Restore Your Minivan’s Drivability with a Reliable TCM
If your 2006-2009 Pontiac Montana is suffering from harsh, delayed, or unpredictable shifting, a failing Transmission Control Module (TCM) is the most likely culprit. As the electronic brain of your automatic transmission, the TCM orchestrates every gear change. When it fails, it can make your family vehicle feel unreliable and unsafe. This direct-fit T42 TCM, part number 24255280, 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 Common T42 Failure
In my 20+ years in the shop, I’ve seen hundreds of these GM T42 modules come across my bench. A frequent case involved a 2008 Montana that would intermittently get stuck in 3rd gear (limp mode), especially on hot days. The owner had already replaced a shift solenoid with no luck. A quick scan showed a P0700 (Transmission Control System Malfunction) and intermittent communication loss codes. The root cause wasn’t the transmission itself, but the TCM. Heat cycles and vibration can cause microscopic cracks in the circuit board’s solder joints, leading to the exact unpredictable behavior the customer described. Replacing the module with a pre-programmed unit like this one is a permanent fix that restores communication and proper function.
Is Your Montana Exhibiting These Transmission Issues?
- ✔ Harsh, banging shifts or delayed gear engagement.
- ✔ The vehicle is stuck in a single gear (known as “limp mode”).
- ✔ Check Engine Light or Transmission warning light is illuminated.
- ✔ Diagnostic Trouble Codes (DTCs) are present, such as P0700, P0750-P0758, or other solenoid-related faults.
- ✔ A complete loss of shifting ability or failure to go into gear.
- ✔ Poor fuel economy directly related to incorrect gear selection.
DIY-Friendly Installation Guide
Getting your Montana back in top shape is a straightforward job that most DIYers can complete in under 30 minutes with basic hand tools. This module is conveniently located for easy access.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting work.
- Locate the Module: On your 2006-2009 Montana, the TCM is mounted on the driver’s side (LH) strut tower in the engine bay.
- Disconnect and Remove: Carefully unplug the electrical connectors. Be gentle with the locking tabs. Then, unbolt the module from its mounting bracket.
- Install the New TCM: Mount the new module securely onto the bracket and plug in the electrical connectors until they click firmly into place.
- Final Steps: Reconnect the battery terminal. While our programming handles the critical setup, it’s best practice to use a basic OBD2 scan tool to clear any stored fault codes from the vehicle’s memory.
Key Features & Direct Benefits
- ✔ VIN-Specific Programming: We program the module to your Montana’s VIN before shipping. This eliminates the need for expensive dealership tools or programming fees, ensuring it works perfectly right out of the box.
- ✔ Restored Performance: Solves common issues like harsh shifting, limp mode, and false diagnostic codes, returning your transmission’s operation to factory-new smoothness.
- ✔ OEM-Grade Quality: Built to meet or exceed original equipment specifications for durability and long-term reliability under all driving conditions.
- ✔ No Core Charge: Keep your old part. There are no core fees or return hassles, simplifying your repair process.
- ✔ Broad Interchangeability: This T42 module, also known by part numbers 24234503, 24252114, and others, is a proven component across a wide range of GM vehicles.
Verified Vehicle Compatibility
This Transmission Control Module is a guaranteed fit for the following vehicles, including but not limited to:
Pontiac Montana 2006-2009 (located at LH strut tower)
It also fits many other GM models such as the Chevrolet Uplander, Buick Terraza, Saturn Relay, Pontiac G6, Chevrolet Cobalt, and more where the TCM is located at the LH strut tower. Always verify the part number for your specific application.
Frequently Asked Questions
Why is VIN programming so important for a TCM?
VIN programming loads your vehicle’s specific software, including transmission type, gear ratios, and tire size. Without it, the TCM cannot communicate correctly with the engine and other modules, leading to shifting problems or a no-start condition. Our service saves you a mandatory and costly trip to the dealer.
What tools do I need for installation?
Typically, you’ll only need a basic socket set to remove the mounting bolts and potentially a small flathead screwdriver to help release the connector tabs. No specialized electronic tools are required for the physical installation.
Will this fix a P0700 code?
A P0700 is a general code indicating the TCM has detected a fault. Often, the fault is internal to the TCM itself. Replacing a faulty TCM is a very common and effective way to resolve a P0700 code, especially when accompanied by other transmission-specific codes.
Is there a warranty with this part?
Yes, this module comes with our standard one-year warranty, giving you peace of mind and confidence in your repair.
Do I need to do a transmission relearn procedure?
Because the module comes pre-programmed with the latest GM software for your VIN, a formal relearn procedure is typically not required. The module will adapt as you drive. Simply install it, clear any old codes, and drive normally.