Tired of Harsh Shifting in Your Buick Lucerne?
If your 2006-2011 Buick Lucerne is suffering from erratic shifting, delayed gear engagement, or has you stuck in limp mode, you’re not just dealing with an annoyance—you’re facing a common and frustrating problem. As a technician with over two decades of experience, I’ve seen countless GM vehicles sidelined by a failing Transmission Control Module (TCM). The symptoms can appear suddenly, leaving you with an unreliable and unpleasant driving experience. This isn’t just about comfort; it’s about the health of your transmission and your safety on the road. A faulty TCM can lead to poor fuel economy, transmission overheating, and eventually, catastrophic internal damage.
A Technician’s Notebook: The Case of the Lagging Lucerne
A customer brought in their 2008 Lucerne with the classic complaints: a violent bang when shifting from 1st to 2nd gear and the check engine light glaring at them. A quick scan revealed a P0700 (Transmission Control System Malfunction) code. While this is a generic code, my experience pointed directly to the T42 TCM. These modules, located in the hot engine bay, are prone to failure from heat cycles and vibration. Instead of a costly diagnostic rabbit hole and a multi-day stay at the dealership for programming, we installed one of our pre-programmed modules. The entire job took less than an hour, the codes were cleared, and the car shifted as smoothly as the day it left the factory. This is the exact, reliable fix we offer you.
Is Your Buick Exhibiting These Transmission Issues?
A failing TCM will give you clear warning signs. If you’re experiencing any of the following, it’s highly likely your module is the culprit. Ignoring these symptoms can lead to more expensive transmission repairs down the line.
- ✔ Harsh, jerky, or unpredictable gear shifts.
- ✔ The vehicle gets stuck in one gear (often called “limp mode”).
- ✔ Check Engine Light or Transmission Warning Light is on.
- ✔ Diagnostic Trouble Codes (DTCs) are present, such as P0700, P0750, or other solenoid-related faults.
- ✔ Delayed engagement when shifting from Park to Drive or Reverse.
- ✔ A noticeable decrease in fuel efficiency.
- ✔ Complete failure to shift gears.
A Straightforward Guide to Installation
Replacing the 2006-2011 Lucerne TCM is a job most DIY enthusiasts can handle in their own garage in under 30 minutes. For the Buick Lucerne, you’ll find the module in the left-hand (driver’s side) of the engine compartment. Follow these simple steps for a successful installation.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts and to help reset the system.
- Locate the Module: On your Lucerne, the TCM is typically found in the LH engine compartment. It’s a small metal box with electrical connectors.
- Disconnect and Remove: Carefully unplug the electrical harnesses from the old TCM. Then, unbolt the module from its mounting bracket.
- Install the New Module: Bolt your new, VIN-programmed TCM into place. Securely reconnect the electrical harnesses, ensuring they click into place.
- Final Steps: Reconnect the negative battery terminal. Start the vehicle and use a basic OBD2 scan tool to clear any stored fault codes. Take the car for a test drive to confirm the smooth shifting performance.
Verified Vehicle Compatibility
This T42 Transmission Control Module, part number 24239224, is guaranteed to fit your 2006-2011 Buick Lucerne. It is also a direct replacement for a wide range of other General Motors vehicles. Please confirm your model and year from the list below. This module is interchangeable with part numbers including 24252114, 24234503, 24230461, 24234274, and more.
Partial Fitment List:
- Buick Lucerne: 2006-2007 (4.6L), 2008-2011 (All) – Located in LH engine compartment.
- Chevrolet Impala: 2006-2011 – Located under lower air cleaner housing.
- Chevrolet Silverado 1500: 2007-2013 – Located next to battery.
- GMC Sierra 1500: 2007-2013 – Located next to battery.
- Cadillac DTS: 2006-2011 – Located in RH front engine compartment.
- …and many more GM models.
Frequently Asked Questions
Do I need to take this part to a dealer for programming?
No. This is the biggest benefit we offer. We program the module to your vehicle’s specific VIN before shipping it. This makes the installation plug-and-play, saving you hundreds of dollars and the hassle of a dealership visit.
What is a T42 TCM?
The T42 is the hardware designation for a specific generation of Transmission Control Module used by General Motors in many of their vehicles with 4-speed automatic transmissions, like the 4L60E and 4L65E, from roughly 2006 to 2014.
Will this fix a P0700 code?
While a P0700 code is a general fault indicator, it is very commonly triggered by a failing TCM. If you are experiencing shifting problems along with this code, a new module is the most probable solution.
Is there a core charge for my old part?
No, there is no core charge. You can keep or dispose of your old module without any need to send it back to us, making the process simple and hassle-free.
What kind of warranty is included?
This module is backed by our one-year, no-hassle warranty, giving you peace of mind with your purchase.