Regain Control of Your Tahoe’s Transmission
If you’re dealing with the frustration of a 2007-2009 Chevrolet Tahoe that shifts harshly, gets stuck in gear, or throws transmission-related check engine lights, you’ve likely pinpointed the culprit: a failing Transmission Control Module (TCM). As a technician with over two decades of experience, I’ve seen countless GM trucks and SUVs sidelined by this exact issue. This isn’t just an annoyance; it’s a critical failure that can leave you stranded. This OEM-quality T42 TCM, part number 24239224, is the definitive, hassle-free solution. It arrives pre-programmed to your vehicle’s specific VIN, eliminating the need for expensive dealership visits and getting you back on the road with confidence.
Case Study: A Tricky Diagnosis
A customer brought in his ’08 Tahoe complaining of intermittent ‘slam shifting’ between 1st and 2nd gear and occasionally getting stuck in 3rd (limp mode), but only after it had been running for over an hour. The check engine light would come and go, showing a generic P0700 code. We checked fluid levels and solenoids, which all tested fine cold. The issue was heat-related breakdown within the original TCM. After swapping in a pre-programmed module like this one, the problem was solved permanently. The pre-programming ensured the new module communicated perfectly with the ECU and BCM from the moment it was installed, saving the customer hundreds in diagnostic and programming fees at the dealer.
Is Your Tahoe Exhibiting These Transmission Problems?
A faulty TCM can manifest in several ways. If you’re experiencing any of the following, it’s a strong indicator that your module needs replacement. Over the years, I’ve found these are the most common symptoms for a failing 2007-2009 Tahoe TCM.
- ✔ Harsh, slamming, or erratic gear shifts.
- ✔ Vehicle is stuck in a single gear (often called ‘limp mode’).
- ✔ Check Engine Light is on with codes like P0700 (Transmission Control System Malfunction), P0750, or other solenoid-specific faults.
- ✔ Delayed or no engagement when shifting from Park to Drive or Reverse.
- ✔ Poor acceleration and a noticeable drop in fuel economy.
- ✔ The transmission seems to slip or fails to upshift or downshift correctly.
A Straightforward Guide to Installation
One of the best features of this module is its simple, direct-fit installation. For a DIYer with basic tools, this is a job you can complete in your driveway in under 30 minutes. The location on the 2007-2009 Tahoe is typically right next to the battery in the engine compartment.
- Safety First: 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 Old TCM: Find the module, usually mounted to a bracket next to the battery. It will have several large electrical connectors attached.
- Disconnect and Remove: Carefully unplug the wiring harnesses. They have locking tabs that may need to be gently pried up. Once disconnected, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, VIN-programmed TCM into place. Securely reconnect the wiring harnesses, ensuring they click into place.
- Final Steps: Reconnect the negative battery terminal. While the module is plug-and-play, it’s always a good practice to use a basic OBD2 scan tool to clear any stored diagnostic trouble codes (DTCs) from the system. Start the vehicle and test drive to confirm smooth shifting.
Verified Fitment for Your Vehicle
This T42 Transmission Control Module is a direct replacement for part number 24239224 and is interchangeable with a wide range of other GM service numbers. It is guaranteed to fit the following models, but please verify your specific options.
- Chevrolet Tahoe: 2007, 2008, 2009 (w/o auxiliary oil cooler pump)
- Chevrolet Silverado 1500: 2007-2013
- GMC Yukon / Yukon XL 1500: 2007-2009
- GMC Sierra 1500: 2007-2013
- Chevrolet Avalanche 1500: 2007-2008
- Chevrolet Suburban 1500: 2007-2008
- …and many other GM vehicles including Express/Savana vans, Impala, HHR, Cobalt, Canyon/Colorado, and more from 2006-2014. Please see the full fitment list for details.
Frequently Asked Questions
Do I need to take this part to a dealer for programming?
No. This is the biggest benefit of our service. We program the module to your vehicle’s VIN before it ships. This makes the installation plug-and-play, saving you the time and expense of a dealership visit.
Is this a difficult part to replace myself?
Not at all. For most vehicles like the 2007-2009 Tahoe, the TCM is easily accessible in the engine bay. With basic hand tools, the replacement should take less than 30 minutes, making it an ideal DIY repair.
Will this fix a P0700 check engine light code?
A P0700 code is a general fault request from the TCM to the main engine computer (ECU). If the root cause is a failing TCM, then replacing it with this module will resolve the code. However, P0700 can also be triggered by other transmission issues, so a full diagnosis is always recommended.
Is there a core charge for my old part?
No, there is no core charge. You are not required to send your old, faulty module back to us, which simplifies your repair process.