Restore Your Buick’s Smooth, Confident Shifting
Is your 2006-2011 Buick Lucerne suffering from jarring shifts, delayed gear engagement, or a frustrating check engine light? You’re not alone. The Transmission Control Module (TCM) is the brain of your automatic transmission, and when it fails, it can make your comfortable sedan feel unpredictable and unsafe. Over my 20+ years in the garage, I’ve seen countless GM vehicles, including the Lucerne, come in with these exact issues. The culprit is almost always a faulty T42 TCM, often compromised by years of heat and vibration in the engine bay.
This isn’t just a replacement part; it’s a complete, hassle-free solution. We provide a high-quality T42 Transmission Control Module, interchangeable with part number 24243901, that comes fully programmed to your vehicle’s specific VIN. This means you can skip the expensive trip to the dealership for programming. It arrives at your door ready for a plug-and-play installation, designed to restore the precise, smooth performance you expect from your Buick.
A Technician’s Notebook: The Intermittent Shifting Mystery
A customer brought in a 2008 Lucerne with a complaint that stumped two other shops: intermittent, violent downshifts when coming to a stop, but only after driving for 30+ minutes. There were no hard codes stored, just a generic P0700 (Transmission Control System Malfunction) in history. We monitored live data and saw the TCM command signals dropping out randomly once the engine bay was fully heat-soaked. The internal processors were failing under thermal stress. We installed a VIN-programmed T42 module, and the problem was solved instantly. This is a classic failure mode, and a pre-programmed module is the most efficient fix.
Is Your Buick Lucerne Showing These Telltale Signs?
A failing TCM doesn’t always mean a complete transmission breakdown. Watch for these early warning signs. Addressing them with a reliable 2006-2011 Lucerne TCM can prevent more serious damage.
- ✔ Harsh, banging shifts or erratic gear hunting.
- ✔ The vehicle gets stuck in one gear (often called “limp mode”).
- ✔ Check Engine Light or Transmission Warning Light is illuminated.
- ✔ Diagnostic Trouble Codes (DTCs) like P0700, P0750, or other solenoid-related faults are present.
- ✔ A noticeable delay when shifting from Park to Drive or Reverse.
- ✔ Poor fuel economy and a feeling of sluggish performance.
- ✔ Complete loss of communication with the transmission module.
A Straightforward Guide to Installation
Replacing the TCM on your Buick Lucerne is a job most DIYers can handle in under 30 minutes with basic hand tools. This will get you back on the road without a costly shop visit.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the Module: On the 2006-2011 Lucerne, the TCM is typically found in the left-hand (driver’s side) engine compartment. Check near the strut tower or under the air cleaner housing.
- Disconnect and Remove: Carefully unclip the electrical connectors. Be gentle to avoid damaging the pins or clips. Then, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed TCM into place. Reconnect the electrical connectors, ensuring they click securely into position.
- Final Steps: Reconnect the battery terminal. While our programming handles the critical setup, it’s good practice to use a basic OBD2 scanner to clear any lingering fault codes from the ECU. Start the vehicle and test drive to confirm smooth shifting.
Verified Vehicle Compatibility
This T42 TCM, part number 24243901, is a direct-fit, programmed solution for the 2006-2011 Lucerne TCM requirement. It is also compatible with a wide range of other General Motors vehicles from 2006-2014, including but not limited to:
- Buick: LaCrosse, Allure, Rendezvous, Rainier
- Chevrolet: Silverado, Tahoe, Impala, Cobalt, HHR, Express Van
- GMC: Sierra, Yukon, Savana Van, Envoy, Canyon
- Cadillac: DTS
- Pontiac: G6, Grand Prix
- Saturn: Vue, Aura, Ion
- And more… Please verify the part number or use our vehicle selector to confirm an exact match.
Frequently Asked Questions
What does ‘VIN Programmed’ actually mean for me?
It means the module arrives ready to install right out of the box. We load it with the latest GM software that is specific to your car’s Vehicle Identification Number (VIN). This ensures perfect communication with your engine computer and other systems, eliminating the need for expensive dealership programming.
Will this part fix a P0700 trouble code?
A P0700 code is a general fault code indicating the TCM has detected a problem. While this module often resolves the root cause (like an internal TCM failure that triggers the P0700), you should always diagnose any other specific codes (like for solenoids) that appear alongside it. In many cases, a new TCM is the correct fix.
Is any special relearn procedure required after installation?
No. Because the module is pre-programmed to your VIN, no special scan tools or complex relearn procedures are necessary. Simply install the part, clear any old codes with a standard scanner, and drive. The adaptive learning strategy will adjust fine-tuning on its own over the next few drive cycles.
Where is the TCM located on my 2007 Buick Lucerne?
For the 2006-2011 Buick Lucerne, the Transmission Control Module is located in the engine compartment on the driver’s side (LH side), often near the strut tower or integrated with the air cleaner housing.
Is there a core charge for my old part?
No, there is no core charge. You are not required to send your old, faulty module back to us, which simplifies the process for you.