Restore Peak Performance to Your Buick’s Transmission
Is your 2006-2007 Buick Rainier suffering from erratic shifting, delayed gear engagement, or a frustrating “limp mode”? These are classic signs of a failing Transmission Control Module (TCM). The TCM is the electronic brain of your automatic transmission, responsible for orchestrating every gear change and ensuring smooth, efficient operation. When it fails, it can cause a host of drivability issues and illuminate your check engine light, leaving you stranded or with an unreliable vehicle. This replacement GM T42 Transmission Control Module, service part number 24255280, is the definitive solution to restore your vehicle’s factory performance.
From the Diagnostic Bay
We recently had a 2007 GMC Yukon come into the shop with the check engine light on and complaints of harsh, unpredictable shifting. The owner had already replaced two shift solenoids based on the diagnostic trouble codes (DTCs), but the problem persisted. Our technician connected a high-level scan tool and monitored the TCM data. We saw erratic commands being sent to the solenoids, even the new ones. This pointed directly to an internal failure in the original TCM. Instead of another costly and incorrect repair, we installed one of our VIN-programmed T42 modules. After a 25-minute installation and clearing the old codes, the Yukon shifted perfectly. The customer was thrilled to have his truck back on the road without the constant worry of transmission issues, saving him from a potential trip to the dealership for expensive programming.
Diagnosing a Faulty Rainier Transmission Control Module
A failing TCM can manifest in various ways, often mimicking other transmission problems. By recognizing the specific symptoms, you can accurately diagnose the issue and get the right part the first time. This module is the key to resolving these frustrating and potentially damaging conditions.
Common Symptoms of TCM Failure
- ✔ Erratic and Harsh Shifting: Your vehicle may slam into gear, hesitate between shifts, or shift at incorrect RPMs.
- ✔ Stuck in Gear / Limp Mode: The transmission may refuse to shift out of a single gear (often 2nd or 3rd) to prevent further damage.
- ✔ Warning Lights: The Check Engine Light or a dedicated transmission warning light will illuminate on your dashboard.
- ✔ Diagnostic Trouble Codes (DTCs): You’ll likely see codes such as P0700 (Transmission Control System Malfunction) or various solenoid-specific codes (e.g., P0750, P0751).
- ✔ Delayed Engagement: A noticeable delay when shifting from Park into Drive or Reverse.
- ✔ Poor Fuel Economy: Inefficient shifting and torque converter lockup issues can lead to a significant drop in gas mileage.
- ✔ Complete Communication Loss: In severe cases, the TCM may stop communicating with the Engine Control Module (ECM) and other vehicle systems entirely.
The Plug-and-Play Advantage: VIN Programming Included
One of the biggest hurdles in replacing modern electronic modules is the need for expensive, dealer-specific programming. We eliminate this step completely. Before shipping, we program this Rainier Transmission Control Module to your vehicle’s specific Vehicle Identification Number (VIN). This process loads the latest GM software and calibrations, ensuring the module works seamlessly with your Rainier’s engine and transmission hardware right out of the box. There is no need for a trip to the dealership or the use of a specialized scan tool for setup. This is a true plug-and-play solution designed for both professional technicians and DIY installers.
Key Features & Benefits:
- VIN-Programmed for Your Vehicle: Arrives ready for installation with no additional programming required.
- Restores Smooth Shifting: Corrects issues like harsh shifts, slipping, and delayed engagement by restoring precise electronic control.
- Clears Common DTCs: A properly functioning TCM is essential for resolving persistent transmission-related trouble codes.
- OEM-Quality Construction: Built to meet or exceed original equipment standards for durability and long-term reliability.
- No Core Charge: Keep your old part without the hassle or expense of a core return.
- Broad Compatibility: Interchangeable with a wide range of part numbers including 24242391, 24234503, 24252114, and many others, fitting popular 4-speed automatic transmissions like the 4L60E, 4L65E, and 4L70E.
Frequently Asked Questions
What does a Transmission Control Module do?
The Transmission Control Module (TCM) acts as the central computer for your automatic transmission. It uses data from various sensors to control shift solenoids, regulate hydraulic pressure, and manage torque converter lockup, ensuring smooth and efficient gear changes.
Is this TCM difficult to install?
Installation is generally straightforward for someone with basic mechanical skills. The module is typically located in the engine compartment (e.g., next to the battery or under the air cleaner box). The process involves disconnecting the battery, unplugging the electrical connectors, unbolting the old module, and installing the new one. The entire job often takes less than 30 minutes.
Will I need to go to a dealership after installation?
No. Because we pre-program the module to your vehicle’s VIN, there is no need for any additional programming or setup at a dealership. It is designed to be a plug-and-play repair.
How do I provide my vehicle’s VIN?
You will be prompted to enter your vehicle’s 17-digit VIN during the checkout process. Please double-check it for accuracy, as this is critical for correct programming.
Does this part fit other vehicles besides the Buick Rainier?
Yes, this T42 TCM is compatible with a wide range of 2006-2014 General Motors vehicles, including models like the Chevrolet Silverado, Tahoe, Impala; GMC Sierra, Yukon; Cadillac DTS; and Pontiac G6, among many others. Please verify the part number or use our vehicle fitment tool to confirm compatibility.