End Your Tahoe’s Transmission Headaches for Good
If you’re dealing with a 2007-2009 Chevrolet Tahoe that’s shifting harshly, getting stuck in gear, or throwing transmission codes, you know how frustrating it can be. As a technician with over two decades of experience, I’ve seen countless GM trucks and SUVs sidelined by a faulty Transmission Control Module (TCM). The T42 module is the electronic brain of your automatic transmission, and when it fails, it can mimic a major mechanical problem. This VIN-programmed T42 TCM, part number 24240400, is the direct, reliable solution to restore your vehicle’s performance and peace of mind without a costly trip to the dealership for programming.
From the Diagnostic Bay: The Case of the Limp-Mode Tahoe
A customer brought in his ’08 Tahoe, explaining it felt like it was “slamming into gear” and was stuck in what felt like 3rd gear (limp mode). The check engine light was on, and his code reader showed a P0700 (Transmission Control System Malfunction) and a P0752 (Shift Solenoid A Stuck On). He was worried he needed a full transmission rebuild. After a quick check of the fluid and connections, I suspected the TCM. These modules are known to fail internally, causing erratic solenoid commands. We installed one of our pre-programmed T42 modules, and in less than an hour, the Tahoe was shifting as smoothly as it did from the factory. It’s a common scenario, and this part is the proven fix.
Is Your Tahoe Exhibiting These Transmission Faults?
A failing TCM can cause a variety of symptoms that are often misdiagnosed. Before you suspect a major mechanical failure, see if your vehicle is showing these classic signs of a bad 2007-2009 Tahoe TCM:
- âś” Harsh, erratic, or delayed gear shifts that slam or jerk the vehicle.
- âś” The vehicle is stuck in a single gear (often called “limp mode”) and will not upshift or downshift.
- âś” Check Engine Light or Transmission Warning Light is illuminated on the dashboard.
- âś” Diagnostic Trouble Codes (DTCs) are present, such as P0700, P0750-P0758, or other solenoid-related faults.
- âś” A noticeable decrease in fuel economy due to inefficient shifting.
- âś” The torque converter fails to lock up at highway speeds, causing high RPMs.
DIY-Friendly Installation: Get Back on the Road Fast
One of the biggest benefits of this module is the simple, straightforward installation. Because we program it to your vehicle’s VIN before shipping, you don’t need any special dealer tools. For most 2007-2009 Tahoes, the process takes less than 30 minutes.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts and to help reset the vehicle’s computer systems.
- Locate the TCM: On your Tahoe, the TCM is typically mounted in the engine bay, right next to the battery. It’s a silver box with large electrical connectors.
- Disconnect and Remove: Carefully unclip the wiring harnesses from the old module. Then, unbolt the module from its mounting bracket. There are usually just a few bolts holding it in place.
- Install the New Module: Bolt the new VIN-programmed TCM into the same location. Securely reconnect the wiring harnesses, ensuring they click 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 transmission codes. Start the vehicle and take it for a test drive to confirm the smooth shifting.
Verified Compatibility for Your GM Vehicle
This T42 Transmission Control Module is a direct replacement for part number 24240400 and is interchangeable with a wide range of other service numbers. It is designed for GM vehicles equipped with 4-speed automatic transmissions like the 4L60E, 4L65E, and 4L70E. While this page focuses on the 2007-2009 Tahoe TCM, this part also fits many other models. Please verify your specific model in the list below:
Fits Models Including:
TAHOE 07-09: Transmission; (next to battery), check for auxiliary oil cooler pump option.
SILVERADO 1500 PICKUP 07-13: Transmission; (next to battery), check for new body style and hybrid options.
YUKON / YUKON XL 1500 07-09: Transmission; (next to battery).
AVALANCHE 1500 07-08: Transmission; (next to battery).
SAVANA / EXPRESS VANS 06-14: Transmission; (RH engine compartment).
…and many other GM cars, trucks, and SUVs from 2006-2014.
Frequently Asked Questions
Do I need to take my vehicle to the dealer for programming?
No. This Transmission Control Module is delivered to you pre-programmed to your vehicle’s specific VIN. This makes it a true plug-and-play solution, saving you time and money.
Where is the TCM located on my 2008 Tahoe?
On the 2007-2009 Chevrolet Tahoe and GMC Yukon, the TCM is typically found in the engine compartment, mounted on a bracket right next to the battery.
Will this fix a P0700 trouble code?
A P0700 code is a general fault code indicating the TCM has detected a problem. While this module often resolves the root cause (like a faulty solenoid circuit within the TCM itself), you should ensure there are no external wiring or sensor issues. In most cases I’ve seen, replacing the TCM clears the P0700 and related codes.
Is a core charge required for my old part?
No, there is no core charge. You can keep your old module without the hassle of returning it.
What is the warranty on this part?
This part comes with a one-year warranty, giving you confidence in its quality and reliability for your daily driver or work truck.