Restore Your Buick’s Smooth Performance
If your 2006-2009 Buick LaCrosse is suffering from erratic shifting, getting stuck in gear, or throwing transmission-related check engine light codes, a failing Transmission Control Module (TCM) is often the root cause. As a technician with over two decades of diagnostic experience, I’ve seen countless GM vehicles, including the LaCrosse, sidelined by these exact issues. The T42 TCM is the electronic brain of your automatic transmission, and when it falters, the entire driving experience is compromised. This replacement T42 TCM, part number 24252114, is the definitive solution to get your vehicle back to factory-spec operation without the high cost and hassle of a dealership visit.
The Plug-and-Play Advantage: Pre-Programmed for Your LaCrosse
One of the biggest hurdles in replacing modern electronics is the need for expensive, proprietary programming. We eliminate that step entirely. Before this module ships, we program it directly to your vehicle’s VIN. This ensures that all the specific shift points, torque converter lockup strategies, and communication protocols for your 2006-2009 LaCrosse TCM are loaded and ready to go. The result is a true plug-and-play part that restores performance right out of the box, saving you time, money, and a trip to the service center.
A Technician’s Notebook: The Intermittent LaCrosse
A customer brought in a 2008 Buick LaCrosse with a frustrating problem: it would occasionally refuse to shift out of 2nd gear, but only after driving for 20-30 minutes. The check engine light was on with a general TCM code (P0700) and a solenoid performance code. After checking the wiring and fluid, we suspected the TCM was failing under heat. Instead of a costly diagnostic path, we recommended a VIN-programmed T42 module. The replacement took less than 30 minutes, and the problem was solved permanently. The customer avoided hundreds in dealership diagnostic fees and got a reliable fix.
Common Signs of a Failing LaCrosse TCM
- âś” Harsh, delayed, or unpredictable gear shifts.
- âś” Vehicle enters ‘limp mode,’ often stuck in 2nd or 3rd gear.
- âś” Check Engine Light is on with codes like P0700, P0750, or other transmission solenoid faults.
- âś” Complete failure to upshift or downshift, leading to poor acceleration.
- âś” A noticeable decrease in fuel economy.
- âś” The transmission warning light illuminates on the dashboard.
A Straightforward Guide to Installation
- âś” Safety First: Always disconnect the negative terminal from your vehicle’s battery before beginning any electronic component replacement.
- âś” Locate the Module: On the 2006-2009 Buick LaCrosse, the TCM is typically found under the air cleaner housing in the engine bay. You may need to remove the airbox for access.
- âś” Disconnect and Remove: Carefully unplug the electrical connectors from the old TCM. Then, unbolt the module from its mounting bracket.
- âś” Install the New Module: Mount the new VIN-programmed TCM in place of the old one and securely fasten it. Reconnect the electrical connectors, ensuring they click into place.
- âś” Final Steps: Reinstall the air cleaner housing and any other components you removed. Reconnect the battery terminal. While the module is plug-and-play, it’s good practice to use a basic scan tool to clear any stored fault codes from the vehicle’s memory.
Verified Vehicle Compatibility
This T42 TCM is a direct replacement for part number 24252114 and is compatible with a wide range of General Motors vehicles. While this page focuses on the 2006-2009 LaCrosse TCM, it also fits other models that use the 4L60E, 4L65E, and 4L70E transmissions, including:
- Buick LaCrosse (2006-2009) – located under lower air cleaner housing
- Buick Allure (2006-2009)
- Chevrolet Impala (2006-2011)
- Pontiac Grand Prix (2006-2008)
- And many other GM cars, trucks, and SUVs from 2006-2014. Please verify your part number or contact us with your VIN to confirm fitment.
Frequently Asked Questions
What does ‘VIN Programmed’ actually mean for me?
It means the module arrives ready for installation with no extra steps. We load your car’s specific software using your VIN, so it communicates perfectly with your engine and transmission, just like the original part.
Do I need any special tools to install this TCM?
No special tools are required. Basic hand tools like a socket set and screwdriver to access the module are all you’ll need. The installation is designed to be straightforward for a DIYer or any professional mechanic.
Will this fix my P0700 check engine light code?
If the code is being caused by a faulty TCM, then yes, this part is the direct solution. A P0700 code is a general fault request from the TCM to the ECM. Replacing a failing TCM will resolve the underlying issue causing the code.
Is there a core charge for my old part?
No, there is no core charge. You can keep your old part, which simplifies the process and saves you the hassle and cost of return shipping.