If you’re dealing with erratic shifting, a check engine light, or your 2020-2021 Silverado 3500 has gone into limp mode, a failing Transmission Control Module (TCM) is often the culprit. This critical component is the brain of your automatic transmission, responsible for controlling shift points, torque converter lockup, and fluid pressure. When it fails, it can make your powerful truck feel unreliable and unsafe. This isn’t just an inconvenience; it’s a problem that needs a direct and dependable solution.
We offer a straightforward fix: a genuine replacement TCM (service part number 24289415) that arrives at your door fully programmed to your truck’s specific Vehicle Identification Number (VIN). By handling the programming before we ship, we eliminate the most frustrating part of the repair—no expensive trips to the dealership, no need for specialized scan tools, and no extra programming fees. This is the most efficient way to restore your transmission’s performance and get your truck back to work.
Case Study: A Tricky Diagnosis
I had a 2020 Sierra 2500 in the bay last month with a classic complaint: intermittent harsh 2-3 shifts and occasional ‘Service Transmission’ warnings on the dash. The owner had already replaced the fluid and filter, but the problem persisted. Scans revealed a U0100 (Lost Communication with TCM) code that would pop up randomly. After checking the wiring harness and connectors for integrity—a crucial first step—we isolated the issue to the TCM itself. These modules can suffer from internal logic failures that don’t always throw a hard fault immediately. We installed one of our pre-programmed modules, and after the quick relearn procedure, the truck was shifting smoother than ever. The customer saved hundreds compared to the dealer quote and was back on the road in an afternoon.
Is Your Truck Showing These Symptoms?
A faulty TCM can manifest in several ways. If you’re experiencing any of the following, this module is the likely solution for your 2020-2021 Silverado 3500 TCM issues:
- ✔ Harsh, erratic, or delayed gear shifting.
- ✔ Vehicle stuck in one gear (limp mode).
- ✔ Check Engine Light is illuminated.
- ✔ Common Diagnostic Trouble Codes (DTCs) like P0700, P0751, or U0100.
- ✔ Inaccurate gear display on the instrument cluster.
- ✔ Poor fuel economy due to inefficient shifting.
A Straightforward Guide to Installation
Installing your new TCM is a manageable job for a DIYer with basic tools. This pre-programmed module makes the process much simpler. While specific steps may vary slightly, here is a general guide for a Silverado/Sierra HD truck.
- Safety First: Disconnect the negative terminal from your truck’s battery to prevent any electrical shorts.
- Locate the TCM: On most late-model GM trucks, the TCM is mounted on the driver’s side (LH) core support, near the front of the engine bay.
- Disconnect Connectors: Carefully unclip the electrical wiring harnesses from the old module. Use a small flathead screwdriver to gently release the locking tabs if necessary.
- Remove Mounting Bolts: Unbolt the old TCM from its mounting bracket. Keep the hardware, as you will reuse it.
- Install the New TCM: Mount your new, pre-programmed TCM onto the bracket and secure it with the original bolts.
- Reconnect Everything: Firmly plug the electrical connectors into the new module. You should hear a ‘click’ as they lock into place. Reconnect the negative battery terminal.
- Perform Relearn (Recommended): While the truck will run, a transmission relearn procedure with a capable scan tool is recommended to ensure the smoothest possible shifts as the system adapts to the new module.
Verified Vehicle Compatibility
This module, part number 24289415, is a direct replacement for service numbers 24042698, 24043411, 24043413, and 24296206. It is guaranteed to fit the following vehicles:
- CAMARO 2022-2023 (Underhood, LH frame rail)
- SIERRA 1500 PICKUP 2019 (New style, mirrors on door skin)
- SIERRA 1500 PICKUP 2020
- SIERRA 2500 PICKUP 2020-2022
- SIERRA 3500 PICKUP 2020-2022
- SIERRA DENALI 1500 2019-2020
- SIERRA DENALI 2500 2020-2022
- SIERRA DENALI 3500 2020-2022
- SILVERADO 1500 PICKUP 2019 (New style, mirrors on door skin)
- SILVERADO 1500 PICKUP 2020
- SILVERADO 2500 PICKUP 2020-2021
- SILVERADO 3500 PICKUP 2020-2021
Restoring your truck’s shifting performance is simple. Provide your VIN at checkout, and we’ll handle the complex programming. Order your 2020-2021 Silverado 3500 TCM today and experience the difference of a properly functioning transmission.
Frequently Asked Questions
Do I need to get this part programmed by a dealer?
No. We program the module to your vehicle’s VIN before shipping it. This means it’s ready for installation right out of the box, saving you time and money.
What information do you need from me?
After you place your order, you must provide us with your 17-digit Vehicle Identification Number (VIN). This is essential for us to load the correct GM software for your truck’s specific configuration.
Is this a difficult part to install myself?
For someone with basic mechanical skills, this is a very manageable installation. The TCM is typically easy to access in the engine bay, requiring only simple hand tools to swap out.
Will this fix my ‘limp mode’ problem?
In the vast majority of cases where limp mode is caused by a TCM-related fault code (like U0100 or P0700), replacing the module with this pre-programmed unit will resolve the issue.
What if I have a different service number?
This part (24289415) is the correct and updated service replacement for several older part numbers, including 24042698, 24043411, 24043413, and 24296206. If your old module has one of these numbers, this is the correct part for you.