Restore Peak Transmission Performance in Your Buick Rainier
Is your 2006-2007 Buick Rainier suffering from erratic shifting, delayed gear engagement, or a persistent check engine light? These are classic signs of a failing Transmission Control Module (TCM). As the electronic brain of your automatic transmission, a faulty TCM can disrupt communication between the engine and gearbox, leading to poor performance, reduced fuel efficiency, and even leaving you stranded in limp mode. This genuine OEM-quality T42 TCM, part number 24240400, is the definitive solution, arriving pre-programmed to your vehicle’s specific VIN for a true plug-and-play repair.
From the Diagnostic Bay
We recently had a 2007 Rainier roll into the shop with the owner complaining of harsh 1-2 shifts and the vehicle randomly refusing to shift past 3rd gear. The dashboard was lit up with a check engine light, and our scan tool pulled a P0700 transmission fault code. While this code is generic, further diagnostics pointed to intermittent communication loss from the TCM. Instead of quoting a costly transmission overhaul, we identified the original T42 module as the weak link. We installed a VIN-programmed unit just like this one, cleared the adaptive learn tables, and had the Rainier shifting smoothly on the test drive in less than 30 minutes. It’s a common issue where the electronics fail, not the mechanical components.
Symptoms of a Failing 2006-2007 Rainier TCM
A failing TCM can manifest in several ways. If you’re experiencing any of the following, it’s highly likely your transmission control module needs replacement:
- ✔ Unpredictable, harsh, or slamming gear changes.
- ✔ Vehicle gets stuck in a single gear (often 2nd or 3rd), known as “limp mode.”
- ✔ The Check Engine Light or a dedicated transmission warning light is illuminated.
- ✔ Diagnostic Trouble Codes (DTCs) such as P0700, P0750, or other solenoid-related faults are present.
- ✔ Delayed engagement when shifting from Park to Drive or Reverse.
- ✔ A sudden and unexplained decrease in fuel economy.
- ✔ Complete failure to shift, resulting in the vehicle being inoperable.
Key Features & Direct Benefits
This module isn’t just a replacement part; it’s a complete solution designed to get your vehicle back on the road quickly and reliably.
- ✔ VIN Programmed for Your Rainier: We program the module with your vehicle’s specific VIN and the latest GM software updates before it ships. This eliminates the need for expensive dealership programming and ensures perfect communication with your vehicle’s other systems right out of the box.
- ✔ Restores Original Performance: By precisely controlling shift points, torque converter lockup, and line pressure, this TCM restores the smooth, efficient operation you expect from your vehicle’s 4-speed automatic transmission (4L60E, 4L65E, 4L70E).
- ✔ OEM-Standard Quality: Manufactured to meet or exceed General Motors’ stringent specifications, this module ensures long-lasting durability and reliable performance under all driving conditions. It is backed by a comprehensive one-year warranty for your peace of mind.
- ✔ Hassle-Free Installation: Designed as a direct-fit replacement, installation is straightforward. There is no core charge, so you can keep your old part without any extra hassle or fees.
Easy DIY Installation Guide
Replacing the TCM on your 2006-2007 Buick Rainier is a job most DIY mechanics can handle in under 30 minutes. The module is typically located in the engine compartment on the driver’s side. Always disconnect the vehicle’s battery before starting work to prevent electrical damage and help reset the system. Simply unbolt the old module, disconnect the wiring harnesses, and install the new one in its place. After reconnecting the battery, use a standard OBD2 scan tool to clear any stored diagnostic trouble codes. Your transmission will then begin a re-learning process to adapt to the new module, and normal operation will be restored.
Frequently Asked Questions
Do I need to take this part to a dealer for programming?
No. This Transmission Control Module comes fully pre-programmed to your vehicle’s VIN. It is ready for installation right out of the box, saving you time and the high cost of dealership programming services.
Where is the TCM located on my 2006-2007 Buick Rainier?
On the Buick Rainier and similar GMT360 platform vehicles (like the Trailblazer and Envoy), the TCM is typically found in the engine compartment, mounted on the driver’s side (LH) inner fender or near the strut tower.
Will this module fix a P0700 trouble code?
A P0700 code is a generic code indicating that the TCM has detected a fault. While this module often resolves the root cause of a P0700 code (internal TCM failure), you should ensure other components like wiring and solenoids are in good condition. In most cases, a faulty TCM is the primary culprit.
Is there a core charge for my old part?
No, there is absolutely no core charge. You are not required to send your old, faulty module back to us, which simplifies the repair process for you.
What kind of warranty comes with this part?
This module is backed by our one-year, hassle-free warranty, covering any defects in materials or workmanship for a full year from the date of purchase.