Restore Peak Performance to Your Workhorse Van
As a technician with over two decades of experience, I know that when your 2006-2014 GMC Savana 1500 Van is down, your business is down. A faulty Transmission Control Module (TCM) is one of the most common, and frustrating, issues I see. It can turn a reliable work vehicle into a liability, with symptoms like erratic shifting, getting stuck in limp mode, or a lit Check Engine light that just won’t go away. This isn’t just an inconvenience; it’s lost time and money.
This T42 Transmission Control Module, a direct replacement for part number 24235754, is the definitive solution. It’s not just a part; it’s a pre-programmed, plug-and-play fix that eliminates the need for expensive dealership visits. We flash the module with your van’s specific VIN and the latest GM software updates before it even ships. This ensures it communicates perfectly with your vehicle’s systems, restoring the crisp, reliable shifting you depend on, right out of the box.
Case Study: The Intermittent Shifting Nightmare
A local contractor brought in his Savana 2500, a cousin to the 1500, with a maddening problem. It would shift perfectly for days, then suddenly start slamming into gear or refuse to shift out of 2nd. He’d already replaced two shift solenoids with no luck. After connecting my scan tool, I saw intermittent communication loss codes with the TCM. Heat soak from the engine compartment was causing the old module’s internal circuits to fail unpredictably. We installed one of our VIN-programmed T42 modules, and the problem was gone for good. It’s a classic failure mode I’ve seen hundreds of times on these GM work vans.
Is Your Savana’s Transmission Showing These Signs?
A failing TCM can mimic other transmission problems. If your van is experiencing any of the following, the TCM is a primary suspect, especially if you’re seeing codes like P0700 or P0750-series solenoid faults.
- ✔ Harsh, banging shifts or delayed gear engagement.
- ✔ Vehicle is stuck in one gear (often called “limp mode”).
- ✔ Check Engine Light or Transmission Warning Light is illuminated.
- ✔ Inability to upshift or downshift, leading to poor acceleration.
- ✔ Noticeable drop in fuel economy.
- ✔ The gear selector indicator on the dash is blank or incorrect.
- ✔ Complete loss of communication with the transmission.
A Straightforward Guide to Installation
For the Savana van, this is one of the easier electronic repairs you can do. You don’t need a vehicle lift or specialized tools, just basic hand tools. The entire process should take less than 30 minutes.
- Safety First: Always disconnect the negative terminal from your van’s battery to prevent electrical shorts and help reset the vehicle’s systems.
- Locate the Module: In most 2006-2014 Savana 1500 vans, the TCM is located in the engine compartment on the right-hand (passenger) side. It’s a silver box with electrical connectors.
- Disconnect and Remove: Carefully unclip the wiring harness connectors. They have locking tabs, so don’t force them. Then, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed TCM into place. Securely reconnect the wiring harnesses, ensuring they click into place.
- Final Steps: Reconnect the battery terminal. Start the engine and let it run for a minute. While the module is pre-programmed, it’s good practice to use a basic OBD2 scan tool to clear any stored diagnostic trouble codes (DTCs) from the computer’s memory.
Verified Vehicle Compatibility
This T42 TCM is a direct fit for a wide range of General Motors vehicles equipped with 4-speed automatic transmissions like the 4L60E, 4L65E, and 4L70E. While this page focuses on the 2006-2014 Savana 1500 TCM, it also fits many others. Please verify your model and part number (interchangeable numbers include 24242391, 24234503, 24252114, and more) before ordering.