Restore Crisp, Reliable Shifting to Your GM Truck
Is your 2007 GMC Sierra 2500 struggling with erratic shifting, getting stuck in gear, or throwing transmission codes? You’re not just dealing with an annoyance; you’re facing a classic symptom of a failing Transmission Control Module (TCM). As a technician with over two decades of experience, I’ve seen countless GM trucks sidelined by this exact issue. The T42 TCM is the electronic brain of your automatic transmission, and when it fails, it can cause drivability problems that range from poor fuel economy to a complete inability to shift. This isn’t just a part—it’s the solution to getting your truck’s performance and reliability back on track.
This replacement T42 module, also known by part number YNXS, is the definitive fix for these widespread problems. We take the guesswork and extra cost out of the repair by pre-programming it to your truck’s specific Vehicle Identification Number (VIN). This means no expensive trip to the dealership for programming. It arrives at your door ready for a true plug-and-play installation, restoring the precise electronic control your transmission needs to function correctly. Don’t let a faulty module compromise your truck’s powertrain; install a dependable, pre-programmed 2007 Sierra 2500 TCM and drive with confidence.
From the Diagnostic Bay
I remember a customer with a 2007 Sierra 2500 work truck that was stuck in ‘limp mode’—third gear only. He’d already replaced two shift solenoids based on the codes, but the problem persisted. His scanner showed a P0700 (Transmission Control System Malfunction). After a quick check of the wiring harness, I suspected the T42 TCM. These modules are notorious for internal circuit board failures due to heat and vibration, leading to intermittent communication loss with the solenoids. We installed one of our VIN-programmed modules, and the truck was shifting perfectly within 30 minutes. He saved a tow to the dealer and a day of lost work.
Is Your Truck Showing These Symptoms?
- âś” Harsh, banging shifts or delayed gear engagement.
- âś” The vehicle is stuck in a single gear (limp mode), often 2nd or 3rd.
- âś” Check Engine Light or Transmission Warning Light is on.
- âś” Diagnostic Trouble Codes (DTCs) are present, such as P0700, P0750, P0753, P0758, or other solenoid-related faults.
- âś” Unexplained loss of fuel efficiency or transmission overheating.
- âś” Complete failure to shift or intermittent loss of communication with the module.
A Straightforward Guide to Your 2007 Sierra 2500 TCM Installation
Replacing the TCM on your Sierra is a job most DIYers can handle in their own driveway in under an hour. On the 2007 Sierra 2500, you’ll typically find it located next to the battery in the engine compartment.
- Safety First: Disconnect the negative terminal from your truck’s battery to prevent any electrical shorts and to help reset the vehicle’s computer systems.
- Locate the Module: Find the TCM, which is a small metal box with electrical connectors, usually mounted on a bracket next to the battery.
- Disconnect and Remove: Carefully unplug the electrical harness connectors. Press the release tabs firmly. Then, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, VIN-programmed TCM into place. Securely reconnect the electrical harnesses, ensuring they click into place.
- Final Steps: Reconnect the negative battery terminal. While the module is plug-and-play, it’s good practice to use a basic OBD2 scanner to clear any stored fault codes from the system. Start the vehicle and test drive to confirm smooth shifting.
Verified Vehicle Compatibility
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, 4L70E, and 4L80E). While this page focuses on the 2007 Sierra 2500 TCM, it also fits the following models. Please verify your specific model and options.
- GMC Sierra 1500/2500 (2007-2013): New body style, typically located next to the battery.
- Chevrolet Silverado 1500/2500 (2007-2013): New body style, also found next to the battery.
- GMC/Chevrolet Savana & Express Vans (2006-2014): Located in the RH engine compartment.
- Chevrolet Tahoe & GMC Yukon (2007-2009): Found next to the battery.
- Chevrolet Colorado & GMC Canyon (2008-2012): Located in the RH rear engine compartment.
- Hummer H3 (2008-2010): Located in the RH rear engine compartment.
- …and many other GM cars, trucks, and SUVs from 2006-2014. A comprehensive list is provided for cross-reference.