Restore Smooth Shifting to Your Buick Allure
If you’re dealing with the frustration of a Buick Allure that shifts harshly, gets stuck in gear, or throws transmission-related check engine lights, you’ve come to the right place. As a technician with over two decades of experience, I’ve seen countless GM vehicles, including the 2006-2009 Allure, suffer from these exact symptoms. The culprit is almost always a failing Transmission Control Module (TCM). This isn’t just an annoyance; it’s a critical failure that affects your car’s performance, fuel economy, and safety. This OEM-quality T42 TCM, service part number 24234503, is the definitive, reliable solution to get your vehicle driving like new again.
A Technician’s Notebook
I remember a 2008 Buick LaCrosse (which shares the same platform as the Allure) that came into the shop with an intermittent shifting problem. The owner had already spent money replacing a couple of shift solenoids, but the issue persisted. The car would drive fine for days, then suddenly slam into gear or refuse to upshift. After connecting my scan tool, I saw a generic P0700 code but no specific solenoid faults. Experience pointed me straight to the TCM. Heat soak and vibration had caused internal board failures that weren’t consistent enough to trip a specific code every time. We installed a VIN-programmed TCM, and the problem was solved instantly. This is a classic failure mode for these T42 modules.
Is Your Buick Allure Showing These Telltale Signs?
A failing TCM will give you clear warnings. If you’re experiencing any of the following, it’s time for a replacement. Ignoring these can lead to more significant transmission damage down the line.
- ✔ Harsh, erratic, or delayed gear shifts that make driving uncomfortable.
- ✔ The vehicle is stuck in “limp mode,” often locked in 2nd or 3rd gear.
- ✔ Check Engine Light or Transmission Warning Light is on, with Diagnostic Trouble Codes (DTCs) like P0700 (Transmission Control System Malfunction) or P0750-series solenoid codes.
- ✔ Complete failure to upshift or downshift, leading to poor acceleration and high RPMs.
- ✔ A noticeable drop in fuel efficiency as the transmission operates inefficiently.
- ✔ Intermittent loss of communication with the module or total transmission failure.
The Critical Advantage of a Pre-Programmed 2006-2009 Allure TCM
The single biggest hurdle in replacing a modern electronic module is programming. This module eliminates that problem entirely. We flash it with the latest GM software updates specifically for your vehicle’s VIN before it ships. This means no expensive trips to the dealership, no special scan tools required for setup, and no compatibility headaches. It’s a true plug-and-play fix that restores OEM functionality and communication between your engine and transmission for optimal performance.
Simple Swap: Your 30-Minute Installation Guide
This is a repair that a confident DIYer or any professional mechanic can complete quickly. For the 2006-2009 Buick Allure, the TCM is conveniently located for easy access.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the Module: On your Allure, the TCM is typically found attached to the lower air cleaner housing in the engine bay.
- Disconnect and Remove: Carefully unplug the electrical connectors. Note the locking tabs to avoid damage. Then, unbolt the old module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed TCM into place. Securely reconnect the electrical connectors 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 scanner to clear any stored fault codes from the system. Start the vehicle and enjoy smooth, correct shifting.
Confirmed Vehicle Compatibility List
This T42 Transmission Control Module is a direct fit for a wide range of General Motors vehicles. While this page is focused on the Buick Allure, please verify your model and location below. This module is interchangeable with part numbers 24252114, 24230461, 24234274, and more.
This part will fit these makes and models with these options
ALLURE 06-09 Transmission; (lower air cleaner housing)
AVALANCHE 1500 07-08 Transmission; (next to battery)
CANYON 08-12 Transmission; (RH rear engine compartment)
COBALT 06-10 Transmission; (LH strut tower)
… and many more GM models.
Frequently Asked Questions
What does ‘VIN Programmed’ mean for my Allure?
It means we load the module with your car’s specific Vehicle Identification Number (VIN) and the latest GM software before we ship it. This ensures it communicates perfectly with your car’s other computers right out of the box, just like a part from the dealer, but without the extra programming fee.
Do I need to take my car to a dealer after installation?
No. Because the module arrives pre-programmed to your VIN, you can skip the dealership visit entirely. This saves you time and the typical $100-$200 programming charge.
Is this installation difficult for a DIY mechanic?
Not at all. For the Buick Allure, the TCM is located under the air cleaner housing, making it one of the easier modules to access. With basic hand tools, the swap should take less than 30 minutes.
My old part has a different number on it. Will this still work?
Yes, most likely. GM uses many different service numbers for the same part over its production life. This module (part #24234503) is a common replacement for dozens of other part numbers. Check our full interchange list or contact us to confirm compatibility.
What is the warranty on this TCM?
This module comes with a one-year warranty, giving you peace of mind that you’re installing a quality, reliable part built to meet or exceed OEM standards.
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 shipping it back to us.