Is Your Buick Lucerne Shifting Erratically?
If you’re experiencing harsh shifting, delayed gear engagement, or a check engine light on your 2006-2011 Buick Lucerne, a failing Transmission Control Module (TCM) is the most likely culprit. The TCM is the electronic brain of your automatic transmission, responsible for orchestrating every gear change, managing torque converter lockup, and ensuring smooth, efficient operation. When it begins to fail, it can cause a cascade of frustrating and potentially damaging issues, from poor fuel economy to being stuck in ‘limp mode’.
This genuine OEM-quality T42 TCM, service part number 24239224, is the definitive solution to restore your vehicle’s transmission performance. We take the guesswork and high dealership costs out of the equation by programming the module to your vehicle’s specific VIN number before it ships. This ensures a true plug-and-play installation, getting you back on the road quickly and confidently.
From the Diagnostic Bay
We had a 2008 Buick Lucerne come into the shop with the classic complaint: “It feels like it’s getting rear-ended every time it shifts from first to second.” The customer had already replaced two shift solenoids based on some forum advice, but the problem persisted. A quick scan showed a P0700 code (Transmission Control System Malfunction). Instead of just throwing more parts at it, we looked at the live data. We saw erratic command signals from the TCM. The internal processors were failing, sending junk data to perfectly good solenoids. We installed one of our VIN-programmed T42 modules, cleared the codes, and the car shifted like it just rolled off the assembly line. It’s a powerful reminder that the control unit is often the root cause, not just the components it commands.
Symptoms of a Failing T42 TCM
- ✔ Harsh or Erratic Shifting: Your vehicle may slam into gear, hesitate between shifts, or feel unpredictable during acceleration.
- ✔ Stuck in Gear / Limp Mode: The transmission may refuse to shift out of a single gear (often 2nd or 3rd) to prevent further damage.
- ✔ Warning Lights: The Check Engine Light or a dedicated transmission warning light will illuminate on your dashboard.
- ✔ Diagnostic Trouble Codes (DTCs): Common codes include P0700, which indicates a general transmission fault, and specific solenoid codes like P0751, P0756, etc.
- ✔ Delayed Engagement: A noticeable lag when shifting from Park into Drive or Reverse.
- ✔ Poor Fuel Economy: Inefficient shifting and torque converter operation can lead to a significant drop in MPG.
- ✔ No Communication: In severe cases, a scan tool may be unable to communicate with the TCM at all, indicating a complete failure.
Why Choose Our Programmed 2006-2011 Lucerne TCM?
This isn’t just a replacement part; it’s a complete, ready-to-install solution. The most critical aspect of replacing a modern TCM is the software programming. Our process ensures perfect integration with your vehicle’s existing systems.
- VIN Programmed for You: We flash the module with the latest GM software updates specific to your vehicle’s VIN. This eliminates the need for an expensive trip to the dealership for programming.
- OEM-Quality and Reliability: Built to meet or exceed original equipment specifications, ensuring long-lasting durability and dependable performance.
- Simple Installation: On the Buick Lucerne, the TCM is typically located in the LH (driver’s side) engine compartment. The replacement process is straightforward and can be completed in under an hour with basic hand tools. Disconnect the battery, unplug the old module, install the new one, and reconnect the battery.
- No Core Charge: Keep your old part. We don’t require a core return, saving you time and the hassle of shipping your old, faulty module back.
Broad GM Compatibility
While this is a perfect fit for the 2006-2011 Lucerne, this T42 TCM is also compatible with a wide range of GM vehicles equipped with 4-speed automatic transmissions like the 4L60E, 4L65E, and 4L70E. It directly interchanges with numerous part numbers, including 24252114, 24234503, 24230461, 24239926, and more, making it a versatile solution for many Chevrolet, GMC, Cadillac, Pontiac, and Saturn models from the same era.
Frequently Asked Questions
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 will arrive ready to install, requiring no further programming or setup. This is a true plug-and-play solution.
Where is the TCM located on my 2007 Buick Lucerne?
On the 2006-2011 Buick Lucerne, the Transmission Control Module is located in the engine compartment on the driver’s side (LH side).
Will this 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 of the P0700 and related specific codes (like solenoid faults), you should ensure the transmission wiring and components are in good condition. In most cases, a faulty TCM is the primary issue.
Is this compatible with other GM vehicles like a Silverado or Impala?
Yes, this T42 TCM is used across a vast range of GM vehicles from roughly 2006 to 2014, including the Silverado, Tahoe, Impala, GMC Sierra, and many more. As long as the part number matches and it’s for a compatible 4-speed automatic transmission, it will work once programmed to that vehicle’s VIN.
What is your warranty policy on this module?
This part is backed by our standard one-year warranty, covering any defects in the module itself. We stand behind the quality of our programmed electronics to give you peace of mind.