Is Your Buick Lucerne Shifting Erratically?
If your 2006-2011 Buick Lucerne is experiencing harsh shifting, delayed gear engagement, or has the check engine light illuminated with transmission-related codes, a failing Transmission Control Module (TCM) is the likely culprit. The TCM is the electronic brain of your automatic transmission, responsible for orchestrating shift points, managing torque converter lockup, and ensuring smooth, efficient operation. When it fails, it can lead to a host of drivability issues, poor fuel economy, and even leave you stranded in limp mode.
From the Diagnostic Bay
We had a 2008 Buick Lucerne come into the shop with classic symptoms of a bad transmission—slipping between gears and a P0700 code. The owner was convinced he needed a complete transmission rebuild, a costly and time-consuming job. However, after connecting our scan tool, we noticed erratic data from the shift solenoids. Instead of jumping to a mechanical failure, we inspected the TCM. After swapping in this pre-programmed T42 module, all the shifting problems vanished. The issue was purely electronic, saving the customer thousands of dollars and days of downtime. Always check the electronics first!
Key Symptoms of a Failing GM T42 TCM
- ✔ Harsh, jerky, or unpredictable gear shifts.
- ✔ Vehicle gets stuck in a single gear (limp mode), often 2nd or 3rd.
- ✔ Delayed engagement when shifting from Park to Drive or Reverse.
- ✔ Check Engine Light or Transmission Warning Light is on.
- ✔ Diagnostic Trouble Codes (DTCs) such as P0700, P0750, or other solenoid-specific codes are present.
- ✔ A noticeable decrease in fuel efficiency.
- ✔ The transmission seems to slip out of gear while driving.
Your Plug-and-Play Solution: The 2006-2011 Lucerne TCM
This genuine OEM-quality T42 Transmission Control Module is the definitive solution for your vehicle’s transmission woes. The most significant benefit is our complimentary VIN programming service. We flash the module with your vehicle’s specific VIN and the latest GM software updates before it ships. This ensures it communicates perfectly with your car’s powertrain control module (PCM) and other systems right out of the box. You can avoid the expensive trip to the dealership for programming, making this a simple, direct-fit replacement you can often perform yourself in under 30 minutes. This module restores the precise electronic control your transmission needs for optimal performance and longevity.
Installation is straightforward. For the Buick Lucerne, the TCM is typically found in the engine compartment on the driver’s side. Simply disconnect the battery, unplug the electrical connectors from the old module, unbolt it, and install the new one. Reconnect everything, and you’re ready to go. We recommend using a basic scan tool to clear any stored fault codes after installation to ensure a clean reset.
This module is not only for the Buick Lucerne but also fits a wide range of GM vehicles from 2006-2014 that use the T42 controller and 4-speed automatic transmissions like the 4L60E, 4L65E, and 4L70E. It is a direct replacement for multiple service numbers, including 24242391, 24234503, 24252114, and many more, ensuring broad compatibility.
Frequently Asked Questions
Do I need to get this module programmed by a dealer?
No. This module comes pre-programmed to your vehicle’s specific VIN. It is a true plug-and-play solution, saving you the time and expense of a dealership visit.
Where is the TCM located on my 2007 Buick Lucerne?
On the 2006-2011 Buick Lucerne, the Transmission Control Module is typically located in the engine compartment, on the driver’s side (LH side) of the vehicle, sometimes near the strut tower or under the air cleaner housing.
Will this fix a P0700 trouble code?
A P0700 code is a general transmission fault code, indicating that the TCM has detected a problem. While a faulty TCM is a very common cause, this code can also be triggered by other issues. However, if you are also experiencing erratic shifting or other symptoms listed, replacing the TCM is the most probable fix.
Is this compatible with other GM vehicles?
Yes, this T42 TCM is compatible with a wide array of GM vehicles, including models like the Chevrolet Impala, GMC Sierra, Cadillac DTS, and Pontiac G6 from roughly 2006 to 2014. Please verify the part number or use our vehicle fitment tool to confirm compatibility.
Is there a core charge for this part?
No, we do not require a core charge. You can keep your old part without the hassle of returning it.