If your Chevrolet Express 2500 work van is experiencing harsh shifting, getting stuck in gear, or throwing transmission codes, your downtime is costing you money. As a technician with over two decades of experience, I’ve seen firsthand how a failing Transmission Control Module (TCM) can bring a reliable workhorse to a dead stop. The factory T42 TCM is a known failure point, often leading to erratic behavior that seems impossible to pin down. This isn’t just an inconvenience; it’s a threat to your livelihood.
This is the definitive solution: a high-quality replacement T42 Transmission Control Module, specifically for your 2006-2014 Express 2500 TCM needs. Forget about expensive dealership visits and the hassle of tow trucks. We pre-program this module to your van’s exact Vehicle Identification Number (VIN) before it ships. This means it arrives ready for a true plug-and-play installation, loaded with the latest GM software updates to ensure perfect communication with your vehicle’s powertrain and restore the crisp, reliable shifting you depend on.
Case Study: The “Intermittent” Shifting Nightmare
A local plumbing contractor brought in his 2011 Express 2500, complaining of intermittent, violent 1-2 shifts and occasionally getting stuck in 3rd gear (limp mode) after the van warmed up. He’d already replaced two shift solenoids with no luck. A scan showed a generic P0700 code. In my experience, heat-related electronic failures in these T42 modules are common. The internal circuit boards develop micro-fractures over time. We installed one of our VIN-programmed TCMs, and the van was shifting perfectly within 30 minutes. He was back on the job the same afternoon, saving a full day of lost revenue.
Is Your Express Van Showing These Telltale Signs?
A faulty TCM can manifest in several ways. If you’re noticing any of the following, it’s a strong indicator that your module is the culprit:
- ✔ Harsh, banging shifts or delayed gear engagement.
- ✔ The vehicle is stuck in “limp mode,” usually second or third gear.
- ✔ Your Check Engine Light is on with codes like P0700 (Transmission Control System Malfunction), P0750, or other solenoid-specific faults.
- ✔ The transmission refuses to upshift or downshift correctly.
- ✔ A sudden drop in fuel economy or signs of the transmission overheating.
- ✔ Complete loss of communication with the transmission.
Your 30-Minute Path Back to Work: A Simple Installation Guide
Replacing the 2006-2014 Express 2500 TCM is a straightforward job you can do with basic hand tools. Because our modules are pre-programmed, you eliminate the need for a trip to the dealer for software flashing.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent electrical shorts and help reset the system.
- Locate the Module: On the Express 2500/3500 Van, the TCM is typically mounted in the engine compartment on the right-hand (passenger) side.
- Disconnect and Remove: Carefully unclip the electrical connectors. Be gentle to avoid breaking the plastic tabs. Then, unbolt the module from its mounting bracket.
- Install the New TCM: Bolt the new, pre-programmed module into place and securely reconnect the electrical harnesses. You’ll hear a click as they lock in.
- Final Steps: Reconnect the battery terminal. Start the vehicle and allow it to idle for a few minutes. While not always necessary, using a basic OBD2 scan tool to clear any stored fault codes is good practice. Take the van for a test drive to confirm smooth shifting.
Verified Fitment For These GM Vehicles
This T42 TCM, equivalent to part number 24235340, is a direct replacement for a wide range of GM cars, trucks, and SUVs equipped with 4-speed automatic transmissions like the 4L60E, 4L65E, 4L70E, and 4L80E. Please verify your specific model and year below.
- Chevrolet Express 1500/2500/3500 Van (2006-2014): Transmission; (RH engine compartment)
- GMC Savana 1500/2500/3500 Van (2006-2014): Transmission; (RH engine compartment)
- Chevrolet Silverado & GMC Sierra 1500/2500 (2007-2013): Transmission; (next to battery)
- Chevrolet Tahoe & GMC Yukon (2007-2009): Transmission; (next to battery)
- Chevrolet Avalanche & Suburban (2007-2008): Transmission; (next to battery)
- Chevrolet Impala (2006-2011): Transmission; (lower air cleaner housing)
- Cadillac DTS (2006-2011): Transmission; (RH front engine compartment)
- Buick Lucerne (2006-2011): Transmission; (LH engine compartment)
- Hummer H3 (2008-2010): Transmission; (RH rear engine compartment)
- …and many more models including the Cobalt, HHR, G6, Grand Prix, LaCrosse, and Saab 9-7X.