If your 2006-2011 Buick Lucerne is suffering from erratic shifting, getting stuck in gear, or throwing transmission codes, 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 catastrophic transmission failure, causing unnecessary stress and costly misdiagnoses. This T42 TCM, part number 24241806, is the definitive, reliable solution to restore your vehicle’s performance and peace of mind.
This isn’t just a part; it’s a complete fix. We pre-program each module to your vehicle’s specific VIN, loading the latest GM software updates. This critical step ensures perfect communication between the engine and transmission, eliminating the need for an expensive trip to the dealership for programming. It arrives at your door ready for a true plug-and-play installation, getting your Lucerne back to the smooth, predictable ride you expect.
A Technician’s Notebook: The Lucerne That Limped In
A customer brought in their ’09 Lucerne, convinced the transmission was shot. It was stuck in 3rd gear (limp mode) and shifting with a hard bang into drive. The check engine light was on, and their local shop quoted them over $3,000 for a transmission rebuild. I scanned it and found a classic P0700 (Transmission Control System Malfunction) and a few solenoid circuit codes. Instead of pulling the pan, I checked the TCM connectors first—they were clean. Experience told me this was likely an internal TCM failure, a common issue on these platforms. We installed one of our VIN-programmed T42 modules. In under an hour, the car was shifting perfectly, all codes were gone, and the customer saved thousands. It’s often the brain, not the brawn, that fails.
Is Your Buick Exhibiting These Transmission Woes?
A faulty TCM can cause a wide range of frustrating symptoms. Before you condemn the entire transmission, check if your vehicle is showing any of these common signs of a failing 2006-2011 Lucerne TCM:
- ✔ Harsh, delayed, or unpredictable gear shifts.
- ✔ The vehicle is stuck in a single gear, often called “limp mode.”
- ✔ Check Engine Light or Transmission Warning Light is illuminated.
- ✔ Diagnostic Trouble Codes (DTCs) are present, such as P0700, P0750-series solenoid codes, or communication errors.
- ✔ A noticeable decrease in fuel economy.
- ✔ The transmission feels like it’s slipping between gears.
- ✔ Inability to shift into or out of a specific gear.
A Straightforward Guide to Your TCM Installation
You don’t need to be a master mechanic to replace this module. For the Buick Lucerne, the TCM is conveniently located in the engine compartment on the driver’s side, making it an accessible DIY job that typically takes less than 30 minutes.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before beginning any electrical work. This prevents short circuits and helps reset the vehicle’s electronic systems.
- Locate the Module: On your Lucerne, you’ll find the TCM in the left (driver’s side) engine compartment. It’s a silver box with electrical connectors.
- Disconnect and Remove: Carefully unplug the wiring harness connectors. They have locking tabs that need to be released. Once disconnected, unbolt the old module from its mounting bracket.
- Install the New Module: Bolt your new, VIN-programmed TCM into place. Securely plug in the wiring harness connectors, ensuring they click to confirm a solid connection.
- Final Steps: Reconnect the negative battery terminal. Start the vehicle and allow it to idle for a few minutes. While our programming resolves most codes, it’s good practice to use a basic OBD2 scanner to clear any stored DTCs. Take the car for a test drive to confirm the smooth shifting performance.
Verified Fitment for Your Vehicle
While this is the correct part for the 2006-2011 Lucerne TCM, this versatile T42 module also fits a wide array of other General Motors vehicles. Please verify your part number or consult the list below. This module is an interchangeable replacement for service numbers such as 24252114, 24234503, 24241806, and more.
- Buick: Lucerne (2006-2011), LaCrosse, Allure, Rainier, Rendezvous, Terraza
- Chevrolet: Silverado, Tahoe, Suburban, Impala, Monte Carlo, Cobalt, HHR, Express, Colorado, Avalanche, SSR, Malibu, Uplander
- GMC: Sierra, Yukon, Savana, Envoy, Canyon
- Pontiac: G6, Grand Prix, G5, Montana, Pursuit
- Cadillac: DTS
- Saturn: Vue, Aura, Ion
- Hummer: H3
- Saab: 9-7X
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. The main benefit of our service is that we pre-program the module to your vehicle’s VIN before shipping. This makes the installation plug-and-play, saving you the time, cost, and hassle of a dealership visit.
What is the warranty on this TCM?
This module is backed by our one-year, hassle-free warranty. We stand by the quality and reliability of our parts to ensure you can buy with confidence.
How do I know for sure that the TCM is the problem?
While the symptoms listed are strong indicators, the best way to be certain is with a proper diagnosis. A professional scan tool can read transmission-specific codes (like P0700) and check for communication with the TCM. If there’s a communication failure or specific internal circuit codes for the TCM, it’s very likely the culprit.
Is there a core charge for my old part?
No, we do not require a core return. You can keep your old part, which simplifies the process for you. No need to worry about shipping a core back to us.