Restore Smooth, Reliable Shifting to Your Buick LaCrosse
Is your 2006-2009 Buick LaCrosse suffering from jarring shifts, delayed gear engagement, or getting stuck in limp mode? These are classic signs of a failing Transmission Control Module (TCM). As the electronic brain of your automatic transmission, a faulty TCM can cripple your vehicle’s performance and drivability. This OEM-quality T42 Transmission Control Module, part number 24243901, is the definitive solution, arriving pre-programmed to your vehicle’s specific VIN for a true plug-and-play repair.
A Technician’s Notebook: The All-Too-Common LaCrosse Shifting Problem
I’ve lost count of how many GM vehicles, especially the Buick LaCrosse and Impala from this era, have rolled into my bay with the same complaint: “It feels like it’s getting rear-ended every time it shifts.” The owner is frustrated, the check engine light is on, and a quick scan reveals a P0700 (Transmission Control System Malfunction) and usually a specific solenoid code like P0752. In over 90% of these cases, the root cause isn’t a costly internal transmission failure, but a breakdown of the original TCM. Heat cycles and vibrations cause internal circuits to fail, leading to erratic commands. Replacing it with a pre-programmed unit like this one isn’t just a repair; it’s a permanent fix that gets the car driving like new again in under an hour.
Is Your Buick LaCrosse Showing These Telltale Signs?
A failing TCM will give you clear warnings. If you’re experiencing any of the following, it’s time to diagnose the module:
- ✔ Hard, slamming shifts or unpredictable gear changes.
- ✔ The vehicle is stuck in a single gear (often 2nd or 3rd), known as “limp mode.”
- ✔ Your Check Engine Light or Transmission Warning Light is illuminated.
- ✔ Diagnostic Trouble Codes (DTCs) are present, such as P0700, P0750, P0752, or other solenoid-related faults.
- ✔ Failure to upshift or downshift, resulting in poor acceleration and terrible fuel economy.
- ✔ Complete loss of communication with the module, preventing the vehicle from starting or shifting out of Park.
The Smart Solution: A Pre-Programmed 2006-2009 LaCrosse TCM
Don’t waste time and money at the dealership on diagnostics and programming fees. We take care of the most critical step for you. By providing your vehicle’s VIN during checkout, we program the module with the latest GM software updates specific to your LaCrosse. This ensures perfect communication between the engine and transmission, restoring precise shift points and torque converter lock-up for optimal performance and fuel efficiency. It’s a reliable, cost-effective fix for both professional mechanics and DIY enthusiasts.
DIY-Friendly Installation in Under 30 Minutes
You don’t need to be a master mechanic to install this part. For the 2006-2009 Buick LaCrosse, the TCM is conveniently located under the air cleaner housing, making it easily accessible.
- 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: Remove the air cleaner box assembly to access the old TCM.
- Disconnect and Remove: Carefully unplug the electrical connectors from the old module. Then, unbolt it from its mounting bracket.
- Install the New TCM: Mount your new, pre-programmed module in place, securely reconnect the electrical harnesses, and reinstall the air cleaner box.
- Final Steps: Reconnect the battery terminal. While the module is plug-and-play, it’s good practice to use a basic OBD2 scan tool to clear any stored fault codes from the vehicle’s memory.
Verified Fitment for Your General Motors Vehicle
This T42 TCM is a direct replacement for part number 24243901 and interchanges with numerous other GM service numbers. It fits a wide range of vehicles, including:
- Buick: LaCrosse (06-09), Allure (06-09), Lucerne (06-11), Rainier (06-07), Rendezvous (06-07)
- Chevrolet: Silverado 1500/2500 (07-13), Tahoe (07-09), Suburban 1500 (07-08), Avalanche 1500 (07-08), Impala (06-11), Monte Carlo (06-07), Cobalt (06-10), HHR (06-11), Colorado (08-12), Express/Savana Vans (06-14), Malibu (06-10), SSR (05-06)
- GMC: Sierra 1500/2500 (07-13), Yukon / Yukon XL 1500 (07-09), Envoy / Envoy XL (06-09), Canyon (08-12)
- Pontiac: G6 (06-10), Grand Prix (06-08), G5 (07-10), Pursuit (06)
- Saturn: Vue (07-10), Aura (07-09), Ion (06-07)
- Cadillac: DTS (06-11)
- Hummer: H3 (08-10)
- Saab: 9-7X (06-09)
Do I need to take this module to a dealer for programming?
Do I need to take this module to a dealer for programming?
No. This is the biggest benefit of our service. We pre-program the module to your vehicle’s VIN before shipping. It arrives ready for immediate installation, saving you hundreds in dealership fees and towing costs.
Where is the TCM located on my 2007 Buick LaCrosse?
On the 2006-2009 Buick LaCrosse, the Transmission Control Module is typically found bolted to the lower air cleaner housing in the engine bay, making it one of the easier locations to access.
Will this part fix a P0700 trouble code?
A P0700 code is a general fault code indicating the TCM has detected a problem. Often, a failing TCM is the source of this code. While this module is the most common fix, you should always diagnose any other codes (like solenoid codes) that appear alongside the P0700 to confirm the diagnosis.
Is there a core charge for my old part?
No, there is no core charge. You can keep your old module or dispose of it without the hassle of returning it, simplifying the repair process for you.
Do I need to take this module to a dealer for programming?
Do I need to take this module to a dealer for programming?
No. This is the biggest benefit of our service. We pre-program the module to your vehicle’s VIN before shipping. It arrives ready for immediate installation, saving you hundreds in dealership fees and towing costs.
Where is the TCM located on my 2007 Buick LaCrosse?
On the 2006-2009 Buick LaCrosse, the Transmission Control Module is typically found bolted to the lower air cleaner housing in the engine bay, making it one of the easier locations to access.
Will this part fix a P0700 trouble code?
A P0700 code is a general fault code indicating the TCM has detected a problem. Often, a failing TCM is the source of this code. While this module is the most common fix, you should always diagnose any other codes (like solenoid codes) that appear alongside the P0700 to confirm the diagnosis.
Is there a core charge for my old part?
No, there is no core charge. You can keep your old module or dispose of it without the hassle of returning it, simplifying the repair process for you.