Restore Your Buick’s Smooth Ride
If your 2006-2011 Buick Lucerne is suffering from erratic shifting, getting stuck in gear, or has an illuminated check engine light, a failing Transmission Control Module (TCM) is the most likely cause. As the brain of your automatic transmission, the TCM dictates every gear change. When it fails, it can make your luxury sedan feel unpredictable and unsafe. This replacement T42 TCM, part number 24235732, is the definitive solution to restore your vehicle’s performance and your peace of mind.
We take the guesswork and high cost out of the repair by pre-programming this module to your vehicle’s specific VIN. This means it arrives ready for a direct, plug-and-play installation, with no expensive trip to the dealership required for programming. It’s a reliable fix designed for both professional mechanics and DIY enthusiasts who want to get their Lucerne back on the road quickly and affordably.
A Technician’s Notebook: The Intermittent Lucerne
I had a 2008 Buick Lucerne come into the shop with a complaint that was driving the owner crazy. Every few days, the transmission would slam into gear from a stop, and occasionally it would refuse to shift past 3rd gear. Of course, by the time it got to me, it was driving perfectly. There were no hard codes, just a stored P0700 (Transmission Control System Malfunction). After checking the fluid and wiring harness, everything looked fine. Experience pointed me toward the TCM. These T42 modules, especially after years of heat cycles in the engine bay, can develop internal faults that only show up under specific conditions. We swapped in a VIN-programmed module, and the problem was solved permanently. The customer was relieved to have his smooth, predictable car back.
Is Your Lucerne Exhibiting These Transmission Faults?
A faulty TCM can manifest in several ways. If you’re experiencing any of the following, it’s a strong indicator that your module needs replacement. Over my 20+ years, these are the most common symptoms I’ve seen tied directly to a failing 2006-2011 Lucerne TCM.
- âś” Harsh, delayed, or unpredictable gear shifts.
- âś” The vehicle feels like it’s stuck in one gear (limp mode).
- âś” Check Engine Light or Transmission Warning Light is on.
- âś” Diagnostic Trouble Codes (DTCs) such as P0700, P0750, or other solenoid-related faults are present.
- âś” A noticeable decrease in fuel economy.
- âś” Complete loss of communication with the transmission module.
A Straightforward Guide to Installation
Installing your new TCM is a simple process that can typically be completed in under 30 minutes with basic hand tools. For the Buick Lucerne, the module is conveniently located in the engine compartment.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts and to help reset the system.
- Locate the TCM: On the 2006-2011 Lucerne, you’ll find the Transmission Control Module in the left-hand (driver’s side) engine compartment.
- Disconnect and Remove: Carefully unplug the electrical connectors from the old module. Then, unbolt the module from its mounting bracket and remove it from the vehicle.
- Install the New Module: Bolt the new VIN-programmed TCM into place and securely reconnect the electrical connectors. Ensure they click into place.
- Final Steps: Reconnect the negative battery terminal. While the system may reset, it’s best practice to use a standard OBD2 scan tool to clear any lingering fault codes from the vehicle’s memory. Start the car and take it for a test drive to confirm the shifting is smooth.
Verified Vehicle Compatibility
This T42 TCM is a direct fit for a wide range of General Motors vehicles. While this listing is focused on the 2006-2011 Lucerne TCM, it is also compatible with the following models. Please verify your specific model and location notes.
- Buick Lucerne: 2006-2011 (LH engine compartment)
- Buick Allure / LaCrosse: 2006-2009 (lower air cleaner housing)
- Cadillac DTS: 2006-2011 (RH front engine compartment)
- Chevrolet Impala: 2006-2011 (lower air cleaner housing)
- Chevrolet Monte Carlo: 2006-2007 (lower air cleaner housing)
- Chevrolet Silverado / GMC Sierra: 2007-2013 (next to battery, check options)
- Chevrolet Tahoe / GMC Yukon: 2007-2009 (next to battery, check options)
- Chevrolet Express / GMC Savana: 2006-2014 (RH engine compartment)
- Pontiac Grand Prix: 2006-2008 (lower air cleaner housing)
- …and many more GM models from 2006-2014.
Why is VIN programming so important for this TCM?
Why is VIN programming so important for this TCM?
Your Buick Lucerne has specific software for its engine size, tire size, and gear ratios. Our VIN programming service installs this exact factory software onto the module before shipping. This ensures the transmission shifts correctly and communicates properly with other vehicle systems, eliminating the need for a dealership visit.
Will this part fix a P0700 trouble code?
Yes, in many cases. The P0700 code is a general fault request from the TCM to the main engine computer to turn on the check engine light. If the underlying cause is a faulty TCM, replacing it with this programmed unit will resolve the issue and allow the code to be cleared.
Is this a difficult part for a DIYer to install?
Not at all. For the Lucerne, the TCM is easily accessible in the engine bay. With basic tools and our plug-and-play programming, it’s one of the more straightforward electronic component replacements you can perform.
Do I need to send my old part back?
No, there is no core charge for this part. You can keep or dispose of your old module without any hassle or extra fees.
What does this TCM control?
The T42 TCM is responsible for managing critical transmission functions, including shift timing, shift pressure, torque converter clutch lockup, and transmission diagnostics. A properly functioning module is key to both performance and longevity.