If your 2006-2007 Terraza is struggling with harsh shifting, getting stuck in gear, or throwing transmission codes, you’re not just dealing with a vehicle problem—you’re dealing with a family safety and reliability issue. As a technician with over two decades of experience, I’ve seen countless GM minivans just like the Terraza come into the shop with these exact symptoms. The culprit is almost always a failing Transmission Control Module (TCM). This VIN-programmed T42 TCM, part number 24255280, is the definitive, dealership-free solution to restore your van’s performance and your peace of mind.
The TCM is the electronic brain of your automatic transmission. It controls everything from when the gears shift to how smoothly the torque converter engages. When it starts to fail, due to heat cycles and electronic wear, the symptoms can range from annoying to dangerous. This module is engineered to OEM specifications and arrives pre-programmed to your Terraza’s specific Vehicle Identification Number (VIN), ensuring it works perfectly right out of the box. You get a reliable, long-term fix without the exorbitant cost and hassle of dealership programming.
A Technician’s Notebook: The Terraza That Wouldn’t Shift
A customer brought in their ’07 Terraza, explaining it would intermittently refuse to shift out of 2nd gear—a classic limp mode symptom. They were worried about a full transmission rebuild, a repair that can cost thousands. After a quick scan, I saw the tell-tale P0700 (Transmission Control System Malfunction) code. Instead of jumping to the worst-case scenario, I checked the TCM. Sure enough, it was failing. We replaced it with one of our VIN-programmed T42 modules. In under an hour, the van was shifting like new. The customer saved a fortune and drove away with a reliable family vehicle, all thanks to a simple, direct-fit electronic part.
Is Your Terraza Showing These Telltale Signs?
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:
- ✔ Harsh, jerky, or delayed gear shifts that make driving uncomfortable.
- ✔ The vehicle is stuck in a single gear (limp mode) to protect the transmission from further damage.
- ✔ The Check Engine Light or a dedicated transmission warning light is illuminated on your dash.
- ✔ Diagnostic Trouble Codes (DTCs) are present, such as P0700, P0750-P0758 (solenoid circuit faults), or U-series communication codes.
- ✔ A noticeable drop in fuel economy as the transmission operates inefficiently.
- ✔ Complete loss of communication with the module, preventing the vehicle from starting or shifting out of Park.
Simple Installation to Restore Your Drive
One of the best features of this part is its straightforward installation, perfect for the DIY mechanic. For the 2006-2007 Terraza, the TCM is conveniently located, making the job quick and easy.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electronic work.
- Locate the Module: On your Terraza, the TCM is typically found on the driver’s side of the engine bay, mounted to the LH strut tower.
- Disconnect and Remove: Carefully unplug the electrical connectors. Use a socket wrench to remove the mounting bolts holding the old TCM in place.
- Install the New TCM: Mount the new, pre-programmed module in the same location and securely fasten the bolts. Reconnect the electrical harnesses until they click.
- 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 fault codes from the vehicle’s memory.
The Definitive Fix for Your 2006-2007 Terraza TCM
Don’t let a faulty transmission module keep your family off the road. This part offers a permanent solution that restores the precise, smooth operation your vehicle was designed for. It’s built to last and backed by our one-year warranty, giving you confidence in your repair. By controlling shift points and hydraulic pressure correctly, it not only improves drivability but also helps protect the long-term health of your transmission’s mechanical components.
Verified Compatibility for Your Vehicle
This T42 Transmission Control Module is a direct-fit replacement for part number 24255280 and is compatible with a wide range of General Motors vehicles. While this page is focused on the Terraza, it also fits:
- Buick Terraza: 2006-2007 (Transmission; LH strut tower)
- Chevrolet Uplander: 2006-2009 (Transmission; LH strut tower)
- Pontiac Montana: 2006-2009 (Transmission; LH strut tower)
- Saturn Relay: 2006-2007 (Transmission; LH strut tower)
- …and many other GM cars, trucks, and SUVs from 2006-2014. Please verify the part number for your specific vehicle.
Do I need to take this part to a dealer for programming?
Do I need to take this part to a dealer for programming?
No. This Transmission Control Module comes fully pre-programmed to your vehicle’s VIN. It is a true plug-and-play solution, saving you a trip to the dealership and additional programming fees.
What is the warranty on this 2006-2007 Terraza TCM?
We stand behind our parts with a comprehensive one-year warranty, covering any defects or malfunctions for your peace of mind.
Is this a new or used part?
This is a high-quality, inspected, and tested OEM-grade component that has been expertly programmed with the latest GM software for your vehicle. It meets or exceeds original factory performance standards.
Do I need to send my old part back?
No, there is no core charge for this module. You can keep or dispose of your old part without any hassle or extra fees.