Is your 2006-2010 Pontiac G6 suffering from frustrating transmission problems? If you’re dealing with harsh shifting, getting stuck in gear, or seeing a check engine light that points to the transmission, you’ve likely pinpointed the culprit: a failing Transmission Control Module (TCM). As a mechanic with over two decades of experience, I’ve seen countless GM vehicles, including the G6, sidelined by a faulty T42 TCM. This isn’t just an annoyance; it’s a critical component failure that affects your car’s drivability and safety.
This replacement T42 TCM, part number 24235753, is the definitive solution. We take the guesswork and extra cost out of the repair by programming the module to your vehicle’s specific VIN before it ships. This means it arrives at your door ready for a true plug-and-play installation, restoring the precise, smooth shifting your G6 had from the factory. You can finally solve those persistent transmission codes and get your car back to being reliable transportation.
A Technician’s Notebook
A customer brought in a 2009 Pontiac G6 with a classic complaint: ‘It drives fine for 15 minutes, then it starts banging into gear and the check engine light comes on.’ They’d already replaced a shift solenoid with no luck. After hooking up my scan tool, I saw the tell-tale P0700 (Transmission Control System Malfunction) and some intermittent solenoid circuit codes. The data stream showed the TCM was commanding shifts, but the feedback was erratic after it warmed up. This is a common failure pattern for these T42 modules. Heat exposure causes internal circuits to fail over time. We installed a VIN-programmed TCM, cleared the codes, and the car shifted perfectly on a long test drive. It’s a textbook fix for a very common problem.
Is Your Pontiac G6 Showing These Warning Signs?
- ✔ Abrupt, jerky gear changes or a noticeable slam when shifting.
- ✔ The vehicle refuses to shift out of a single gear (often called ‘limp mode’).
- ✔ An illuminated Check Engine Light or Transmission Warning Light on your dash.
- ✔ Diagnostic Trouble Codes (DTCs) such as P0700, P0750, or other transmission-related faults.
- ✔ Delayed engagement when shifting from Park to Drive or Reverse.
- ✔ A significant and unexplained drop in fuel economy.
DIY-Friendly Installation: Get Back on the Road Fast
Replacing the 2006-2010 G6 TCM is a straightforward job that most DIYers can handle in their own garage in under an hour. For the Pontiac G6, the module is conveniently located on the LH (driver’s side) strut tower in the engine bay.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the TCM: Open the hood and find the module mounted to the driver’s side strut tower. It’s a silver box with electrical connectors.
- Disconnect and Remove: Carefully unclip the wiring harnesses from the old TCM. Then, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed TCM into place and securely reconnect the wiring harnesses. Ensure they click into place.
- Final Steps: Reconnect the battery terminal. While the module is pre-programmed, it’s always a good practice to use a basic OBD-II scan tool to clear any stored fault codes from the vehicle’s memory.
Verified Vehicle Compatibility
This T42 TCM is a direct-fit replacement for a wide range of General Motors vehicles. While this page focuses on the 2006-2010 G6 TCM, it is also compatible with the following models. Please verify your specific model and location notes.
- Pontiac G6 (2006-2010): Transmission; (LH strut tower)
- Chevrolet Cobalt (2006-2010): Transmission; (LH strut tower)
- Chevrolet HHR (2006-2011): Transmission; (LH engine compartment)
- Chevrolet Impala (2006-2011): Transmission; (lower air cleaner housing)
- Chevrolet Malibu (2006-2010): Transmission; (LH frame rail)
- Saturn Aura (2007-2009): Transmission; (LH frame rail front)
- Saturn Ion (2006-2007): Transmission; (behind LH strut tower)
- And many more GM models from 2006-2014. This module interchanges with part numbers 24242391, 24234503, 24252114, 24235753, and others.
Frequently Asked Questions
What does ‘VIN Programmed’ actually mean?
It means we load your vehicle’s unique 17-digit Vehicle Identification Number (VIN) and the latest GM-approved software onto the module before we ship it. This ensures it communicates perfectly with your car’s other computers right out of the box, eliminating the need for an expensive programming session at a dealership.
Do I need any special tools for this installation?
No special tools are required. Basic hand tools like a socket set to remove the mounting bolts and a small screwdriver to help release the connector clips are all you should need. The most important part is providing your VIN at checkout.
Will this fix a P0700 trouble code?
A P0700 code is a generic code indicating the TCM has detected a fault. Often, when the TCM itself is the source of the problem, replacing it will resolve the P0700 and any related specific codes (like for solenoids or sensors). It is the most common fix for this code when accompanied by shifting issues.
Is there a core charge for my old part?
No, there is no core charge. You can keep your old module or dispose of it yourself, saving you the time and hassle of shipping a part back.
How can I be sure this is the part I need?
If your Pontiac G6 is experiencing the symptoms listed, such as erratic shifting, limp mode, or transmission-related codes, a failed TCM is the most probable cause. Verifying the part number (24235753 or an interchange) on your original module is the best way to confirm a match.