Restore Smooth, Reliable Shifting to Your Pontiac Grand Prix
If you’re dealing with the headaches of a failing transmission—erratic shifting, a car stuck in limp mode, or a persistent check engine light—you know how frustrating it can be. As a technician with over two decades of experience, I’ve seen countless GM vehicles, including the Pontiac Grand Prix, sidelined by a faulty Transmission Control Module (TCM). The TCM is the brain of your automatic transmission, and when it starts to fail, it can cause a cascade of problems that make your car feel unreliable and unsafe. This isn’t just an annoyance; it’s a critical failure that impacts performance, fuel economy, and drivability.
This OEM-quality T42 TCM is the definitive solution for your 2006-2008 Grand Prix TCM issues. We take the guesswork and high dealership costs out of the equation. Each module is professionally programmed to your vehicle’s specific VIN before it ships, ensuring it’s a true plug-and-play part. You get a reliable fix that restores the precise, smooth shifting you expect from your car, without needing expensive scan tools or a trip to the service center for programming.
A Technician’s Notebook: The Intermittent Shifting Nightmare
I once had a 2007 Grand Prix in the bay that was a real head-scratcher. The owner complained of random, violent shifts, but only after the car was fully warmed up. It would drive perfectly for 20 minutes, then suddenly slam into gear. No consistent codes were stored, just a generic P0700 (Transmission Control System Malfunction) every now and then. After checking wiring and solenoids, we focused on the TCM. Heat soak was causing an internal fault in the module. We swapped it with a VIN-programmed unit, and the problem vanished instantly. It’s a classic failure mode for these modules, where thermal stress leads to unpredictable behavior that can be tough to diagnose without seeing it firsthand.
Is Your Grand Prix Showing These Transmission Warning Signs?
A failing TCM will give you clear signals. If you’re experiencing any of the following, it’s highly likely your module needs replacement. Ignoring these symptoms can lead to more severe transmission damage down the road.
- ✔ Harsh, jerky, or delayed gear shifts.
- ✔ The vehicle is stuck in one gear (often called “limp mode”).
- ✔ Check Engine Light or Transmission Warning Light is on.
- ✔ Diagnostic Trouble Codes (DTCs) are present, such as P0700, P0750, P0753, P0758, or other solenoid-related faults.
- ✔ Inability to upshift or downshift properly.
- ✔ A noticeable drop in fuel efficiency.
- ✔ The transmission feels like it’s slipping between gears.
Your Straightforward Installation Guide
One of the best features of this part is its simple installation, which a confident DIYer can complete in under 30 minutes. For the 2006-2008 Pontiac Grand Prix, you’ll find the TCM located under the lower air cleaner housing.
- Safety First: Disconnect the negative terminal from your car’s battery to prevent any electrical shorts and to help reset the system.
- Locate the Module: Access the area beneath the air cleaner box in the engine compartment to find the old TCM.
- Disconnect and Remove: Carefully unplug the electrical connectors from the module. Then, unbolt the module from its mounting bracket and remove it from the vehicle.
- Install the New TCM: Mount your new, pre-programmed TCM in the same location and securely fasten it. Reconnect the electrical connectors, ensuring they click into place.
- Final Steps: Reconnect the 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 ECU. Start the car and enjoy your smooth-shifting transmission!
Verified Vehicle Compatibility
This module, part number 24235754, is the correct replacement for the specified models. While it is guaranteed to fit the 2006-2008 Grand Prix TCM application, it is also interchangeable with a wide range of other GM vehicles that use the T42 controller. Always verify your part number or contact us with your VIN to ensure perfect fitment.
- Pontiac Grand Prix (2006-2008): Transmission; (lower air cleaner housing)
- This part also fits numerous other GM models, including Chevrolet Impala, Buick LaCrosse, GMC Envoy, and more. Please refer to the full fitment list or contact our experts.
Do I need to have this TCM programmed by a dealer?
Do I need to have this TCM programmed by a dealer?
No. We program the module to your vehicle’s VIN before shipping. It arrives ready for plug-and-play installation, saving you the time and expense of a dealership visit.
Is this a new or used part?
This is a high-quality, OEM-standard replacement part that has been expertly prepared and programmed for your vehicle. It is backed by our one-year warranty for your peace of mind.
What if I order the wrong part?
We strongly encourage you to provide your VIN at checkout to guarantee compatibility. If you have any doubts, our expert support team is here to help you verify the correct part for your Grand Prix before you order.
Is there a core charge for my old TCM?
No, there is no core charge required for this module. You can keep your old part, making the replacement process simple and hassle-free.