Restore Peak Transmission Performance in Your GM Truck
If your 2007 GMC Sierra 2500 is suffering from harsh shifts, getting stuck in gear, or throwing transmission codes, the culprit is often a failing Transmission Control Module (TCM). As the electronic brain of your automatic transmission, a faulty TCM can cripple your truck’s performance and reliability. I’ve seen it countless times in my 20 years on the shop floor: a perfectly good mechanical transmission is sidelined by a bad module. This T42 Transmission Control Module, part number 24255280, is the definitive solution, arriving pre-programmed to your vehicle’s specific VIN for a true plug-and-play fix.
Forget about expensive dealership visits and the hassle of programming. We handle the technical work for you. By flashing this module with the latest GM software updates tied directly to your VIN, we ensure it communicates flawlessly with your truck’s engine computer (ECM) and other systems right out of the box. This restores precise shift points, proper torque converter lockup, and accurate diagnostic reporting, effectively resolving common issues and preventing further transmission damage. This is the same reliable fix I’d use on a customer’s vehicle to get them back on the road with confidence.
From the Diagnostic Bay: The “Limp Mode” Sierra
A customer brought in a 2007 Sierra 2500 work truck that was stuck in what he called “get-home gear.” The transmission wouldn’t shift past 3rd, the check engine light was on, and his fuel economy had plummeted. A quick scan showed a P0700 (Transmission Control System Malfunction) and a few solenoid circuit codes. While the codes pointed to the solenoids, my experience with these T42 modules told me to look at the controller first. We swapped in one of our VIN-programmed TCMs, cleared the codes, and took it for a test drive. The truck shifted like it was new again. The original solenoids were fine; the module was simply failing to command them correctly. This simple swap saved the customer from an unnecessary and costly internal transmission repair.
Is Your Sierra Exhibiting These Transmission Faults?
A failing TCM can manifest in several ways, often mistaken for more severe mechanical problems. Before you consider a full transmission replacement, check if your truck is showing these common signs of a bad 2007 Sierra 2500 TCM.
- âś” Harsh, slamming shifts or erratic gear changes.
- âś” Vehicle stuck in “limp mode,” typically only allowing 2nd or 3rd gear.
- âś” Check Engine Light or Transmission Warning Light illuminated on the dash.
- âś” Diagnostic Trouble Codes (DTCs) stored, such as P0700, P0750-P0758, or other solenoid-related faults.
- âś” Delayed engagement when shifting from Park to Drive or Reverse.
- âś” Complete loss of upshifting or downshifting capabilities.
- âś” Noticeably poor fuel efficiency and potential for transmission overheating.
A Straightforward 30-Minute Installation
One of the best features of this module is its ease of installation. For most DIYers with basic tools, this is a job you can complete in your own driveway in under 30 minutes. The specific location of your 2007 Sierra 2500 TCM is next to the battery in the engine compartment.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work. This prevents short circuits and helps reset the vehicle’s computer systems.
- Locate the Module: On your Sierra 2500, you’ll find the TCM mounted right next to the battery. It’s a silver box with several large electrical connectors.
- Disconnect and Remove: Carefully unplug the electrical harnesses from the old TCM. Then, unbolt the module from its mounting bracket and remove it from the vehicle.
- Install the New Module: Mount your new, pre-programmed TCM onto the bracket and securely plug in the electrical connectors. You’ll hear a click as they lock into place.
- Reconnect and Verify: Reconnect the negative battery terminal. Start the engine and check for any warning lights. While our programming resolves most codes, it’s good practice to use a basic OBD-II scanner to clear any lingering fault codes from the system’s memory.
Verified Compatibility for Your GM Vehicle
This T42 TCM is a direct replacement for a wide range of General Motors vehicles equipped with 4-speed automatic transmissions like the 4L60E, 4L65E, and 4L80E. It is an exact match for part number 24255280 and interchanges with several other service numbers, including 24252114, 24234503, and 24239224. While this page focuses on the 2007 Sierra 2500 TCM, this part also fits the following models (please verify location notes):
- GMC Sierra/Chevrolet Silverado 1500/2500 (2007-2013): Located next to the battery.
- GMC Savana/Chevrolet Express Vans (2006-2014): Found in the RH engine compartment.
- Chevrolet Tahoe/GMC Yukon (2007-2009): Located next to the battery.
- Chevrolet Colorado/GMC Canyon (2008-2012): Found in the RH rear engine compartment.
- Hummer H3 (2008-2010): Located in the RH rear engine compartment.
- Chevrolet Impala/Buick LaCrosse (2006-2011): Typically under the lower air cleaner housing.
- …and many other GM cars, trucks, and SUVs from 2006-2014.
Do I need to take this part to a dealer for programming?
Do I need to take this part to a dealer for programming?
No. This Transmission Control Module comes fully pre-programmed to your vehicle’s specific VIN. This is a plug-and-play solution that requires no additional dealership programming, saving you time and money.
Will this fix a P0700 trouble code?
A P0700 code is a general fault code indicating the TCM has detected a problem. In many cases where the TCM itself is the root cause of other transmission codes, replacing it with our programmed module will resolve the P0700 and related codes.
Where is the TCM located on my 2007 Sierra 2500?
For the 2007 GMC Sierra 2500 (new body style), the TCM is conveniently located in the engine bay, right next to the battery. This makes for a very accessible and quick replacement.
Is there a core charge for this part?
No, there is absolutely no core charge. You are not required to send your old, faulty module back to us, which simplifies the process for you.
What kind of warranty is included?
We stand behind our parts with a one-year warranty, giving you peace of mind that you’re installing a quality, reliable component in your truck.