Restore Smooth, Reliable Shifting to Your Pontiac Montana
As a technician with over two decades of experience, I know how frustrating it is when your family’s minivan starts acting up. A Pontiac Montana with a transmission that hesitates, slams into gear, or gets stuck in limp mode isn’t just an annoyance—it’s a reliability issue. The culprit is often a failing Transmission Control Module (TCM), the electronic brain that manages every aspect of your automatic transmission’s performance. This T42 TCM, part number 24243921, is the definitive solution to get your van back to running the way it should.
We take the guesswork and extra cost out of the repair. Unlike a generic part from the auto parts store, each module is expertly programmed to your vehicle’s specific VIN before it ships. This means it arrives ready for a true plug-and-play installation, with no need for an expensive trip to the dealership for programming. It’s a direct fix that restores communication between your engine and transmission, ensuring precise shift timing, correct torque converter lockup, and dependable performance for years to come.
Case Study: The Intermittent Limp Mode
I once had a 2008 Montana in my bay that was a real head-scratcher for the owner. It would drive perfectly for days, then suddenly drop into limp mode (stuck in 3rd gear) with a P0700 code. After checking the wiring and solenoids, which all tested fine, we traced the issue to the TCM. Under-hood heat and vibrations had caused an intermittent failure on the circuit board. Swapping in a VIN-programmed T42 module like this one permanently solved the problem. The customer was thrilled to have their reliable family vehicle back without a costly diagnostic chase.
Is Your Montana Showing These 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 2006-2009 Montana TCM problem.
- ✔ Harsh, erratic, or delayed gear shifts.
- ✔ The vehicle is stuck in one gear (often called “limp mode”).
- ✔ Check Engine Light or Transmission Warning Light is illuminated.
- ✔ Diagnostic Trouble Codes (DTCs) are present, such as the general code P0700 or various solenoid-specific codes (e.g., P0750, P0753, P0758).
- ✔ A noticeable decrease in fuel economy.
- ✔ The transmission feels like it’s slipping or failing to engage properly.
A Straightforward Guide to Installation
For the handy DIYer, replacing the 2006-2009 Montana TCM is a simple job that can be done in your driveway in under 30 minutes. No specialized tools are required.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts and help reset the system.
- Locate the Module: On the 2006-2009 Pontiac Montana, the TCM is conveniently located at the driver’s side strut tower in the engine bay.
- Disconnect and Remove: Carefully unplug the electrical connectors from the old TCM. Then, unbolt the module from its mounting bracket and remove it from the vehicle.
- Install the New TCM: Mount your new, pre-programmed TCM onto the bracket and securely re-fasten the bolts. Reconnect the electrical connectors, ensuring they click into place.
- Final Steps: Reconnect the negative battery terminal. While our programming resolves most codes, it’s good practice to use a basic OBD2 scanner to clear any stored DTCs before starting the vehicle.
Verified Vehicle Compatibility
This module is a direct replacement for part number 24243921 and other interchangeable numbers. It is guaranteed to fit the following models:
- Pontiac Montana: 2006, 2007, 2008, 2009 (Transmission; LH strut tower)
- Note: This T42 TCM also fits a wide range of other GM vehicles including the Uplander, Terraza, G6, Cobalt, HHR, Impala, and more. Please verify your part number or contact us to confirm fitment.