Restore Your Envoy’s Shifting Performance
If you’re dealing with the headaches of a failing transmission control module in your 2006-2009 GMC Envoy, you know how frustrating it can be. One minute your SUV is driving fine, the next it’s slamming into gear, refusing to shift, or stuck in limp mode. As a technician with over two decades of experience, I’ve seen countless GM vehicles sidelined by these exact issues. The Transmission Control Module (TCM), specifically the T42 model, is the brain of your automatic transmission, and when it fails, it can mimic a catastrophic transmission failure, causing unnecessary stress and diagnostic confusion.
This is not just a replacement part; it’s a complete solution. We offer this high-quality 2006-2009 Envoy TCM pre-programmed to your vehicle’s specific VIN. This crucial step eliminates the need for expensive dealership visits for programming. You get a module that is ready for installation right out of the box, loaded with the latest GM software updates to ensure optimal communication between your engine and transmission. It’s the most reliable and efficient way to get your Envoy back on the road, shifting smoothly and dependably.
From the Diagnostic Bay
I remember a 2008 Envoy that came into my shop with a classic case of intermittent transmission chaos. The owner was convinced he needed a full transmission rebuild. It would drive perfectly for days, then suddenly start shifting harshly and throw a P0700 code. After checking the fluid and wiring, we hooked up our high-end scanner and monitored the TCM data. We saw erratic commands being sent to the shift solenoids, a tell-tale sign of internal module failure. Instead of a multi-thousand-dollar rebuild, the fix was a new, VIN-programmed TCM. The customer was back on the road in under an hour for a fraction of the cost, with his Envoy shifting better than it had in years.
Is Your Envoy Exhibiting These Transmission Faults?
A faulty TCM can manifest in several ways. If you’re experiencing any of the following, your module is the likely culprit. Early diagnosis can save you from further transmission damage.
- ✔ Harsh, erratic, or delayed gear shifts.
- ✔ Vehicle is stuck in one gear (often called ‘limp mode’).
- ✔ Check Engine Light or Transmission Warning Light is illuminated.
- ✔ Diagnostic Trouble Codes (DTCs) stored, such as P0700, P0750, or other solenoid-related faults.
- ✔ Complete loss of upshifting or downshifting capabilities.
- ✔ A noticeable decrease in fuel economy.
- ✔ The torque converter fails to lock up, leading to higher RPMs at cruising speed.
Your Straightforward Installation Guide
Replacing the 2006-2009 Envoy TCM is a job most DIYers can handle in their own driveway in about 30 minutes. The module is conveniently located in the engine bay, making access simple.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts and to help reset the system.
- Locate the Module: On the GMC Envoy, the TCM is typically found in the left-hand (driver’s side) of the engine compartment.
- Disconnect and Remove: Carefully unplug the electrical connectors. Press the release tabs firmly. Then, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, VIN-programmed TCM into place. Securely reconnect the electrical harnesses, ensuring they click into place.
- Final Steps: Reconnect the battery terminal. While our programming handles the critical setup, it’s good practice to use a basic OBD2 scan tool to clear any lingering fault codes from the vehicle’s memory.
Verified Fitment for Your General Motors Vehicle
This T42 Transmission Control Module is a direct replacement for part number 24239224 and is interchangeable with many other service numbers. It is compatible with a wide array of GM vehicles equipped with 4-speed automatic transmissions like the 4L60E and 4L65E. Please verify your vehicle is on the list below.
- GMC ENVOY: 2006-2007 (8 cylinder, LH engine compartment), 2008-2009 (LH engine compartment)
- Chevrolet TRAILBLAZER: 2006-2007 (8 cylinder, LH engine compartment), 2008-2009 (LH engine compartment)
- Chevrolet SILVERADO 1500: 2007-2013 (next to battery)
- GMC SIERRA 1500: 2007-2013 (next to battery)
- Chevrolet TAHOE: 2007-2009 (next to battery)
- GMC YUKON: 2007-2009 (next to battery)
- …and many more models from Buick, Cadillac, Hummer, Pontiac, Saab, and Saturn.
Frequently Asked Questions
What exactly does a Transmission Control Module (TCM) do?
The TCM is a computer that acts as the ‘brain’ for your automatic transmission. It collects data from various sensors on the vehicle (like vehicle speed and engine RPM) and uses that information to control when the transmission shifts gears, when the torque converter locks up, and overall transmission performance for a smooth and efficient ride.
Do I really not need to program this module?
That’s correct. We handle the programming for you before we ship the part. By providing your vehicle’s VIN during checkout, we flash the module with the specific software for your Envoy, making it a true plug-and-play solution. This saves you a trip to the dealership and the associated programming fees.
Where is the TCM located on my 2007 GMC Envoy?
On the 2006-2009 GMC Envoy, the TCM is located in the engine bay, on the left-hand (driver’s side). Its accessible location makes for a quick and easy replacement.
My old module has a different part number on it. Will this still work?
Yes, most likely. GM uses many different part numbers for the same component over the years. This module, 24239224, is a service replacement for a long list of other part numbers, including 24252114, 24234503, 24230461, and more. As long as your vehicle is on our compatibility list, this module will function correctly.
Is there a core charge for this part?
No, we do not require a core charge. You can keep your old part, so there’s no need to worry about the hassle and expense of shipping it back to us.