Restore Dependable Shifting to Your Pontiac Montana
Is your 2006-2009 Pontiac Montana struggling with harsh shifts, getting stuck in gear, or showing a persistent check engine light? These are classic signs of a failing Transmission Control Module (TCM). As the electronic brain of your automatic transmission, the TCM is responsible for every gear change. When it fails, it can make your family’s daily driver feel unpredictable and unsafe. This replacement T42 TCM, part number 24235732, is the definitive solution to restore your vehicle’s performance and your peace of mind.
Over my two decades in automotive diagnostics, I’ve seen countless GM vehicles, from work vans to family minivans, sidelined by faulty electronics. The T42 TCM is a frequent culprit, but the fix doesn’t have to be a costly trip to the dealership. We solve the biggest hurdle for you: programming. Each module is expertly programmed to your vehicle’s specific VIN before it ships. This means no expensive scan tools or dealer appointments are needed. It arrives ready for a true plug-and-play installation, getting your Montana back to shifting smoothly and efficiently.
From the Diagnostic Bay: The Intermittent Limp Mode Mystery
A customer brought in their ’08 Montana, complaining that it would randomly get stuck in 3rd gear—a classic limp mode symptom. They had already replaced two shift solenoids based on a generic code reading, but the problem persisted. After hooking up my pro-level scanner and monitoring live data, I saw the TCM was intermittently dropping communication altogether. The root cause wasn’t the solenoids; it was the module itself failing under heat. We installed a VIN-programmed 2006-2009 Montana TCM, and the problem was solved permanently. This highlights why replacing the module is often the correct, long-term fix for persistent electronic transmission codes.
Is Your Montana Showing These Telltale Signs of TCM Failure?
A failing TCM can manifest in several ways. If you’re experiencing any of the following, it’s a strong indicator that your module needs replacement. Catching it early can prevent further damage to your transmission.
- ✔ Harsh, banging, or erratic gear shifts.
- ✔ The vehicle is stuck in one gear (limp mode) and won’t shift up or down.
- ✔ Delayed engagement when shifting from Park to Drive or Reverse.
- ✔ Check Engine Light or Transmission Warning Light is on with codes like P0700, P0753, or P0758.
- ✔ Poor acceleration and a noticeable drop in fuel economy.
- ✔ Complete loss of communication with the TCM, leading to a no-shift condition.
A Straightforward Guide to Your 2006-2009 Montana TCM Installation
This is a repair you can confidently handle in your own driveway. For the Pontiac Montana and similar GM minivans (Uplander, Terraza), the TCM is typically easy to access. Follow these steps for a successful installation.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts and to help reset the system.
- Locate the Module: On your Montana, the TCM is usually found mounted to the driver’s side strut tower in the engine bay. It’s a silver box with two large electrical connectors.
- Disconnect and Remove: Carefully unplug the two wiring harness connectors. They have locking tabs that need to be released. Then, unbolt the module from its mounting bracket.
- Install the New TCM: Mount the new, pre-programmed module in the same location. Securely plug in the two wiring harness connectors until they click into place.
- Final Steps: Reconnect the battery terminal. Start the vehicle and let it idle for a few minutes. If you have a basic scan tool, it’s good practice to clear any stored fault codes. Take the vehicle for a test drive to confirm smooth shifting.
Verified Vehicle Compatibility
This T42 TCM is a direct replacement for part number 24235732 and is interchangeable with many other GM service numbers. While this page focuses on the 2006-2009 Montana TCM, it also fits a wide range of other GM cars, trucks, and SUVs. Please verify your specific model in the list below.
- Pontiac Montana (2006-2009): Transmission; (LH strut tower)
- Buick Terraza (2006-2007): Transmission; (LH strut tower)
- Chevrolet Uplander (2006-2009): Transmission; (LH strut tower)
- Pontiac G6 (2006-2010): Transmission; (LH strut tower)
- Chevrolet Cobalt (2006-2010): Transmission; (LH strut tower)
- Chevrolet HHR (2006-2011): Transmission; (LH engine compartment)
- Saturn Ion (2006-2007): Transmission; (behind LH strut tower)
- And many more GM models from 2006-2014.
Frequently Asked Questions
What exactly does this Transmission Control Module do?
The TCM is the computer that controls all electronic functions of your automatic transmission. It reads data from various sensors to determine the perfect moment to shift gears, control line pressure, and engage the torque converter clutch, ensuring both smooth performance and optimal fuel efficiency.
Is this part really plug-and-play?
Yes. We pre-program the module to your vehicle’s VIN before shipping. This crucial step ensures it communicates perfectly with your vehicle’s other computers (like the ECM and BCM) right out of the box, eliminating the need for a trip to the dealer for expensive programming.
Will this fix my check engine light for a P0700 code?
A P0700 code is a general fault code indicating the TCM has detected a problem. In many cases where the TCM itself is the source of the fault (due to internal failure), replacing it with this module will resolve the P0700 and any related specific transmission codes (like solenoid circuit faults).
Do I need any special tools for installation?
No special tools are required. Basic hand tools, such as a socket set to remove the mounting bolts and a wrench for the battery terminal, are all you should need for this straightforward job.
Is there a core charge for my old part?
No, there is no core charge. You can keep your old part, so there’s no need to worry about the cost or hassle of shipping it back to us.