Restore Your Pontiac’s Performance with a Reliable Transmission Fix
If your 2006-2008 Pontiac Grand Prix is suffering from harsh, erratic shifting, getting stuck in gear, or throwing transmission-related check engine lights, you’re not just dealing with an annoyance—you’re facing a critical component failure. As a technician with over two decades of experience, I’ve seen countless drivers worry that their entire transmission is shot. More often than not, the real culprit is a faulty Transmission Control Module (TCM). This VIN-programmed T42 TCM, part number 24241806, is the definitive solution to get your Grand Prix driving smoothly and reliably again, without the excessive cost and hassle of a dealership visit.
This isn’t just a replacement part; it’s a direct-fit, pre-programmed fix engineered to restore your vehicle’s factory performance. The TCM is the brain of your automatic transmission, controlling everything from shift points to torque converter clutch engagement. When it fails, the symptoms can be dramatic and concerning. Our module solves these issues at their source, ensuring your transmission receives the correct commands for seamless operation and optimal fuel efficiency.
From the Diagnostic Bay: A Common Grand Prix Scenario
A customer brought in his ’07 Grand Prix, complaining it would slam into gear and was stuck in what felt like 3rd gear (limp mode). He was convinced he needed a full transmission rebuild, a quote he’d gotten for thousands of dollars elsewhere. I scanned the vehicle and pulled a P0700 (Transmission Control System Malfunction) and a few solenoid circuit codes. Instead of tearing down the transmission, my first step was to inspect the TCM. These T42 modules are known to fail internally over time, causing precisely these symptoms. We installed one of our VIN-programmed modules, and in under an hour, the car was shifting perfectly. He saved a fortune by correctly diagnosing the electronic failure instead of assuming a mechanical one.
Is Your Grand Prix Showing These Signs?
A failing TCM can manifest in several ways. If you’re experiencing any of the following, this module is the likely solution for your 2006-2008 Grand Prix TCM issues:
- ✔ Harsh, banging shifts or delayed gear engagement.
- ✔ Vehicle is stuck in “limp mode” and won’t shift out of a single gear.
- ✔ The check engine light or transmission warning light is on.
- ✔ Diagnostic Trouble Codes (DTCs) are present, especially P0700, P0750, or other solenoid-related faults.
- ✔ A sudden drop in fuel economy or a feeling of sluggish performance.
- ✔ Complete loss of communication with the transmission module.
DIY-Friendly Installation: Get Back on the Road Fast
One of the biggest advantages of this part is its ease of installation. Because we program it to your VIN before shipping, it’s a true plug-and-play component. For the 2006-2008 Pontiac Grand Prix, the process is particularly straightforward.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the TCM: On your Grand Prix, the transmission control module is conveniently located inside the lower air cleaner housing in the engine bay.
- Access the Module: Remove the air cleaner assembly to gain clear access to the old TCM.
- Disconnect and Remove: Carefully unplug the electrical connectors from the old module and unbolt it from its mounting position.
- Install the New Module: Bolt the new, pre-programmed TCM into place and securely reconnect the electrical harnesses. You should hear a ‘click’ as they lock in.
- Reassemble and Test: Reinstall the air cleaner housing, reconnect the battery, and start the vehicle. It’s a good practice to use a basic scan tool to clear any stored codes after the repair.
Verified Vehicle Compatibility
This T42 TCM is a direct replacement for part number 24241806 and other interchangeable numbers. While it is guaranteed to fit the 2006-2008 Pontiac Grand Prix, it also fits a wide range of other GM vehicles. Please see the detailed list below to confirm fitment for other models. If your vehicle is a Grand Prix from 2006-2008, this is the correct part for you.
GRAND PRIX 06-08 Transmission; (lower air cleaner housing)
… and other compatible vehicles such as Impala, LaCrosse, Monte Carlo, etc.
Do I need to take my car to the dealer for programming?
Do I need to take my car to the dealer for programming?
No. This is the biggest benefit of our service. We pre-program the module to your vehicle’s specific VIN before we ship it. This makes the installation plug-and-play, saving you time and the high cost of dealership programming.
What information do you need from me?
We require your 17-digit Vehicle Identification Number (VIN) at checkout. This allows us to load the correct GM factory software for your specific vehicle, ensuring perfect compatibility and performance.
Will this fix a P0700 check engine light code?
In many cases, yes. The P0700 code is a general fault code indicating the TCM has detected a problem. If the TCM itself is the source of the failure, replacing it with our programmed module will resolve the issue and allow you to clear the code.
Is this a difficult part for a DIY mechanic to install?
Not at all. For the Pontiac Grand Prix, the module is located under the air filter box, making it one of the easier TCMs to access. With basic hand tools, most DIYers can complete the job in under 30-45 minutes.
Is there a core charge for my old part?
No, we do not require you to send back your old module. There is no core charge, which simplifies the process for you.