Restore Peak Transmission Performance to Your Avalanche
Is your 2007 or 2008 Chevrolet Avalanche 1500 experiencing frustrating transmission issues? Symptoms like harsh, delayed shifting, getting stuck in gear, or an illuminated Check Engine Light can point directly to a failing Transmission Control Module (TCM). The TCM is the electronic brain of your transmission, responsible for orchestrating every gear change and ensuring smooth, efficient operation. When it fails, it can mimic the symptoms of a major mechanical failure, leading to confusion and costly misdiagnoses.
This genuine GM T42 Transmission Control Module, service part number 24241806, is the definitive solution to these problems. We take the guesswork and expense out of the equation by pre-programming the module to your vehicle’s specific VIN before shipping. This means it arrives at your door ready for a simple, plug-and-play installation, completely bypassing the need for a trip to the dealership for expensive programming.
From the Diagnostic Bay
We had a 2008 Silverado come in with classic symptoms: banging into gear and a P0700 code. The owner was convinced he needed a full transmission rebuild, a quote he’d received for thousands of dollars. After connecting our scan tool, we noticed erratic data from the shift solenoids, but the solenoids themselves tested fine. The real culprit was the TCM, which was sending faulty signals. We installed a VIN-programmed T42 module, cleared the codes, and the truck was shifting like new in under an hour. It’s a powerful reminder that diagnosing the electronics first can save you a fortune.
Diagnosing Your 2007-2008 Avalanche 1500 TCM Failure
A failing TCM will often trigger diagnostic trouble codes (DTCs). The most common is a general code like P0700, which simply indicates a fault has been detected within the transmission control system. This is often accompanied by more specific codes related to shift solenoids (e.g., P0751, P0756), pressure control solenoids, or communication errors with the Engine Control Module (ECM). If you’re experiencing the physical symptoms and have these codes, a faulty TCM is the most likely cause. Replacing it with this pre-programmed unit is a direct and effective repair that resolves these electronic issues and restores the precise function of your 4L60E, 4L65E, or 4L70E automatic transmission.
Common Symptoms of a Faulty TCM
- ✔ Harsh or erratic shifting, especially between 1st and 2nd gear.
- ✔ Vehicle gets stuck in “limp mode” (usually 2nd or 3rd gear) to prevent further damage.
- ✔ Check Engine Light or Transmission Warning Light is illuminated on the dash.
- ✔ Delayed engagement when shifting from Park into Drive or Reverse.
- ✔ Complete loss of upshifting or downshifting capabilities.
- ✔ Poor fuel economy due to inefficient gear selection.
- ✔ Inaccurate speedometer readings or other instrument cluster glitches.
Simple Installation, Lasting Results
Designed for a straightforward installation, this module can be swapped out with basic hand tools in under 30 minutes. On the 2007-2008 Avalanche, the TCM is conveniently located in the engine compartment, typically right next to the battery. Simply disconnect the battery, unplug the electrical connectors from the old module, unbolt it, and install the new one in its place. Reconnect everything, and you’re ready to go. Because our module is pre-programmed, your truck’s computer will recognize it immediately, restoring factory shift patterns and performance without any additional steps.
Frequently Asked Questions
What exactly does this T42 TCM do for my Avalanche?
The T42 Transmission Control Module acts as the computer for your automatic transmission. It processes information from sensors throughout the vehicle to control shift points, torque converter lockup, and transmission line pressure, ensuring your truck is always in the correct gear for optimal performance and fuel efficiency.
Is this part really plug-and-play?
Yes. During checkout, we require your vehicle’s VIN. We use this to load the latest GM-certified software specific to your truck onto the module. This ensures it works seamlessly with your engine and other systems right out of the box, with no need for a dealership visit.
Where is the TCM located on my 2007-2008 Avalanche?
On this specific model range, the TCM is typically found in the engine bay, mounted next to the battery. This makes it easily accessible for a quick and simple replacement.
Will this module fix a P0700 trouble code?
A P0700 code is a general fault indicator. While this module often resolves the underlying issue causing the P0700 code (like a failed solenoid driver), it’s important to have the vehicle scanned for any other specific codes (e.g., P0751, P0756) to confirm the TCM is the root cause.
Do I need to send my old part back?
No, there is no core charge for this part. You can keep your old module or dispose of it at your convenience, making the process hassle-free.