Is Your Uplander’s Transmission Acting Up?
If you’re dealing with erratic shifting, a check engine light, or your 2006-2009 Chevrolet Uplander is stuck in one gear, a failing Transmission Control Module (TCM) is the most likely culprit. As a mechanic with over two decades of experience, I’ve seen how a faulty TCM can make a reliable family minivan feel unsafe and unpredictable. This module is the brain of your automatic transmission, and when it fails, it can cause a cascade of frustrating issues. This VIN-programmed T42 TCM is the direct-fit, reliable solution to get your vehicle running smoothly again without an expensive trip to the dealership.
From the Diagnostic Bay: The Intermittent Uplander
A customer brought in their ’07 Uplander with a complaint that stumped two other shops: intermittent, bone-jarring shifts, but only after driving for 30 minutes. There were no hard codes, just a generic P0700 (Transmission Control System Malfunction). After checking the fluid and solenoids, which were fine, I focused on the TCM. On these GM vans, the TCM is mounted on the LH strut tower, where it’s exposed to significant heat and vibration. Over time, this causes internal solder joints to crack. The fault only appeared when the module got hot enough for the crack to expand. We installed one of our pre-programmed T42 modules, and the problem was solved instantly. It’s a classic failure mode for these parts.
Common Signs of a Failing Uplander TCM
A bad transmission module can manifest in several ways. If you’re experiencing any of the following, it’s time to inspect your TCM:
- âś” Harsh, delayed, or unpredictable gear shifts that make driving uncomfortable.
- âś” The vehicle enters “limp mode,” often getting stuck in 2nd or 3rd gear.
- âś” Check Engine Light or Transmission Warning Light is illuminated on the dash.
- âś” Diagnostic Trouble Codes (DTCs) are stored, such as P0700, P0750-P0758 (solenoid circuit faults), or communication errors.
- âś” A noticeable drop in fuel economy as the transmission isn’t shifting efficiently.
- âś” The transmission feels like it’s slipping between gears or fails to engage from Park.
A Straightforward Guide to Installation
One of the best features of this module is its simple, DIY-friendly installation. Because we program it to your Uplander’s VIN before shipping, it’s a true plug-and-play part. You can do this job in your driveway in about 30 minutes.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent electrical shorts and help reset the system.
- Locate the TCM: On your 2006-2009 Uplander, the TCM is located in the engine bay, mounted to the driver’s side (LH) strut tower.
- Disconnect and Remove: Carefully unplug the electrical connectors. Use a socket wrench to remove the bolts holding the old module in place.
- Install the New Module: Mount your new, pre-programmed TCM and securely fasten the bolts. Reconnect the electrical harnesses, ensuring they click into place.
- Final Steps: Reconnect the battery terminal. Start the vehicle and let it idle for a few minutes. While not always necessary, using a basic OBD2 scanner to clear any lingering fault codes is good practice.
Will This Fit My Vehicle?
This T42 Transmission Control Module is a guaranteed fit for the following models:
- 2006-2009 Chevrolet Uplander (Transmission located at LH strut tower)
It is also a direct replacement for a wide range of other General Motors vehicles from 2006-2014, including the Chevrolet Cobalt, HHR, Impala, Monte Carlo; Pontiac G6, Grand Prix; Buick Allure, LaCrosse; and Saturn Vue, among others. It interchanges with part numbers 24239224, 24252114, 24234503, and more.
Frequently Asked Questions
What does ‘VIN Programmed’ mean for me?
It means we flash the module with your vehicle’s specific Vehicle Identification Number (VIN) and the latest GM software before it ships. This ensures it communicates perfectly with your van’s engine computer and other systems right out of the box, saving you from a costly and time-consuming programming session at a dealership.
Is this a difficult part for a DIYer to install?
Not at all. For the Uplander, the TCM is easily accessible on the driver’s side strut tower. With basic hand tools, the swap takes less than 30 minutes. Our pre-programming makes the electronic side of the job completely hassle-free.
Do I need to send my old part back?
No. We do not require a core return. You can keep your old part, which simplifies the process and saves you money on return shipping.
Will this fix a P0700 code?
A P0700 code is a general fault code indicating the TCM has detected a problem. While this module often resolves the root cause (like an internal short that triggers the code), it’s important to confirm there aren’t external wiring or solenoid issues. However, in our experience, a faulty TCM is the most common reason for this code on these vehicles.
What kind of warranty is included?
This module is backed by our one-year warranty, giving you peace of mind and confidence in the quality and reliability of your repair.