Restore Flawless Shifting to Your Chevrolet Trailblazer
Is your 2006-2009 Chevrolet Trailblazer suffering from jerky shifting, getting stuck in gear, or throwing transmission-related trouble codes? You’re not alone. The Transmission Control Module (TCM), the electronic brain of your automatic transmission, is a frequent point of failure. This replacement T42 TCM, part number 24240449, is the definitive solution to get your SUV driving like new again. Forget about costly trips to the dealership for programming—this module arrives at your door pre-loaded with your vehicle’s specific VIN data, making it a true plug-and-play fix for both professional technicians and DIY enthusiasts.
From the Diagnostic Bay: A Common Trailblazer Story
I recently had a 2008 Trailblazer come into my shop. The owner was frustrated—he’d been told he might need a full transmission rebuild. The vehicle would shift hard from 1st to 2nd, and occasionally it would refuse to shift out of 3rd gear, forcing him to pull over and restart the engine. A quick scan showed a P0700 (Transmission Control System Malfunction) and a P0752 (Shift Solenoid ‘A’ Stuck On). Instead of jumping to the expensive conclusion, we checked the basics. The fluid was clean, and the wiring was intact. Based on my experience with hundreds of these GM platforms, the culprit was clear: a failing TCM. We installed one of our VIN-programmed modules, and in under 30 minutes, the Trailblazer was shifting perfectly. It’s a textbook case of how this single part can solve a host of baffling transmission issues.
Is Your Trailblazer Exhibiting These Telltale Signs?
A faulty TCM can manifest in several ways. If you’re noticing any of the following, it’s a strong indicator that your module needs replacement:
- ✔ Abrupt, harsh, or delayed gear changes.
- ✔ The vehicle is stuck in ‘limp mode’ (often 2nd or 3rd gear only).
- ✔ Your Check Engine Light or a transmission warning light is on.
- ✔ Diagnostic Trouble Codes (DTCs) like P0700, P0750, P0751, or other solenoid-related codes are present.
- ✔ A noticeable drop in fuel economy.
- ✔ The transmission seems to slip between gears or fails to engage properly from Park.
The Smart Solution for Your 2006-2009 Trailblazer TCM
This isn’t just a replacement part; it’s a complete, hassle-free repair. By managing everything from shift points to torque converter lockup, this module restores the precise logic your transmission needs for optimal performance and longevity. Built to meet or exceed original equipment standards and backed by a one-year warranty, it provides lasting peace of mind.
DIY-Friendly Installation: A Step-by-Step Guide
Replacing the TCM on your Trailblazer is a straightforward job that can be done in your driveway with basic hand tools. On most 2006-2009 models, the module is conveniently located 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 system.
- Locate the Module: On the Trailblazer and Envoy, 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 module. Then, unbolt it from its mounting bracket.
- Install the New Module: Bolt the new VIN-programmed TCM into place and securely reconnect the electrical harnesses. Ensure they click into place.
- Final Steps: Reconnect the battery terminal. While the module is plug-and-play, it’s always good practice to use a basic OBD2 scan tool to clear any stored fault codes after the installation is complete.
Verified Fitment for Your GM Vehicle
While this is the perfect solution for the 2006-2009 Trailblazer, this T42 TCM is also compatible with a wide array of other General Motors vehicles. Please verify your specific model and part number. This part is interchangeable with service numbers including 24252114, 24234503, 24230461, 24234274, 24235340, 24256960, and 24240449.
- Chevrolet: Trailblazer (06-09), Tahoe (07-09), Silverado (07-13), Express Van (06-14), Impala (06-11), Cobalt (06-10), HHR (06-11), and more.
- GMC: Envoy (06-09), Sierra (07-13), Yukon (07-09), Savana Van (06-14), Canyon (08-12).
- Buick: Rainier (06-07), LaCrosse (06-09), Lucerne (06-11).
- Cadillac: DTS (06-11).
- Pontiac: G6 (06-10), Grand Prix (06-08).
- Saturn: Vue (07-10), Aura (07-09), Ion (06-07).
- Hummer: H3 (08-10).
- Saab: 9-7X (06-09).
Why is VIN programming so important?
VIN programming loads your vehicle’s unique software onto the module before it ships. This ensures it communicates perfectly with your engine computer (ECM) and other systems, eliminating the need for an expensive programming session at a dealership. It makes the installation a simple plug-and-play process.
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 internal shorts or failed drivers that trigger other codes), you should always confirm the specific codes stored alongside the P0700. This part is a direct fix for many of those underlying issues.
Is this a difficult part to install myself?
Not at all. For most DIYers with basic tools, this is a very accessible repair. The module is typically easy to access in the engine bay, and the process involves simply unbolting the old unit and plugging in the new one. Our step-by-step guide makes it even easier.
Do I need to send my old part back?
No. There is no core charge or requirement to return your old, faulty module. You can dispose of it at your convenience.
What is the warranty on this TCM?
This transmission control module comes with a comprehensive one-year warranty, giving you confidence and peace of mind in your repair.