Is Your 2006 Envoy XL Shifting Erratically?
If you’re dealing with the frustration of a transmission that won’t shift correctly, bangs into gear, or has left you stranded in limp mode, you’ve come to the right place. As a technician with over two decades of experience, I’ve seen firsthand how a faulty Transmission Control Module (TCM) can mimic a catastrophic transmission failure, causing unnecessary stress and diagnostic headaches. This isn’t just a part; it’s the solution to restore the smooth, predictable performance your GMC was built for. This T42 TCM, part number 24234274, is the brain of your automatic transmission, and we deliver it pre-programmed specifically for your vehicle’s VIN.
A Technician’s Notebook: The Misleading P0700 Code
A customer once brought in a 2007 Silverado with a generic P0700 (Transmission Control System Malfunction) code and a quote for a full transmission rebuild from another shop. The truck was stuck in 3rd gear. Instead of tearing down the transmission, I started with the basics. I checked the TCM connectors for corrosion and then scanned for deeper codes. Sure enough, we had intermittent communication loss codes pointing directly at the T42 module. These modules, exposed to engine bay heat cycles, often develop internal solder joint failures. We swapped in a VIN-programmed TCM, and in under 30 minutes, the truck was shifting perfectly. It’s a prime example of why you should always suspect the TCM before condemning a mechanically sound transmission.
Is Your Vehicle Showing These Telltale Signs?
A failing TCM can cause a range of symptoms. If you’re experiencing any of the following, this module is the likely culprit:
- ✔ Abrupt, harsh, or delayed gear shifts.
- ✔ The vehicle is stuck in a single gear (often called “limp mode”).
- ✔ Check Engine Light or Transmission Warning Light is illuminated.
- ✔ Diagnostic Trouble Codes (DTCs) are present, such as P0700, P0750-P0758 (solenoid codes), or U0101 (Lost Communication with TCM).
- ✔ Failure to upshift or downshift, leading to poor acceleration and fuel economy.
- ✔ Inconsistent or intermittent electrical behavior related to the transmission.
Your 30-Minute Path to a Smooth Ride
One of the best features of this module is its straightforward installation. You don’t need a lift or specialized transmission tools. For most DIYers, this is a job that can be completed in the driveway in less than half an hour.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent electrical shorts and help reset the system.
- Locate the Module: On your 2006 Envoy XL, the TCM is typically found in the left-hand (driver’s side) of the engine compartment. On other GM models, it could be next to the battery, under the air cleaner box, or on a frame rail.
- Disconnect and Remove: Carefully unplug the electrical connectors. Press the release tabs firmly. Then, unbolt the old module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed TCM into place and securely reconnect the electrical harnesses. You should hear a click as they lock in.
- Final Steps: Reconnect the battery terminal. While the module is plug-and-play, it’s always best practice to use a basic OBD2 scan tool to clear any stored fault codes from the vehicle’s memory.
Verified Compatibility for Your GM Vehicle
This T42 TCM is a direct-fit replacement for a wide array of General Motors vehicles equipped with 4-speed automatic transmissions like the 4L60E, 4L65E, and 4L70E. While this page focuses on the 2006 Envoy XL Transmission Module, it also fits the models listed below. It is a direct replacement for part numbers including 24252114, 24234503, 24230461, and more.
ENVOY XL 06 Transmission; (LH engine compartment), (8 cylinder)
TRAILBLAZER 06-07 Transmission; (LH engine compartment), (8 cylinder)
TRAILBLAZER EXT 06 Transmission; (LH engine compartment), (8 cylinder)
CHEVROLET TAHOE 07-09
CHEVROLET SILVERADO 1500 07-13
GMC YUKON 07-09
GMC SIERRA 1500 07-13
CADILLAC DTS 06-11
BUICK LACROSSE 06-09
CHEVROLET IMPALA 06-11
PONTIAC G6 06-10
SATURN AURA 07-09
HUMMER H3 08-10
CHEVROLET COLORADO 08-12
GMC CANYON 08-12
CHEVROLET EXPRESS VAN 06-14
GMC SAVANA VAN 06-14
…and many more models. Please verify fitment using your vehicle’s information.
Frequently Asked Questions
Frequently Asked Questions
What does “VIN Programmed” actually mean?
It means we load your vehicle’s specific Vehicle Identification Number (VIN) and the latest GM software onto the module before we ship it. This ensures it communicates perfectly with your vehicle’s engine computer and other systems right out of the box, eliminating the need for an expensive trip to the dealership for programming.
Do I need any special tools for this installation?
No. Basic hand tools, like a socket set to remove the mounting bolts and potentially a small screwdriver to help with the connector tabs, are all that’s required. The entire process is designed to be DIY-friendly.
Will this fix a P0700 code?
In many cases, yes. A P0700 is a general code indicating a fault has been registered within the TCM. A failing TCM is a very common cause. This module is designed to resolve the internal electronic faults that trigger these codes.
Is there a core charge for my old part?
No, there is no core charge. You can keep your old module or dispose of it without the hassle of sending it back to us.
What kind of warranty is included?
This module is backed by our one-year, hassle-free warranty, giving you confidence and peace of mind in your repair.