If your 2006-2011 Chevrolet Impala is suffering from erratic shifting, getting stuck in gear, or has an illuminated check engine light, you’re likely dealing with a failing Transmission Control Module (TCM). As a technician with over two decades of experience, I’ve seen firsthand how a faulty TCM can make a reliable car feel unpredictable and unsafe. This isn’t just an inconvenience; it’s a critical failure in your vehicle’s nervous system. The TCM is the brain of your automatic transmission, and when it fails, the symptoms can range from annoying to debilitating.
This T42 Transmission Control Module is the definitive solution for your Impala. It arrives expertly programmed to your vehicle’s specific VIN, eliminating the need for expensive and time-consuming dealership visits. This plug-and-play design means you or your mechanic can get your car back to factory-smooth performance quickly. It’s engineered to OEM specifications to restore precise gear changes, proper torque converter engagement, and clear communication between your engine and transmission, solving common diagnostic trouble codes at the source.
Case Study: A Tricky Diagnosis
A customer brought in a 2009 Impala with a complaint that stumped two other shops: intermittent, violent 1-2 shifts, but only after driving for 20 minutes. There were no hard codes, just a generic P0700 (Transmission Control System Malfunction) stored in history. We monitored live data and saw the TCM was commanding the shift solenoids correctly, but the transmission’s response was delayed and harsh. Experience told me this wasn’t a mechanical issue, but an electronic one caused by heat soak. The original TCM’s internal circuits were failing once they reached operating temperature. We installed one of our pre-programmed TCMs, and the problem was solved instantly. The customer saved hundreds, possibly thousands, by avoiding an unnecessary transmission rebuild.
Is Your Impala’s Transmission Showing These Signs?
- ✔ Harsh, delayed, or unpredictable gear shifts.
- ✔ Vehicle is stuck in “limp mode” (usually 2nd or 3rd gear).
- ✔ Check Engine Light is on with transmission-related codes like P0700, P0750, or other solenoid-specific faults.
- ✔ Failure to upshift or downshift, leading to poor acceleration and performance.
- ✔ A noticeable decrease in fuel economy.
- ✔ The gear selector indicator (P-R-N-D) on the dash is blank or incorrect.
A Straightforward Guide to Your Impala TCM Installation
Replacing the 2006-2011 Impala TCM is a job most DIYers can handle in their own garage. For the Impala, the module is conveniently located under the lower air cleaner housing.
- Safety First: Always disconnect the negative terminal from your car’s battery before starting any electronic work.
- Access the Module: Remove the air cleaner assembly to gain clear access to the old TCM.
- Disconnect and Remove: Carefully unplug the electrical connectors. Use a small flathead screwdriver to release the locking tabs if necessary. Then, unbolt the module from its mounting bracket.
- Install the New TCM: Bolt the new, pre-programmed module into place and securely reconnect the electrical harnesses. You should hear a ‘click’ as they lock.
- Final Steps: Reinstall the air cleaner assembly and reconnect the battery terminal. Start the vehicle to confirm the fix. While our programming resolves most issues, it’s good practice to use a basic scan tool to clear any old codes from the vehicle’s memory.
Verified Vehicle Compatibility
This module is a direct-fit replacement for the following vehicles, specifically programmed for your 2006-2011 Impala. It is also compatible with a wide range of other GM vehicles that use the T42 TCM, ensuring broad application and proven reliability.
- Chevrolet Impala (2006-2011) – Located at the lower air cleaner housing.
- Chevrolet Monte Carlo (2006-2007)
- Chevrolet HHR, Cobalt (2006-2011)
- Buick LaCrosse, Allure (2006-2009)
- Pontiac G6, Grand Prix (2006-2010)
- And many more GM models from 2006-2014.
Frequently Asked Questions
Frequently Asked Questions
Do I need to take my car to the dealer after installing this?
No. This Transmission Control Module comes pre-programmed to your car’s VIN. It is a true plug-and-play solution, saving you the time and expense of a dealership visit for programming.
What does this part do?
The TCM is the computer that controls all of your automatic transmission’s functions, including when to shift gears, how firmly to shift, and when to lock the torque converter. A working TCM is essential for performance, driveability, and fuel economy.
Is this a difficult part to install?
For a 2006-2011 Impala, the installation is straightforward. It is located under the air cleaner box and typically takes less than an hour with basic hand tools. Our step-by-step guide can help you through the process.
Will this fix a P0700 trouble code?
A P0700 code indicates a general fault in the transmission control system. In many cases, a failing TCM is the root cause. Replacing your faulty module with this pre-programmed unit is a very common and effective way to resolve a P0700 and other related transmission codes.
What is the warranty on this part?
This module comes with a one-year warranty, giving you peace of mind and confidence in your repair.