If the famously smooth ride of your 2006-2011 Buick Lucerne has been ruined by harsh shifts, warning lights, or a transmission that seems to have a mind of its own, you’ve likely pinpointed the culprit: a failing Transmission Control Module (TCM). As the electronic brain of your automatic transmission, the TCM is responsible for every gear change. When it fails, the results can range from annoying to dangerous. This isn’t a mechanical failure; it’s an electronic one, and I’ve seen it countless times in my 20+ years of diagnostics.
Don’t let a faulty module convince you that you need a costly transmission rebuild. This direct-fit T42 TCM, part number 24235340, is the reliable, cost-effective solution you need. We take all the guesswork and dealership hassle out of the equation. By programming the module to your vehicle’s specific VIN before it ships, we ensure it’s a true plug-and-play part. It arrives ready to install, pre-loaded with the latest GM software to restore the precise, seamless shifting performance you expect from your Buick.
Case Study: A Tricky Diagnosis
A customer brought in a 2008 Lucerne with the 4.6L V8. The complaint was intermittent, violent shifts and a transmission that would occasionally get stuck in 3rd gear (limp mode). They’d already replaced two shift solenoids based on a P0750-series code, but the problem persisted. After hooking up my scanner and monitoring live data, I saw the command signals from the TCM were dropping out randomly. The solenoids were fine; the TCM was the source of the problem. We installed one of our VIN-programmed T42 modules, and the car drove perfectly. It’s a classic example of how the right part saves hundreds in wasted labor and parts.
Is Your Lucerne Showing These Transmission Faults?
A failing 2006-2011 Lucerne TCM can manifest in several ways. If you’re experiencing any of the following, a replacement module is your most likely fix:
- ✔ Harsh, slamming, or delayed gear engagement.
- ✔ The vehicle is stuck in a single gear (often called “limp mode”).
- ✔ Check Engine Light or Transmission Warning Light is on.
- ✔ Diagnostic Trouble Codes (DTCs) are present, such as P0700 (Transmission Control System Malfunction) or other solenoid-related codes.
- ✔ Inconsistent shifting patterns or failure to upshift/downshift.
- ✔ A noticeable decrease in fuel economy.
- ✔ The transmission feels like it’s slipping between gears.
Plug-and-Play Installation: Get Back on the Road Fast
For the Buick Lucerne, this is a straightforward repair that a confident DIYer or any professional mechanic can complete in under 30 minutes. No complex wiring or special tools are needed.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electronic component replacement.
- Locate the Module: On the 2006-2011 Buick Lucerne, the TCM is typically found in the engine compartment, on the driver’s side (LH).
- Swap the Part: Carefully disconnect the wiring harnesses from the old module. Unbolt it from its mounting bracket and remove it. Install the new module in its place, re-secure the bolts, and firmly reconnect the wiring harnesses.
- Final Steps: Reconnect the battery terminal. While the module is pre-programmed, it’s best practice to use a standard OBD2 scan tool to clear any stored fault codes from the vehicle’s memory. Start the car and take it for a test drive to confirm smooth operation.
Verified Vehicle Compatibility
This T42 Transmission Control Module is a guaranteed fit for the following Buick Lucerne models. It also interchanges with a wide range of other GM vehicles, making it a versatile and reliable part.
- Buick Lucerne (2006-2007) with 4.6L V8 Engine (Location: LH engine compartment)
- Buick Lucerne (2008-2011) All Engines (Location: LH engine compartment)
This module, part number 24235340, is also a direct replacement for other service numbers including 24252114, 24234503, 24230461, 24234274, and more, ensuring broad compatibility across the GM family of vehicles from 2006-2014.
Frequently Asked Questions About the 2006-2011 Lucerne TCM
Do I need to take my car to the dealer for programming?
Absolutely not. We handle all the programming for you. Simply provide your vehicle’s VIN during checkout, and the module will arrive ready for immediate installation, saving you time and money.
Will this fix a P0700 trouble code?
A P0700 code is a general fault code indicating the TCM has detected a problem. In many cases, a faulty TCM is the root cause. Replacing it with this pre-programmed unit often resolves the P0700 and any related specific codes.
Is a core charge required?
No, we do not require a core charge. You can keep your old part, eliminating the hassle and expense of shipping it back.
What is the warranty on this part?
This module is backed by our one-year warranty, giving you peace of mind and confidence in your repair.
Is this a difficult part to install myself?
For most individuals with basic mechanical skills, this is a very manageable job. It’s located in an accessible part of the engine bay and involves simple hand tools. Following our installation guide should make the process smooth and quick.