Restore Flawless Shifting to Your Pontiac Grand Prix
Is your 2006, 2007, or 2008 Pontiac Grand Prix suffering from harsh shifts, getting stuck in gear, or throwing transmission codes? A faulty Transmission Control Module (TCM) is one of the most common culprits behind these frustrating and potentially damaging issues. As the electronic brain of your automatic transmission, the TCM dictates every gear change. When it fails, drivability suffers. This replacement T42 TCM, part number 24230461, is the definitive solution, arriving pre-programmed to your vehicle’s specific VIN for a true plug-and-play repair.
A Technician’s Notebook: The Grand Prix That Wouldn’t Cooperate
I had a 2007 Grand Prix roll into my bay last month with the classic symptoms. The owner was frustrated, describing how the car would slam into gear from a stop and sometimes refuse to shift past 2nd gear—classic limp mode. A quick scan showed a P0700 (Transmission Control System Malfunction) and a handful of solenoid circuit codes. While some might jump to rebuilding the transmission, my experience pointed straight to the electronics. The original TCM was failing intermittently. We installed one of our VIN-programmed modules, and the difference was immediate. All codes cleared, and the car shifted as smoothly as it did from the factory. The customer saved thousands by avoiding an unnecessary transmission teardown.
Is Your Grand Prix Showing These Telltale Signs?
A failing TCM doesn’t heal itself; the symptoms only get worse. If you’re experiencing any of the following, it’s time for a replacement. This module is the solution for your 2006-2008 Grand Prix TCM problems.
- âś” Abrupt, harsh, or jerky gear shifts.
- âś” The vehicle is stuck in a single gear (limp mode).
- âś” Check Engine Light is on with codes like P0700, P0750, or other transmission-related DTCs.
- âś” Delayed engagement when shifting from Park to Drive or Reverse.
- âś” Complete failure to shift up or down.
- âś” Poor fuel economy and a feeling of lost power.
- âś” Intermittent loss of communication with the transmission module.
A Straightforward Guide to Installation
One of the best features of this module is its simple installation. For the Pontiac Grand Prix, the process is accessible for any DIY enthusiast. You can have your car back to normal in under an hour.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electronic work.
- Locate the TCM: On your 2006-2008 Grand Prix, the TCM is typically found mounted to the lower air cleaner housing in the engine bay. It’s a silver box with electrical connectors.
- Disconnect and Remove: Carefully unplug the electrical harnesses from the old module. Then, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, VIN-programmed TCM into place and securely reconnect the electrical harnesses. Ensure they click into place.
- Reconnect and Verify: Reconnect the battery terminal. Start the vehicle and let it idle for a moment. Use a basic OBD2 scan tool to clear any lingering fault codes from the ECU.
- Test Drive: Take the car for a short drive to confirm that shifting is smooth and all warning lights are off.
Verified Vehicle Compatibility
This T42 Transmission Control Module is a direct replacement for part number 24230461 and is interchangeable with a wide range of other GM service numbers, including 24252114, 24234503, 24234274, and more. While this page focuses on the 2006-2008 Grand Prix TCM, it also fits the following vehicles (please verify location based on your specific model):
- Pontiac Grand Prix: 2006-2008 (lower air cleaner housing)
- Chevrolet Impala: 2006-2011 (lower air cleaner housing)
- Chevrolet Monte Carlo: 2006-2007 (lower air cleaner housing)
- Buick Allure: 2006-2009 (lower air cleaner housing)
- Buick LaCrosse: 2006-2009 (lower air cleaner housing)
- Chevrolet Silverado / GMC Sierra: 2007-2013 (next to battery)
- Chevrolet Tahoe / GMC Yukon: 2007-2009 (next to battery)
- Chevrolet Cobalt / Pontiac G5 / Saturn Ion: 2006-2010 (LH strut tower)
- And many more GM models from 2006-2014.