Restore Your Buick’s Performance with a Reliable TCM
If your 2006-2007 Buick Rainier is suffering from erratic shifting, getting stuck in gear, or throwing transmission codes, you’ve come to the right place. As a technician with over two decades of experience, I’ve seen countless GM vehicles sidelined by a faulty Transmission Control Module (TCM). The T42 module is the electronic brain of your automatic transmission, and when it fails, it can cause a cascade of frustrating and potentially damaging issues. This replacement TCM, part number 24241806, is the definitive solution to get your Rainier driving smoothly again.
This isn’t just a part; it’s a complete, ready-to-install fix. We pre-program each module to your vehicle’s specific VIN, loading the latest GM software updates. This critical step ensures perfect communication between the engine and transmission, eliminating the need for an expensive trip to the dealership for programming. For a DIY enthusiast or a professional mechanic, this means less downtime and a more efficient repair, restoring the precise shifting and torque converter control your vehicle had when it was new. A faulty TCM is a common failure point, but with this direct-fit replacement, it’s a problem you can solve with confidence.
A Technician’s Notebook
I remember a 2007 Rainier that came into the shop with a classic ‘ghost’ problem. The owner complained of intermittent harsh downshifts and occasional failure to shift out of 2nd gear, but only after driving for 20+ minutes. There were no consistent hard faults, just a generic P0700 (Transmission Control System Malfunction) code stored. After checking the wiring and fluid, we focused on the TCM. Heat soak was causing internal components to fail intermittently. Installing a new, VIN-programmed 2006-2007 Rainier TCM didn’t just fix the problem—it provided a permanent solution that gave the owner their confidence back on the road.
Is Your Buick Rainier Showing These Telltale Signs?
A failing TCM often gives clear warnings. If you’re experiencing any of the following, it’s a strong indicator that your module needs replacement. Ignoring these symptoms can lead to more severe transmission damage down the line.
- ✔ Harsh, jerky, or delayed gear shifts.
- ✔ Vehicle is stuck in “limp mode” (usually 2nd or 3rd gear).
- ✔ Check Engine Light or Transmission Warning Light is on.
- ✔ Diagnostic Trouble Codes (DTCs) such as P0700, P0750, or other solenoid-related faults are present.
- ✔ The transmission refuses to upshift or downshift properly.
- ✔ A noticeable decrease in fuel economy.
- ✔ Complete loss of communication with the transmission.
DIY Installation Guide: A 30-Minute Fix
One of the best features of this module is its straightforward installation. You don’t need a lift or specialized tools, making it a perfect weekend project for a DIYer. In most Rainier models, the TCM is easily accessible in the engine bay.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent electrical shorts and reset the system.
- Locate the Module: On the 2006-2007 Rainier, the TCM is typically found in the engine compartment. Check near the air cleaner box or on the driver’s side of the engine bay.
- Disconnect and Remove: Carefully unplug the electrical connectors. They have locking tabs, so be gentle. Then, unbolt the old module from its mounting bracket.
- Install the New TCM: Bolt the new module into place and securely reconnect the electrical harnesses. You’ll hear a click when they are properly seated.
- Final Steps: Reconnect the battery terminal. Start the vehicle and let it idle for a few minutes. While our programming clears most faults, it’s good practice to use a basic OBD2 scanner to clear any remaining stored codes.
Verified Vehicle Compatibility
This T42 Transmission Control Module is a direct replacement for a wide range of General Motors vehicles. While this page is dedicated to the 2006-2007 Rainier TCM, it is also compatible with the following models. Please verify your specific model and options.
This part fits:
- Buick Rainier: 2006-2007
- Buick Allure / LaCrosse: 2006-2009
- Buick Lucerne: 2006-2011
- Buick Rendezvous: 2006-2007
- Cadillac DTS: 2006-2011
- Chevrolet Cobalt, HHR, Impala, Malibu, Monte Carlo: See specific year ranges in fitment data.
- Chevrolet Colorado, Silverado, Tahoe, Suburban, Express Van: See specific year ranges in fitment data.
- GMC Canyon, Sierra, Yukon, Savana Van: See specific year ranges in fitment data.
- Hummer H3: 2008-2010
- Pontiac G5, G6, Grand Prix: See specific year ranges in fitment data.
- Saab 9-7X: 2006-2009
- Saturn Aura, Ion, Vue: See specific year ranges in fitment data.
This module interchanges with part numbers: 24252114, 24234503, 24230461, 24241806, and others.
Frequently Asked Questions
Frequently Asked Questions
Do I need to program this 2006-2007 Rainier TCM?
No! That’s the best part. We handle all the programming for you. Simply provide your vehicle’s VIN at checkout, and the module will arrive at your door ready for a plug-and-play installation, saving you hundreds in dealership fees.
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. Replacing it with our pre-programmed module is a very common and effective fix for this code, especially if accompanied by shifting symptoms.
How difficult is the installation?
For most DIYers with basic hand tools, this is a very manageable job that takes less than 30 minutes. The module is located in the engine bay, making it easy to access without lifting the vehicle.
Is there a core charge for my old part?
No, there is no core charge. You can keep your old part or recycle it locally without the hassle of shipping it back to us.
What kind of warranty is included?
This transmission control module is backed by our one-year, hassle-free warranty, giving you peace of mind with your purchase.