Fix Your 2006-2007 Buick Rainier’s Shifting Problems for Good
If you’re dealing with a Buick Rainier that’s shifting erratically, refusing to shift, or stuck in limp mode, you know how frustrating and concerning it can be. As a technician with over two decades of experience, I’ve seen countless drivers worry they’re facing a catastrophic transmission failure, only to find the culprit is a faulty Transmission Control Module (TCM). This VIN-programmed T42 TCM, part number 24238856, is the definitive, reliable solution to restore your vehicle’s performance and peace of mind.
The TCM is the brain of your automatic transmission, controlling everything from shift points to torque converter lockup. When it fails, the symptoms can mimic a major mechanical issue. This module is expertly pre-programmed to your vehicle’s specific VIN, ensuring it works perfectly right out of the box. You can skip the expensive trip to the dealership for programming—this is a true plug-and-play fix for the savvy DIYer or professional mechanic.
Case Study: The Rainier That Wouldn’t Shift
A customer brought in their ’07 Buick Rainier, convinced the 4L60E transmission was shot. It was stuck in 3rd gear (limp mode), and the check engine light was on. They’d gotten a quote for a full transmission rebuild that was over $3,000. I scanned the vehicle and pulled a P0700 (Transmission Control System Malfunction) and several solenoid codes. Instead of tearing down the transmission, I checked the TCM. After years of heat and vibration in the engine bay, the internal circuits had failed. We replaced it with one of our VIN-programmed modules. In less than an hour, the vehicle was shifting perfectly, all codes were cleared, and the customer saved thousands. This is a classic example of why proper diagnosis is key.
Is Your Buick Showing These Telltale Signs?
A failing TCM can manifest in several ways. If you’re experiencing any of the following, this module is likely the solution you need for your 2006-2007 Rainier Transmission Module.
- ✔ Harsh, delayed, or unpredictable gear shifts.
- ✔ Vehicle is stuck in a single gear (often called ‘limp mode’).
- ✔ Check Engine Light or Transmission Warning light is illuminated.
- ✔ Diagnostic Trouble Codes (DTCs) like P0700, P0750, or other solenoid-related faults are present.
- ✔ A noticeable drop in fuel economy.
- ✔ The transmission seems to slip out of gear.
- ✔ Complete loss of communication with the transmission module.
A Straightforward Guide to Installation
Replacing the TCM is a job most DIYers can handle in their own driveway in under 30 minutes. The location of the 2006-2007 Rainier Transmission Module is in the engine compartment, making it easily accessible.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the Module: On the Rainier, you will typically find the TCM in the engine compartment. Check common locations like next to the battery or under the air cleaner box.
- Disconnect and Remove: Carefully unplug the electrical connectors. Use a socket wrench to remove the bolts holding the old module in place.
- Install the New Module: Mount the new, pre-programmed TCM in the same location and secure it with the original bolts.
- Reconnect: Plug the electrical connectors firmly into the new module. Reconnect your battery terminal.
- Final Steps: Start the vehicle. The pre-programming ensures it’s ready to go, but it’s good practice to use a basic scan tool to clear any stored fault codes from the ECU.
Verified Vehicle Compatibility
This T42 TCM is a direct-fit replacement for a wide range of General Motors vehicles, including the 2006-2007 Rainier Transmission Module. It is interchangeable with part numbers 24252114, 24234503, 24238856, and more. Please see the comprehensive list below to confirm your specific model.
- Buick Allure (2006-2009)
- Buick LaCrosse (2006-2009)
- Buick Lucerne (2006-2011)
- Buick Rainier (2006-2007)
- Buick Rendezvous (2006-2007)
- Cadillac DTS (2006-2011)
- Chevrolet Avalanche 1500 (2007-2008)
- Chevrolet Cobalt (2006-2010)
- Chevrolet Colorado (2008-2012)
- Chevrolet Express/Savana Vans (2006-2014)
- Chevrolet HHR (2006-2011)
- Chevrolet Impala (2006-2011)
- Chevrolet Malibu (2006-2010)
- Chevrolet Monte Carlo (2006-2007)
- Chevrolet Silverado/Sierra Trucks (2007-2013) – *Check specific options*
- Chevrolet SSR (2005-2006)
- Chevrolet Suburban/Yukon XL (2007-2008)
- Chevrolet Tahoe/Yukon (2007-2009)
- Chevrolet Trailblazer/GMC Envoy (2006-2009)
- GMC Canyon (2008-2012)
- Hummer H3 (2008-2010)
- Pontiac G5/G6/Grand Prix (2006-2010)
- Pontiac Pursuit (2006)
- Saturn Aura (2007-2009)
- Saturn Ion (2006-2007)
- Saturn Vue (2007-2010)
- Saab 9-7X (2006-2009)
What does ‘VIN Programmed’ actually mean?
What does ‘VIN Programmed’ actually mean?
It means we load your vehicle’s unique 17-digit Vehicle Identification Number (VIN) and the latest GM software onto the module before we ship it. This ensures the TCM has the correct shift strategies and parameters for your specific engine, transmission, and options, making it a true plug-and-play part without needing a dealership visit.
Do I need any special tools for this installation?
No special tools are required. A basic socket set to remove the mounting bolts and a flathead screwdriver to help with connector clips are typically all you need. A code scanner is helpful for clearing old codes but not mandatory for the part to function.
Is there a core charge for my old part?
No, there is no core charge. You are not required to send your old, faulty module back to us, saving you time and return shipping costs.
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 failing TCM is the root cause that triggers the P0700 code. Replacing the module often resolves this and any related solenoid codes, but you should always confirm there are no underlying wiring or solenoid issues.