Restore Smooth Shifting to Your Pontiac Grand Prix
If you’re dealing with the frustration of a 2006-2008 Pontiac Grand Prix that shifts harshly, gets stuck in gear, or has a persistent check engine light, you’ve likely pinpointed the problem: a failing Transmission Control Module (TCM). As the electronic brain of your automatic transmission, a faulty TCM can cause a cascade of issues that make your car unreliable and unpleasant to drive. This T42 series TCM, part number 24241806, is the definitive solution, arriving expertly programmed to your vehicle’s VIN for a hassle-free, plug-and-play installation.
A Technician’s Notebook: The Intermittent Shifting Nightmare
I remember a 2007 Grand Prix that came into the shop with a complaint that stumped two other mechanics. The owner described random, violent shifts and occasional limp mode, but the problem would disappear for days at a time. Diagnostic codes were inconsistent. After checking the wiring and solenoids, everything seemed fine. From experience, I know that heat and vibration, especially on a module mounted near the engine, can cause microscopic cracks in the TCM’s circuit board. These cracks create intermittent connection failures that don’t always throw a clear code. We installed a VIN-programmed TCM, and the problem was solved instantly. This isn’t just about replacing a part; it’s about installing a reliable component that won’t leave you guessing.
Is Your Grand Prix Showing These Transmission Warning Signs?
A failing TCM doesn’t heal itself; the symptoms only get worse. Ignoring them can lead to more significant transmission damage. Here’s what to look for:
- âś” Abrupt, harsh, or delayed gear changes.
- âś” The vehicle is stuck in a single gear (often called “limp mode”).
- âś” Check Engine Light or Transmission Warning Light is on, with Diagnostic Trouble Codes (DTCs) like P0700, P0750, or other solenoid-related faults.
- âś” Failure to upshift or downshift, leading to poor acceleration and terrible fuel economy.
- âś” A complete loss of communication with the transmission.
Your Straightforward Installation Guide
For the 2006-2008 Pontiac Grand Prix, this is a job most DIYers can handle in their own driveway in under 30 minutes. No specialized tools are needed.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electronic work.
- Locate the Module: On your Grand Prix, the TCM is conveniently located under the lower air cleaner housing. You will need to remove the airbox to access it.
- Disconnect and Remove: Carefully unclip the wiring harness connectors from the old TCM. Then, unbolt the module from its mounting bracket.
- Install the New TCM: Mount your new, pre-programmed TCM in place of the old one and securely reconnect the wiring harnesses. You’ll hear a ‘click’ when they’re properly seated.
- Final Steps: Reinstall the air cleaner housing and reconnect the battery. While the module is plug-and-play, it’s good practice to use a basic scan tool to clear any stored fault codes from the vehicle’s memory.
By choosing our pre-programmed 2006-2008 Grand Prix TCM, you are bypassing the expensive and time-consuming trip to a dealership for programming. This module is ready to work the moment you install it, restoring the crisp, predictable shifting your car had when it was new.
Verified Compatibility for Your Vehicle
This T42 Transmission Control Module is a direct-fit replacement for the 2006-2008 Grand Prix and is also compatible with a wide range of other GM vehicles. Please verify your model and part number for a guaranteed fit.
Partial Fitment List:
- GRAND PRIX 06-08 Transmission; (lower air cleaner housing)
- IMPALA 06-11 Transmission; (lower air cleaner housing)
- LACROSSE 06-09 Transmission; (lower air cleaner housing)
- MONTE CARLO 06-07 Transmission; (lower air cleaner housing)
- COBALT 06-10 Transmission; (LH strut tower)
- G6 06-10 Transmission; (LH strut tower)
- HHR 06-11 Transmission; (LH engine compartment)
- MALIBU 06-10 Transmission; (LH frame rail)
- And many more GM models…
What is the main benefit of a VIN-programmed TCM?
What is the main benefit of a VIN-programmed TCM?
VIN programming ensures the module is loaded with the correct software and calibrations specifically for your Grand Prix’s transmission, engine, and options. This makes it a true plug-and-play part, eliminating the need for an expensive dealership visit to program a blank module.
Can I install this 2006-2008 Grand Prix TCM myself?
Absolutely. The installation is straightforward, typically taking less than 30 minutes with basic hand tools. Its location under the air cleaner housing is accessible for most DIY enthusiasts.
Will this part fix a P0700 trouble code?
A P0700 code is a general fault request from the TCM to the main computer. While this module often resolves the underlying cause (like a solenoid circuit fault), you should always diagnose the specific codes the TCM has stored. In many cases, replacing a faulty TCM is the correct fix.
Is there a core charge for my old part?
No, there is no core charge required. You can keep or dispose of your old module without the hassle of returning it, saving you time and money.