Restore Your Envoy’s Shifting Performance
Is your 2006-2009 GMC Envoy suffering from harsh shifting, getting stuck in gear, or displaying a check engine light with transmission codes? These are classic signs of a failing Transmission Control Module (TCM). The TCM is the electronic brain of your automatic transmission, responsible for orchestrating every gear change, managing torque converter lockup, and ensuring smooth, efficient operation. When it fails, it can leave your vehicle unreliable and frustrating to drive. This genuine GM T42 TCM, service number 24240449, is the definitive solution to restore your vehicle’s factory performance and dependability.
From the Diagnostic Bay
We had a 2008 GMC Envoy come into the shop stuck in what the owner called “get home mode.” The transmission wouldn’t shift past 3rd gear, and the check engine light was on with a P0700 code. After checking the basics, we scanned the TCM and found multiple solenoid circuit faults. Instead of a costly transmission rebuild, we identified the root cause: a faulty internal processor in the original TCM. We installed one of our VIN-programmed T42 modules. The installation took less than 30 minutes. After clearing the codes, the Envoy shifted perfectly on the test drive, saving the customer thousands and getting them back on the road with confidence.
Why Choose Our Pre-Programmed Envoy Transmission Control Module?
Replacing a modern electronic component like a TCM isn’t just about swapping parts. The module must be electronically matched to your specific vehicle. Our service eliminates the most difficult step: programming. We flash this module with your vehicle’s unique Vehicle Identification Number (VIN) and the latest GM software updates before it ships. This means it arrives ready for a true plug-and-play installation. You avoid expensive dealership programming fees and the hassle of towing your vehicle. This is the most efficient and reliable way to fix your transmission issues correctly the first time.
Common Symptoms of a Failing TCM
- ✔ Harsh, erratic, or delayed gear shifts.
- ✔ Vehicle stuck in limp mode (often 2nd or 3rd gear).
- ✔ Check Engine Light or Transmission Warning Light is illuminated.
- ✔ Diagnostic Trouble Codes (DTCs) such as P0700, P0750, P0753, P0758, or other solenoid-related faults.
- ✔ Inability to upshift or downshift properly.
- ✔ Noticeable decrease in fuel economy.
- ✔ Intermittent loss of communication with the TCM.
Simple Installation, Lasting Results
For the 2006-2009 GMC Envoy, this module is typically located in the left-hand (driver’s side) engine compartment, making it easily accessible. The replacement process is straightforward for a DIY mechanic or any professional technician. Simply disconnect the battery, unplug the electrical connectors from the old module, unbolt it, and install the new one. Reconnect everything, and you’re ready to go. Because it’s pre-programmed, your Envoy will recognize the new module immediately. We recommend clearing any old codes with a standard OBD2 scanner after installation to complete the process. With no core charge, you don’t have to worry about the hassle and expense of returning your old part.
Frequently Asked Questions
What does a Transmission Control Module do in my GMC Envoy?
The TCM acts as the central computer for your automatic transmission. It receives data from various sensors (like vehicle speed, engine RPM, and throttle position) to determine the perfect moment to shift gears, control fluid pressure, and engage the torque converter clutch for optimal performance and fuel efficiency.
Is this TCM really plug-and-play?
Yes. We pre-program the module using your vehicle’s VIN before shipping. This ensures it has the correct software and calibration for your specific Envoy, eliminating the need for any additional programming from a dealership. It arrives ready to be installed and function correctly.
Where is the TCM located on a 2006-2009 GMC Envoy?
On the 2006-2009 GMC Envoy, the Transmission Control Module is typically found in the engine compartment on the driver’s side (LH side). Always confirm the location on your specific vehicle before beginning the replacement.
What happens if I don’t replace a failing TCM?
Ignoring a failing TCM can lead to more severe issues. Continued harsh shifting can cause premature wear on internal transmission components like clutches and bands, potentially leading to a complete transmission failure that is far more expensive to fix. It can also leave you stranded if the vehicle enters limp mode permanently.
Will this part fit other GM vehicles?
Yes, this T42 TCM is compatible with a wide range of General Motors vehicles from 2006-2014, including models like the Chevrolet Silverado, Tahoe, GMC Sierra, Buick LaCrosse, and more. Please check the detailed fitment list on our product page to confirm compatibility with your specific vehicle.