If you rely on your GMC Savana 3500 for work, you know that transmission trouble isn’t just an inconvenience—it’s a direct hit to your bottom line. When your van starts shifting erratically, banging into gear, or gets stuck in limp mode, you need a reliable fix, and you need it fast. As a technician with over two decades of experience, I’ve seen countless work vans sidelined by a faulty Transmission Control Module (TCM). This VIN-programmed T42 TCM is the definitive, no-nonsense solution to get your workhorse back on the road without the costly delays of a dealership visit.
The TCM is the brain of your automatic transmission, controlling every shift and adapting to your driving conditions. When it fails, the symptoms can be confusing and often misdiagnosed as a major mechanical failure. This module, part number 24255280, is engineered to OEM specifications to restore the crisp, predictable shifting your 4L80E or other GM 4-speed automatic transmission was designed to deliver.
Is Your Savana Van Showing These Telltale Signs?
- ✔ Harsh, slamming shifts or unpredictable gear changes.
- ✔ The transmission feels like it’s slipping or hesitating to engage.
- ✔ Your van is stuck in “limp mode,” usually in 2nd or 3rd gear.
- ✔ The Check Engine Light or a transmission warning light is on, with Diagnostic Trouble Codes (DTCs) like P0700, P0750, or other solenoid-related codes.
- ✔ A sudden drop in fuel economy or the transmission seems to be running hotter than usual.
- ✔ Complete loss of communication with the module, preventing shifting altogether.
Case Study: A Tricky Diagnosis
I remember a fleet customer bringing in a 2011 Savana 3500 with a perplexing issue. The van would drive perfectly for 20 minutes, then suddenly start shifting hard and throw a solenoid code. They had already replaced two shift solenoids at another shop with no success. After hooking up my scan tool and monitoring live data, I noticed the TCM was intermittently dropping communication as it warmed up. The internal circuitry was failing under heat soak—a classic TCM failure. We installed a VIN-programmed module just like this one, and the van was back in service the same afternoon. It’s a perfect example of how the 2006-2014 Savana 3500 Van TCM can solve problems that seem purely mechanical.
Get Your Van Back to Work: A Straightforward Installation Guide
For the Savana and Express vans, this is one of the easier module replacements you can do. You don’t need a vehicle lift or specialized transmission tools. The entire process should take less than 30 minutes.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electronic component replacement.
- Locate the TCM: On the 2006-2014 Savana 3500, the TCM is located in the engine compartment on the right-hand (passenger) side. It’s typically mounted near the firewall or inner fender.
- Disconnect and Remove: Carefully unplug the electrical connectors. Press the release tabs firmly to avoid breaking them. Then, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed TCM into place and securely reconnect the electrical harnesses. You should hear a click as they lock in.
- Final Steps: Reconnect the battery terminal. While our programming handles the critical setup, it’s always best practice to use a basic OBD2 scan tool to clear any lingering fault codes from the system’s memory. Start the vehicle and test drive to confirm smooth shifting.
Verified Fitment for Your General Motors Vehicle
This T42 TCM is a direct replacement for a wide range of GM vehicles. While this page focuses on the 2006-2014 Savana 3500 Van TCM, it is also compatible with the following models. Please verify the location noted for your specific vehicle.
- SAVANA 3500 VAN 06-14 Transmission; (RH engine compartment)
- EXPRESS 3500 VAN 06-14 Transmission; (RH engine compartment)
- SAVANA 2500 VAN 06-14 Transmission; (RH engine compartment)
- EXPRESS 2500 VAN 06-14 Transmission; (RH engine compartment)
- SAVANA 1500 VAN 06-14 Transmission; (RH engine compartment)
- EXPRESS 1500 VAN 06-14 Transmission; (RH engine compartment)
- SIERRA & SILVERADO (1500/2500) 07-13 Transmission; (next to battery)
- TAHOE & YUKON 07-09 Transmission; (next to battery)
- SUBURBAN & YUKON XL 1500 07-08 Transmission; (next to battery)
- COLORADO & CANYON 08-12 Transmission; (RH rear engine compartment)
- HUMMER H3 08-10 Transmission; (RH rear engine compartment)
- IMPALA 06-11 Transmission; (lower air cleaner housing)
- COBALT / G5 / G6 06-10 Transmission; (LH strut tower)
- And many more GM, Pontiac, Buick, Saturn, Saab, and Cadillac models. Please see the full fitment list for details.
What does ‘VIN Programmed’ actually mean for me?
What does ‘VIN Programmed’ actually mean for me?
It means this module arrives at your door ready for installation. We flash it with your vehicle’s specific Vehicle Identification Number (VIN) and the latest GM software updates. This ensures it communicates perfectly with your engine computer and other systems, avoiding the need for a separate, expensive programming service at a dealership.
Is there a core charge for my old TCM?
No, there is no core charge. You are not required to send your old, faulty module back to us, which saves you time and return shipping costs.
Do I need any special tools for this installation?
No special tools are required. A basic socket set to remove the mounting bolts and your hands to disconnect the electrical plugs are all you need. A scan tool is recommended to clear old codes post-installation but is not strictly necessary for the module to function.
Will this fix a P0700 trouble code?
A P0700 code is a general fault request from the TCM to the Engine Control Module (ECM) to turn on the check engine light. A faulty TCM is a very common cause of this code. While this module will resolve the issue if the TCM itself is the root cause, you should always diagnose any other specific codes (like P0750-P0758 for solenoids) that are present alongside it.
What if I have questions during installation?
We provide expert support. If you’re unsure about a step or have a question about your specific vehicle, our team of experienced technicians is here to help guide you through the process.