faulty TCM has been properly diagnosed as the cause of your transmission issues, including limp mode or erratic shifting, this part is the correct solution to resolve the problem.
Is this compatible with both 2WD and 4WD models?
Yes, the programming we perform using your VIN accounts for all of your vehicle’s specific options, including the drivetrain, ensuring it works correctly for your exact configuration.