Programmed 2001-2005 Silverado 2500 TCM 15187103 | Allison Transmission Module

Restore Your Allison’s Smooth Shifting

Tired of harsh shifts, limp mode, or a check engine light in your GM HD truck? This Transmission Control Module (TCM) is the solution. It arrives pre-programmed with the latest GM software matched to your VIN, making it a true plug-and-play fix. Skip the expensive dealer programming and get your truck back to working condition fast. Get your truck back to work—order today!

$500.00

+11.99 USPS Priority Shipping

Availability: In stock



SKU: 591-06773-42 Categories: ,
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Restore Peak Performance to Your Allison Transmission

As a technician with over two decades of experience under the hood of heavy-duty trucks, I understand the frustration when a reliable workhorse like your Silverado or Sierra starts acting up. The Allison 1000 series transmission is a legend for its durability, but its electronic brain—the Transmission Control Module (TCM)—can be a point of failure. If you’re dealing with erratic shifting, a truck stuck in limp mode, or a persistent check engine light, you’ve come to the right place for a dependable solution.

This isn’t just a replacement part; it’s a direct-fit, pre-programmed fix. We take the guesswork and the expensive trip to the dealership out of the equation. By providing your vehicle’s VIN at checkout, you receive a TCM loaded with the latest official GM software specific to your truck. This ensures seamless communication between the engine and transmission, restoring the crisp, predictable shifts you depend on. This is the most effective way to solve issues related to a faulty 2001-2005 Silverado 2500 TCM and get your truck back to operating as it should.

From the Diagnostic Bay: The “Limp Mode” Mystery

A customer brought in his ’04 Sierra 3500, a truck he used for his hotshot business. The complaint was intermittent “limp mode”—it would get stuck in 3rd gear, especially after getting hot on a long haul. He’d already replaced a speed sensor with no luck. When I connected my scan tool, I found a U0101 code: Lost Communication with TCM. Instead of just throwing a part at it, I checked the wiring harness near the fan shroud. In my shop, I’ve seen dozens of these harnesses chafe through from engine vibration, causing intermittent shorts. In this case, the harness was perfect. The culprit was internal failure within the original TCM. After installing one of our pre-programmed modules, the communication was solid, the code vanished, and his truck was back on the road earning him money the next day. It’s a classic failure pattern for these vehicles.

Is Your Allison Transmission Acting Up?

A failing TCM can manifest in several ways. If your truck is experiencing any of these issues, a faulty module is the likely cause:

  • ✔ Harsh or erratic shifting
  • ✔ Transmission getting stuck in one gear (Limp Mode)
  • ✔ Delayed engagement into Drive or Reverse
  • ✔ Flashing “Tow/Haul” light
  • ✔ Check Engine Light with transmission-related codes (e.g., P0700, P0751, U0101)
  • ✔ Complete loss of communication with the TCM (no-start or no-shift condition)

A Straightforward Guide to Installation

Replacing the 2001-2005 Silverado 2500 TCM is a job most DIYers can handle with basic tools. Since this module comes pre-programmed to your VIN, no further electronic work is needed.

  1. Safety First: Disconnect the negative terminal from both batteries to prevent any electrical mishaps.
  2. Locate the TCM: On these models, the TCM is conveniently mounted on the driver’s side of the radiator fan shroud.
  3. Disconnect Connectors: Carefully unclip the large electrical connectors from the module. There are typically release tabs that need to be pressed or lifted.
  4. Remove Mounting Bolts: Unbolt the old TCM from the fan shroud. Keep the hardware, as you may need to reuse it.
  5. Install New Module: Mount your new, pre-programmed TCM onto the fan shroud using the original hardware.
  6. Reconnect and Secure: Firmly plug the electrical connectors into the new module until they click into place. Reconnect the battery terminals.
  7. Final Check: Start the truck and allow it to idle. Check for any warning lights and take it for a short test drive to confirm smooth shifting.

Guaranteed Fitment for Your GM HD Truck

This module is a direct replacement for vehicles equipped with the 5-speed Allison automatic transmission (RPO code M74). It is compatible with the following part numbers: 15768288, 15071240, 15163072, 15163073, 15169833, 15169834, 15169835, 15183963, 15187103, 15187104, 29537441, 09385220, and 09387820.

  • Chevrolet Silverado 2500 HD: 2001, 2002, 2003, 2004, 2005
  • Chevrolet Silverado 3500: 2001, 2002, 2003, 2004, 2005
  • GMC Sierra 2500 HD: 2001, 2002, 2003, 2004, 2005
  • GMC Sierra 3500: 2001, 2002, 2003, 2004, 2005

By purchasing this pre-programmed 2001-2005 Silverado 2500 TCM, you are choosing a reliable, hassle-free repair that restores the integrity of your truck’s powertrain.

How does the programming process work?
It’s simple. After you complete your purchase, you provide us with your truck’s 17-digit Vehicle Identification Number (VIN). We use this VIN to load the latest, correct GM software onto the module before we ship it. This makes it a true plug-and-play part for your specific vehicle.
What happens if I don’t provide my VIN?
To ensure you receive a correctly configured part, we cannot ship the module until we receive your VIN. The programming is essential for the TCM to function correctly with your truck’s other systems.
Is this a difficult part to install myself?
Not at all. For most people with basic hand tools, this is a straightforward job that can be done in under an hour. The module is easily accessible on the fan shroud in the engine bay, and no special electronic tools are required since it arrives pre-programmed.
Will this fix my truck going into limp mode?
A faulty TCM is one of the most common causes of a GM truck’s Allison transmission going into limp mode (stuck in 3rd gear). While other issues can cause this, replacing a failed TCM with this programmed unit is a very common and effective solution.
My mechanic quoted me a much higher price. Why?
Dealerships and many repair shops charge for three things: the part itself, the labor to install it, and a separate, often expensive, fee for programming the new module. By ordering this pre-programmed module, you eliminate that separate programming cost entirely.
Genuine OEM

Yes

MPN

15187103

Interchange part number

Condition

Refurbished

PartNumber

591

Model

Silverado 2500 Pickup

Make

Year

2005

Brand

CHEVROLET TRUCK

Manufacturer Part Number

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