Restore Your Buick’s Smooth Ride: The Definitive Fix for Transmission Faults
If your 2006-2009 Buick Allure is suffering from harsh, erratic shifting, getting stuck in gear, or has the check engine light on with transmission codes, you’re not just dealing with an annoyance—you’re facing a failing Transmission Control Module (TCM). As a technician with over two decades of experience, I’ve seen countless drivers worry about a costly transmission rebuild when the real culprit is this electronic module. This replacement T42 TCM, part number 24255280, is the reliable, cost-effective solution you need. It comes fully pre-programmed to your vehicle’s VIN, eliminating the need for expensive dealership programming and getting you back on the road with confidence.
A Technician’s Notebook: The Intermittent Shifting Mystery
A customer brought in a 2008 Buick Allure with a frustrating problem: it would shift perfectly for days, then suddenly start slamming into gear and refuse to upshift. No check engine light was on, but a deep scan pulled a history code for P0752 (Shift Solenoid ‘A’ Stuck On). We checked the fluid and internal components, which were fine. The issue was heat-soak. After about 30 minutes of driving, the original TCM’s internal circuits would fail, causing the erratic commands. Swapping in a VIN-programmed T42 module like this one solved the problem instantly. It’s a classic failure mode for these units, and this part is the direct fix.
Is Your Buick Allure Showing These Signs?
A failing TCM can mimic more serious mechanical issues. Before you suspect a full transmission failure, check if you’re experiencing any of these common symptoms. This module is designed to correct them.
- ✔ Harsh, banging shifts or delayed gear engagement.
- ✔ Vehicle is stuck in “limp mode” (usually second or third gear).
- ✔ Check Engine Light is on with Diagnostic Trouble Codes (DTCs) like P0700, P0750, P0751, P0752, or other solenoid-related faults.
- ✔ The transmission refuses to upshift or downshift correctly.
- ✔ A noticeable drop in fuel economy and potential transmission overheating.
- ✔ Complete loss of communication with the transmission module.
A Straightforward Guide to Installation
For the DIY mechanic, this is one of the more accessible repairs you can perform. No specialized tools are required, and the process typically takes less than 30 minutes. On the 2006-2009 Buick Allure, the TCM is conveniently located under the lower air cleaner housing.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts and help reset the system.
- Access the Module: Remove the air cleaner box assembly to gain clear access to the TCM.
- Disconnect and Remove: Carefully unplug the electrical connectors from the old module. Then, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed TCM into place and securely reconnect the electrical harnesses. Ensure they click into place.
- Final Steps: Reinstall the air cleaner assembly and reconnect the battery. While the module is plug-and-play, it’s good practice to use a basic OBD2 scanner to clear any stored fault codes.
Verified Vehicle Compatibility
This module is a direct-fit replacement for the 2006-2009 Buick Allure. It is also compatible with a wide range of other General Motors vehicles equipped with 4-speed automatic transmissions like the 4L60E, 4L65E, and 4L70E. It is interchangeable with part numbers 24252114, 24234503, 24230461, 24255280, and more.
Frequently Asked Questions
Does this module require programming at a dealership?
No. We pre-program this module to your car’s specific VIN before shipping. It arrives ready for immediate installation, saving you time and money on dealer services.
What is a TCM and what does it do?
The Transmission Control Module (TCM) is the computer that controls your automatic transmission. It reads data from various sensors to manage shift points, torque converter lockup, and line pressure for smooth, efficient operation.
Will this fix a P0700 trouble code?
A P0700 code is a general fault code indicating the TCM has detected a problem. This module often resolves the underlying issue causing the P0700, such as failed solenoid drivers or internal processing errors. After installation, be sure to clear all codes.
Is there a core charge for my old part?
No, there is no core charge. You can keep your old part without the hassle of returning it.
What if I have questions during installation?
Our team of experts is here to help. We provide support to ensure your installation goes smoothly and your vehicle is running properly.