Restore Flawless Shifting to Your Chevrolet Trailblazer
If your 2006-2009 Chevrolet Trailblazer is suffering from erratic shifting, getting stuck in gear, or throwing transmission codes, the culprit is often a failing Transmission Control Module (TCM). As a hands-on technician with over two decades of experience, I’ve seen firsthand how a faulty TCM can mimic a major transmission failure, leading to costly and unnecessary repairs. This OEM-quality T42 TCM, part number 24235753, is the definitive solution to get your SUV back on the road with the smooth, reliable performance you expect.
The TCM is the brain of your automatic transmission, controlling everything from shift points and line pressure to torque converter lockup. When it fails, communication breaks down, resulting in the frustrating and sometimes dangerous symptoms you’re experiencing. Our module is meticulously tested and, most importantly, comes pre-programmed to your vehicle’s specific VIN. This eliminates the need for an expensive trip to the dealership for programming, making this a true plug-and-play fix for both professional mechanics and determined DIYers.
Case Study: The Trailblazer That Dodged a Rebuild
A customer brought in a 2008 Trailblazer with 130,000 miles. It was shifting hard from 1st to 2nd and occasionally would get stuck in 3rd gear (limp mode), with a P0753 code (Shift Solenoid ‘A’ Electrical). The owner had already been quoted over $2,500 for a transmission rebuild at another shop. After a quick diagnostic, I suspected the TCM. In my experience, these T42 modules are notorious for internal circuit failures that throw solenoid codes, even when the solenoids themselves are perfectly fine. We installed one of our VIN-programmed TCMs, cleared the codes, and the vehicle shifted perfectly. A 30-minute fix saved the customer thousands and restored their confidence in their vehicle.
Is Your Trailblazer Exhibiting These Telltale Signs?
A failing TCM will give you clear warnings. If you notice any of the following, it’s time to consider a replacement. Ignoring these symptoms can lead to further transmission damage.
- ✔ Harsh, banging shifts or delayed gear engagement.
- ✔ Vehicle stuck in “limp mode,” usually in 2nd or 3rd gear.
- ✔ Check Engine Light or Transmission Warning Light is on.
- ✔ Diagnostic Trouble Codes (DTCs) stored, such as P0700, P0750, P0753, P0758, or other solenoid-related faults.
- ✔ Complete loss of shifting, with the transmission not upshifting or downshifting.
- ✔ A noticeable drop in fuel economy due to inefficient shifting.
Your 30-Minute Path to a Smooth Ride
Installing your new 2006-2009 Trailblazer TCM is a straightforward process that you can complete in your own driveway with basic hand tools. For the 2006-2009 Trailblazer, the TCM is conveniently located in the engine compartment on the left-hand (driver’s) side.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts and to help reset the system’s memory.
- Locate the Module: Find the TCM in the LH engine compartment. It’s a silver box with electrical connectors.
- Disconnect and Remove: Carefully unplug the electrical harnesses. Then, unbolt the module from its mounting bracket.
- Install the New TCM: Mount the new, VIN-programmed TCM in the same location, securing it with the original bolts. Reconnect the electrical harnesses, ensuring they click securely into place.
- Final Steps: Reconnect the negative battery terminal. While our programming handles the critical data, it’s best practice to use a basic OBD2 scan tool to clear any lingering fault codes from the vehicle’s memory. Start the engine and take it for a test drive to confirm smooth operation.
Verified Fitment for Your GM Vehicle
This T42 Transmission Control Module is a direct replacement for part number 24235753 and is compatible with a wide range of General Motors vehicles equipped with 4-speed automatic transmissions like the 4L60E, 4L65E, and 4L70E. While this page focuses on the 2006-2009 Trailblazer TCM, it also fits:
- Chevrolet: Trailblazer (8-cyl), Trailblazer EXT, SSR, Express/Savana Vans, Silverado, Tahoe, Suburban, Avalanche, Cobalt, HHR, Impala, Monte Carlo, Colorado
- GMC: Envoy (8-cyl), Envoy XL, Sierra, Yukon, Yukon XL, Canyon
- Buick: Rainier, LaCrosse, Allure, Lucerne
- Pontiac: G6, Grand Prix, G5, Pursuit
- Cadillac: DTS
- Hummer: H3
- Saab: 9-7X
- Saturn: Vue, Ion, Aura
This module also interchanges with part numbers: 24242391, 24234503, 24252114, 24230461, 24234274, 24235340, 24235754, 24238856, and more. Order with confidence knowing you’re getting the right part, programmed and ready for installation.
Frequently Asked Questions
Do I need to take my vehicle to the dealer after installation?
No. This module comes fully programmed to your vehicle’s VIN. The service is included in the price, saving you time and the typical $150+ dealership programming fee. It is ready for installation right out of the box.
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 returning it.
Will this fix a P0700 transmission code?
A P0700 is a generic code indicating the TCM has detected a fault. Often, the root cause is the TCM itself. Replacing a faulty TCM will typically resolve the P0700 code along with the specific codes (like P0753) that triggered it.
What tools do I need for the installation?
For most vehicles, including the Trailblazer, you will only need basic hand tools, such as a socket set and a wrench to disconnect the battery terminal. No specialized equipment is required.
What if my part number is slightly different?
GM uses many interchangeable part numbers for the same module. As long as your vehicle is listed in our fitment guide, this T42 TCM will function correctly. The programming we perform ensures it works seamlessly with your specific vehicle.