If your 2006 GMC Envoy XL is giving you headaches with unpredictable shifting, getting stuck in gear, or a persistent check engine light, you’ve likely pinpointed a faulty Transmission Control Module (TCM). As the central computer for your automatic transmission, a failing TCM can make your reliable SUV feel unsafe and unpredictable. This isn’t just an annoyance; it’s a critical failure that impacts drivability and fuel economy. I’ve seen countless GM vehicles in my shop with these exact issues, and replacing the TCM is the definitive, lasting solution.
This T42 series TCM is a direct-fit replacement for your vehicle, engineered to meet or exceed original equipment specifications. The most significant benefit is our professional VIN programming service. We flash the module with your vehicle’s specific VIN and the latest GM software updates before it ships. This means it arrives at your door ready for a true plug-and-play installation, saving you the time, hassle, and high cost of a dealership visit for programming. Restore the crisp, smooth shifting performance your Envoy XL had when it was new with this reliable, pre-programmed module.
A Technician’s Notebook
A customer brought in a 2006 Envoy XL with the 8-cylinder engine, complaining it was stuck in what felt like third gear (limp mode) and the transmission warning light was on. A quick scan pulled a P0700 (Transmission Control System Malfunction) and a P0753 (Shift Solenoid ‘A’ Electrical). While the P0753 points to a solenoid, my experience with these T42 modules immediately made me suspect the TCM itself. The internal drivers for the solenoids are a common failure point. Instead of starting a costly internal transmission repair, we opted to replace the TCM first. With this pre-programmed unit, the swap took less than 20 minutes in the driver’s side engine bay. After clearing the codes, the Envoy shifted perfectly on the test drive. The customer saved hundreds, possibly thousands, by avoiding an unnecessary transmission teardown.
Is Your Envoy XL Showing These Symptoms?
A failing TCM will give you clear warning signs. If you’re experiencing any of the following, it’s time to consider a replacement:
- ✔ Harsh, slamming shifts or delayed gear engagement.
- ✔ Vehicle is stuck in a single gear (often called “limp mode”).
- ✔ Check Engine Light is on with transmission-related Diagnostic Trouble Codes (DTCs), such as P0700, P0750, P0755, etc.
- ✔ Inability to upshift or downshift, leading to poor acceleration.
- ✔ A noticeable drop in fuel efficiency.
- ✔ The transmission seems to slip out of gear unexpectedly.
A Straightforward Guide to Installation
For the 2006 GMC Envoy XL, this is a repair most DIYers can handle with basic tools in their own driveway. The module is easily accessible.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the Module: On your Envoy XL, the TCM is found in the engine compartment on the left-hand (driver’s) side.
- Disconnect and Remove: Carefully unplug the electrical connectors. Press the release tabs firmly to avoid damaging them. Then, unbolt the old module from its mounting bracket.
- Install the New TCM: Mount the new, pre-programmed module in place and tighten the bolts. Reconnect the electrical harnesses, ensuring they click securely into place.
- Final Steps: Reconnect the battery terminal. While the module is plug-and-play, it’s good practice to use a basic OBD2 scan tool to clear any stored fault codes from the vehicle’s memory. Start the vehicle and enjoy restored performance.
Verified Vehicle Compatibility
This module is a direct replacement for part number 24235753 and is interchangeable with many other T42 TCMs. It fits the following models, among others. Please verify your specific application.
- GMC Envoy XL (8 cylinder): 2006
- Chevrolet Silverado & GMC Sierra 1500/2500: 2007-2013
- Chevrolet Tahoe & GMC Yukon: 2007-2009
- Chevrolet Express & GMC Savana Vans: 2006-2014
- Cadillac DTS: 2006-2011
- Buick LaCrosse / Lucerne: 2006-2011
- Pontiac G6 / Grand Prix: 2006-2010
- Chevrolet Impala / Monte Carlo: 2006-2011
- Chevrolet HHR / Cobalt: 2006-2011
- Saturn Vue / Aura / Ion: 2006-2010
- Hummer H3: 2008-2010
- Saab 9-7X: 2006-2009
Frequently Asked Questions
Do I need to program this module after I receive it?
No. The main benefit of our service is that we program the module to your vehicle’s specific VIN before shipping. It is ready for installation right out of the box, with no dealership visit required.
Where is the TCM located on my 2006 Envoy XL?
On the 2006 GMC Envoy XL with the 8-cylinder engine, the Transmission Control Module is located in the engine compartment on the left-hand (driver’s) side.
Will this fix a P0700 trouble code?
A P0700 code is a general fault request from the TCM to the main engine computer. In a vast majority of cases I’ve diagnosed on these GM platforms, replacing a faulty TCM resolves the P0700 code and any accompanying solenoid or sensor codes (like P0753, P0758, etc.).
What kind of warranty is included?
This part comes with a one-year replacement warranty, giving you peace of mind and confidence in your repair.
Is there a core charge for my old part?
No, there is no core charge. You can keep your old part, which simplifies the process and saves you the hassle and cost of return shipping.