End Your Allure’s Transmission Troubles for Good
If you’re dealing with a 2006-2009 Buick Allure that shifts harshly, hesitates, or has thrown a transmission-related check engine light, you’ve come to the right place. As a technician with over two decades of experience, I’ve seen firsthand how a failing Transmission Control Module (TCM) can mimic a major mechanical failure, causing unnecessary stress and diagnostic headaches. This T42 TCM, part number 24235340, is the definitive, reliable solution to restore the crisp, predictable shifting your vehicle had when it was new.
The TCM is the electronic brain of your automatic transmission. It processes data from various sensors to command precise gear changes and manage torque converter lockup for optimal fuel efficiency. When it fails—often due to heat cycles and vibration under the hood—the symptoms can be alarming. This module is expertly pre-programmed to your vehicle’s specific VIN, ensuring it works perfectly right out of the box. You get a permanent fix without the costly trip to a dealership for programming.
A Technician’s Notebook: The Misleading Solenoid Code
A customer brought in a 2008 Buick LaCrosse (which uses the same T42 system as the Allure) with a P0752 code, indicating a ‘Shift Solenoid A Stuck On’ condition. He had already replaced the solenoid himself, but the harsh 1-2 shift and warning light remained. After a quick check of the wiring, I suspected the TCM. The driver circuits inside the module had failed, sending an incorrect signal to a perfectly good solenoid. We installed a VIN-programmed TCM, and the problem was solved in under 20 minutes. This is a classic example of how a faulty module can send you chasing the wrong parts—replacing the TCM first often saves time and money.
Is Your Allure Showing These Transmission Warning Signs?
A faulty TCM can manifest in several ways. If you’re experiencing any of the following, this module is the likely solution for your 2006-2009 Allure TCM issues:
- ✔ Harsh, slamming, or erratic gear shifts.
- ✔ The vehicle feels stuck in one gear (often called “limp mode”).
- ✔ Check Engine Light or Transmission Warning Light is illuminated.
- ✔ Diagnostic Trouble Codes (DTCs) are present, such as the general P0700 code or specific solenoid codes (e.g., P0750, P0751, P0752).
- ✔ Delayed engagement when shifting from Park to Drive or Reverse.
- ✔ A sudden drop in fuel economy.
DIY Installation: A 30-Minute Fix for Your Buick
One of the best features of this module is its simple, plug-and-play installation. No special tools are needed. For the Buick Allure, the TCM is typically located under the air cleaner housing, making it easily accessible.
- Safety First: Disconnect the negative terminal from your car’s battery to prevent any electrical shorts and to help reset the system.
- Locate the Module: Find the TCM, which is situated beneath the lower air cleaner housing in your Allure’s engine bay.
- Disconnect and Remove: Carefully unplug the electrical connectors from the old TCM. Then, unbolt the module from its mounting bracket and remove it from the vehicle.
- Install the New Module: Bolt the new, pre-programmed TCM into place and securely reconnect the electrical connectors. You’ll hear a click when they’re properly seated.
- Final Steps: Re-install the air cleaner housing and reconnect the battery terminal. Start the vehicle and allow it to idle for a few minutes. While not always necessary, using a basic OBD2 scanner to clear any stored codes is good practice.
Verified Fitment for Your General Motors Vehicle
This T42 TCM is a direct replacement for part number 24235340 and is interchangeable with many other GM service numbers. While this page focuses on the 2006-2009 Allure TCM, it also fits a wide range of other vehicles. Please verify your specific model and location below:
- Allure (2006-2009): Found in the lower air cleaner housing.
- Chevrolet Silverado/GMC Sierra (2007-2013): Typically located next to the battery.
- Chevrolet Impala/Monte Carlo (2006-2011): Found in the lower air cleaner housing.
- Pontiac G6/Saturn Aura (2006-2010): Located on the LH strut tower or frame rail.
- And many more GM models from 2006-2014.
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. We program the module to your vehicle’s VIN before shipping. It arrives ready for immediate installation, saving you hundreds in dealership programming fees.
Is this a difficult part to install myself?
Not at all. For a Buick Allure, the installation is very straightforward and typically takes less than 30 minutes with basic hand tools. It’s located under the air cleaner box for easy access.
Will this fix a P0700 trouble code?
A P0700 code is a general fault request from the TCM to the main computer. In a vast majority of cases I’ve diagnosed, a failing TCM is the root cause that triggers the P0700. Replacing the module is the correct fix.
What is the warranty on this module?
This module is backed by a one-year, hassle-free warranty. We stand behind the quality and reliability of our programmed electronics.
Do I need to send my old part back?
No, there is no core charge for this part. You can keep or recycle your old module without any obligation.