If you’re dealing with the frustration of a transmission that won’t shift correctly, you’re not alone. As a technician with over two decades of experience, I’ve seen countless GM vehicles, including the 2006 GMC Envoy XL, come into the shop with jerky shifting, a check engine light, and a driver at their wit’s end. The culprit is often a failed Transmission Control Module (TCM), the electronic brain of your automatic transmission. This T42 TCM, part number 24235340, is the definitive solution to restore your vehicle’s performance and your peace of mind.
This isn’t just a replacement part; it’s a complete, ready-to-install fix. We pre-program the module to your vehicle’s specific VIN before it ships. This means you can skip the expensive and time-consuming trip to a dealership for programming. For the DIY mechanic, this turns a complex electronic repair into a simple bolt-in job. For the professional shop, it means a faster turnaround time and a happier customer.
From the Diagnostic Bay
A customer brought in their ’07 Silverado with the 4L60E, complaining of harsh 1-2 shifts and occasionally getting stuck in third gear (limp mode). The scanner was lighting up with a P0758 for a shift solenoid B electrical fault. After verifying the solenoid’s resistance was good at the transmission connector, we knew the issue was upstream. A quick check of the wiring confirmed the problem was inside the T42 TCM. These modules, exposed to engine bay heat cycles for years, can develop internal breaks in the solenoid driver circuits. We installed one of our VIN-programmed modules, and the truck was shifting like new in less than an hour. This is the exact fix for that common failure pattern.
Why Choose Our Pre-Programmed 2006 Envoy XL TCM?
A failing TCM doesn’t just affect comfort; it impacts fuel economy, vehicle safety, and can lead to more severe transmission damage if ignored. Our module directly addresses the root causes of common T42 failures, providing a reliable and lasting repair. It manages everything from shift points and line pressure to torque converter lockup, ensuring your transmission operates exactly as the factory intended.
Is Your Envoy XL Exhibiting These Transmission Faults?
- ✔ Harsh, erratic, or delayed gear shifts.
- ✔ Vehicle is stuck in a single gear (often called “limp mode”).
- ✔ Check Engine Light or Transmission Warning Light is on.
- ✔ Diagnostic Trouble Codes (DTCs) are present, such as P0700, P0751, P0753, P0756, or other solenoid-related faults.
- ✔ Failure to upshift or downshift, resulting in poor acceleration.
- ✔ Noticeable decrease in fuel efficiency.
A Straightforward Guide to Installation
- ✔ Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent electrical shorts and reset the system.
- ✔ Locate the Module: On the 2006 Envoy XL, the TCM is typically found in the left-hand (driver’s side) of the engine compartment.
- ✔ Disconnect and Remove: Carefully unplug the electrical connectors from the old TCM. Then, unbolt the module from its mounting bracket.
- ✔ Install the New Module: Bolt the new, pre-programmed TCM into place. Reconnect the electrical connectors, ensuring they click securely.
- ✔ Final Steps: Reconnect the battery terminal. While our programming handles the critical setup, it’s good practice to use a basic scan tool to clear any stored fault codes from other modules. Start the vehicle and test drive to confirm smooth shifting.
Verified Vehicle Compatibility
This module, also known by service numbers 24242391, 24234503, and 24252114, is a direct replacement for a wide range of GM vehicles. While this page is focused on the 2006 Envoy XL TCM, it also fits models like the Chevrolet Silverado, Tahoe, Impala; GMC Sierra, Yukon; Cadillac DTS, and many more equipped with 4-speed automatic transmissions (4L60E, 4L65E, 4L70E). Please see the detailed fitment list below to confirm compatibility.
Frequently Asked Questions
Do I need to take this part to a dealer for programming?
No. This Transmission Control Module comes fully pre-programmed to your vehicle’s VIN. It is ready for installation right out of the box, saving you time and money.
What is a TCM and what does it do?
The TCM, or Transmission Control Module, is a computer that controls your vehicle’s automatic transmission. It reads data from various sensors to manage gear shifting, fluid pressure, and torque converter operation for optimal performance and fuel economy.
Is this a difficult part to install myself?
For most DIYers with basic hand tools, this is a straightforward installation. The module is located in the engine bay and is typically accessible. The entire process can often be completed in under 30 minutes.
Will this fix a P0700 trouble code?
A P0700 code is a general fault request from the TCM to the main engine computer (ECM) to turn on the Check Engine Light. While this module will resolve the underlying transmission issue that *caused* the P0700 code (like a bad solenoid circuit), you will still need to clear the code with a scan tool after installation.
Is there a core charge for my old part?
No, we do not require a core return. You can keep your old part, making the transaction simple and hassle-free.