Is your 2006-2009 GMC Envoy suffering from erratic shifting, getting stuck in gear, or displaying a check engine light? These are classic signs of a failing Transmission Control Module (TCM). The TCM is the electronic brain of your automatic transmission, responsible for orchestrating smooth gear changes and ensuring optimal performance. When it fails, it can lead to frustrating and potentially damaging driving conditions. This genuine quality GM T42 TCM, service number 24235754, is the definitive solution, pre-programmed to your vehicle’s specific VIN for a true plug-and-play installation.
From the Diagnostic Bay
We had a 2008 GMC Envoy come into the shop last month that was stuck in what the owner called ‘permanent third gear.’ No matter what, it wouldn’t upshift or downshift, and the transmission warning light was on. A quick scan showed a P0700 code, pointing to a general transmission fault. After checking the basics, we pinpointed the TCM. Instead of a costly trip to the dealer for a new module and programming, we installed one of these VIN-programmed units. After a 20-minute installation and clearing the codes, the Envoy was shifting perfectly again. The customer saved hundreds and was back on the road the same day.
Is Your Envoy Showing Signs of a Failing TCM?
A faulty TCM can manifest in various ways, often starting as intermittent issues before becoming a constant problem. If you’re experiencing any of the following symptoms, your transmission control module is the likely culprit:
- ✔ Harsh, delayed, or erratic gear shifts that make driving uncomfortable.
- ✔ The vehicle enters “limp mode,” often getting stuck in 2nd or 3rd gear.
- ✔ An illuminated Check Engine Light or Transmission Warning Light on your dashboard.
- ✔ Diagnostic Trouble Codes (DTCs) such as P0700, P0750, or other solenoid-related faults.
- ✔ A complete failure to shift up or down, leading to poor acceleration and fuel economy.
- ✔ The transmission seems to slip out of gear or has trouble engaging Drive or Reverse.
Why Choose Our Programmed Envoy Transmission Control Module?
This isn’t just a replacement part; it’s a complete, ready-to-install solution designed to restore your vehicle’s factory performance. The most critical feature is our VIN programming service. We flash the module with the latest GM software updates specific to your vehicle’s Vehicle Identification Number before it ships. This eliminates the need for expensive dealership programming or specialized scan tools, making the installation process straightforward for both DIY mechanics and professional technicians. This T42 module directly controls shift solenoids, torque converter lockup, and line pressure, ensuring your 4L60E, 4L65E, or 4L70E transmission operates precisely as the manufacturer intended.
Built to meet and exceed original equipment standards, this module ensures long-term reliability. It is a direct replacement for a wide range of part numbers, including 24252114, 24234503, 24230461, 24235754, and more, guaranteeing compatibility and function. With a one-year warranty and no core charge, you can complete your repair with confidence and without the hassle of returning your old part.
Simple Installation to Get You Back on the Road
Replacing the TCM is a manageable job for most home mechanics. On the GMC Envoy and related platforms like the Trailblazer and Saab 9-7X, the module is typically located in the engine compartment on the driver’s side. On other GM vehicles, it can be found next to the battery, under the air cleaner box, or on a frame rail. The process is simple:
- Disconnect the Battery: Always disconnect the negative battery terminal first to prevent electrical damage and help reset the vehicle’s systems.
- Locate and Remove the Old TCM: Unplug the electrical connectors and unbolt the old module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed TCM in place and securely reconnect the wiring harnesses.
- Reconnect the Battery: Reattach the negative battery terminal.
- Clear Codes: Use a standard OBD2 scan tool to clear any stored transmission codes. Start the vehicle and test drive to confirm the issue is resolved.
Broad GM Vehicle Compatibility
While this is the perfect solution for your 2006-2009 Envoy, this T42 TCM is also compatible with a vast array of other GM cars, trucks, and SUVs equipped with 4-speed automatic transmissions. Popular models include the Chevrolet Silverado, Tahoe, Suburban, Impala, and Cobalt; GMC Sierra, Yukon, and Savana; Buick LaCrosse and Lucerne; Cadillac DTS; Pontiac G6; and Hummer H3, among many others. Please verify the part number or use our vehicle fitment tool to ensure compatibility.
Frequently Asked Questions
What does a Transmission Control Module (TCM) do?
The TCM is a computer that receives data from various sensors on the engine and transmission. It uses this information to control electronic shift solenoids, regulate fluid pressure, and determine the optimal gear for any driving condition, ensuring smooth performance and fuel efficiency.
Why is VIN programming so important for this part?
VIN programming loads your vehicle’s specific software and calibrations onto the module. Without it, the TCM won’t communicate correctly with your vehicle’s other computers, leading to continued shifting problems or a no-start condition. Our pre-programming service makes it a plug-and-play part, saving you a trip to the dealership.
Will this fix a P0700 trouble code?
A P0700 code is a general fault code indicating that the TCM has detected a problem and has requested the Check Engine Light to be turned on. While a faulty TCM is a very common cause, this code can also be triggered by other transmission issues. However, if you are experiencing shifting symptoms along with a P0700, replacing the TCM is the most probable fix.
Is this TCM difficult to install?
For most individuals with basic mechanical skills and tools, the installation is straightforward and typically takes less than 30 minutes. The module is usually in an accessible location in the engine bay. Since our module comes pre-programmed, there are no complex software procedures required.
Do I need to send my old part back?
No, there is no core charge for this part. You can keep your old module, which simplifies the process and saves you the time and expense of return shipping.