Restore Flawless Shifting in Your Heavy-Duty Truck
Is your 2015 or 2016 GMC Sierra 3500 experiencing delayed shifts, shuddering, or a frustrating check engine light? These are classic signs of a failing Transmission Control Module (TCM). The TCM is the electronic brain of your transmission, and when it malfunctions, it can cripple your truck’s performance and reliability. This genuine GM module, part number 24276411, is the definitive solution. We take the guesswork and dealership hassle out of the equation by pre-programming it with the latest GM software, specifically matched to your truck’s Vehicle Identification Number (VIN). This ensures it works perfectly right out of the box, restoring the crisp, predictable shifting you depend on, especially when towing heavy loads.
Signs Your Transmission Control Module is Failing
A faulty TCM can manifest in several ways, often starting subtly and getting progressively worse. If you’re noticing any of the issues below, it’s a strong indication that your module needs attention. Ignoring these symptoms can lead to further transmission wear and more costly repairs down the line.
- ✔ Erratic or harsh gear changes
- ✔ Vehicle getting stuck in one gear (limp mode)
- ✔ “Service Transmission” or similar warning on the dash
- ✔ Check Engine Light with codes like P0700, P0751, or U0101
- ✔ Delayed engagement when shifting from Park to Drive or Reverse
- ✔ Poor fuel economy due to inefficient shifting
Step-by-Step Guide to a Proper Installation
Replacing the 2015-2016 Sierra 3500 TCM is a straightforward job that can be done with basic hand tools. Since we handle the programming, you can avoid a trip to the dealership. Follow these steps for a smooth installation.
- Safety First: Disconnect the negative terminal from your truck’s battery to prevent any electrical shorts.
- Locate the TCM: On the Sierra HD models, the TCM is typically mounted on the driver’s side of the fan shroud in the engine bay.
- Disconnect Wiring: Carefully release the locking tabs on the electrical connectors and unplug them from the old module. Inspect the connectors for any corrosion or damage.
- Remove the Old Module: Unbolt the old TCM from its mounting bracket on the fan shroud. It’s usually held in place by a few small bolts.
- Install the New Module: Mount your new, pre-programmed TCM onto the bracket and secure it. Reconnect the electrical harnesses, ensuring they click securely into place.
- Reconnect Power: Reattach the negative battery terminal and tighten it.
- Final Check: Start the vehicle and let it idle for a moment. Take it for a short test drive to allow the transmission to adapt to the new module. Shifting should feel immediately improved.
A Mechanic’s Field Tale: The Tow Rig’s Redemption
A customer brought in his ’16 Sierra 3500, a dually he used to haul a massive fifth-wheel trailer. He was complaining of terrifyingly hard downshifts when coming down mountain passes. The truck would slam into gear, jolting the entire rig. We pulled a U0101 code—lost communication with the TCM. Instead of a multi-day dealership stay, we ordered one of these pre-programmed modules. The next day, it was a 15-minute swap in the parking lot. The customer called later that week from the road, ecstatic that his truck drove better than it had in years. That’s the power of getting the right part, programmed correctly from the start.
Compatibility Check: Does It Fit Your Vehicle?
This module is a direct-fit replacement for a wide range of GM trucks and SUVs. Please verify your vehicle is on the list below. This is the correct 2015-2016 Sierra 3500 TCM for models with the 6-speed automatic transmission (RPO code MW7).
- Cadillac Escalade/ESV: 2015-2017 (8-speed, M5U)
- Chevrolet Camaro: 2016
- Chevrolet Silverado 1500: 2015-2016 (8-speed, M5U)
- Chevrolet Silverado 2500/3500: 2015-2016 (6-speed, MW7)
- GMC Sierra 1500 / Denali 1500: 2015-2016 (8-speed, M5U)
- GMC Sierra 2500/3500 & Denali 2500/3500: 2015-2016 (6-speed, MW7)
- GMC Yukon / Yukon XL: 2015-2016 (8-speed, M5U)
- Cadillac CTS: 2016 (with ID 24276411)
Note: After purchase, please provide your VIN so we can flash the module with the correct software for your specific vehicle configuration.
Frequently Asked Questions
Do I need to program this module?
No. We handle all the programming for you before shipment. Simply provide us with your vehicle’s VIN during checkout, and we will load the latest GM-certified software onto the module. It will arrive ready for installation.
Where is the TCM located on my 2016 Sierra 3500?
For the 2015-2016 Sierra 2500/3500 and Silverado 2500/3500 models, the Transmission Control Module is located on the driver’s side (LH) of the fan shroud inside the engine compartment.
What is a VIN and where do I find it?
VIN stands for Vehicle Identification Number. It’s a unique 17-digit code for your truck. You can find it on the driver’s side of the dashboard (visible through the windshield), on the driver’s side door jamb sticker, or on your vehicle’s registration and insurance documents.
Will this part fix my transmission problem for sure?
This module will correct issues directly caused by a faulty TCM, such as communication errors, false sensor readings from the module, and software glitches. However, it will not fix pre-existing mechanical problems within the transmission, such as a worn clutch or a bad solenoid. A proper diagnosis is always recommended.
Is any other procedure needed after I install it?
In most cases, no further steps are required. The pre-programming ensures it communicates correctly with your truck’s other systems. A short drive cycle of mixed city and highway driving can help the system fully adapt to the new module.