Get Your Work Van Back on the Job with a Reliable Transmission Fix
If your 2006-2014 Chevrolet Express 2500 Van is suffering from erratic shifting, getting stuck in gear, or has the transmission warning light on, the problem is often not the transmission itself, but a faulty Transmission Control Module (TCM). As a mechanic with over two decades of experience, I’ve seen countless work vans sidelined by this issue. A non-shifting van means lost time and money. This T42 TCM, part number YNXS, is the direct-fit, reliable solution to get your Express van running smoothly again, without the costly trip to the dealership.
This isn’t just a part; it’s a complete solution. We pre-program the module to your van’s specific Vehicle Identification Number (VIN) before it ships. This means it arrives ready for a true plug-and-play installation. It will communicate seamlessly with your van’s Engine Control Module (ECM) and other systems, restoring precise shift points, proper torque converter lockup, and accurate diagnostic reporting for the 4L80E or 4L85E automatic transmission.
A Technician’s Notebook: The Misleading P0700 Code
A customer brought in his Express 2500 cargo van, convinced he needed a full transmission rebuild. The van was stuck in 3rd gear (limp mode), and his local shop quoted him thousands. He had a generic P0700 code, which simply means ‘Transmission Control System Malfunction.’ After a quick scan with a proper tool, I pulled the specific codes from the TCM itself—multiple solenoid circuit faults. In my shop, I’ve diagnosed hundreds of these T42 module failures. The internal drivers for the solenoids fail from heat and vibration over time. We swapped in a VIN-programmed TCM, cleared the codes, and had his van shifting perfectly in under an hour. He saved a fortune and got his work vehicle back the same day.
Is Your Express Van Showing These Symptoms?
- ✔️ Harsh, banging shifts or delayed gear engagement.
- ✔️ Vehicle is stuck in one gear (often 2nd or 3rd) and won’t shift up or down.
- ✔️ Check Engine Light or Transmission Warning Light is illuminated.
- ✔️ Diagnostic Trouble Codes (DTCs) are present, such as P0700, P0750, P0753, P0758, or other solenoid-related faults.
- ✔️ A sudden drop in fuel economy or a sensation of the transmission slipping.
- ✔️ Complete loss of communication with the TCM, preventing diagnostics.
A Straightforward Installation Guide for Your Express Van
Replacing the 2006-2014 Express 2500 TCM is a job most DIYers or any professional mechanic can handle in about 30 minutes with basic hand tools. No complex procedures are required.
- Safety First: Disconnect the negative terminal from your van’s battery to prevent any electrical shorts.
- Locate the Module: On the Express 2500, the TCM is typically found in the engine compartment on the right-hand (passenger) side.
- Disconnect and Remove: Carefully unplug the electrical connectors. Press the release tabs firmly. Then, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new VIN-programmed TCM into place and securely reconnect the electrical harnesses. Ensure they click into place.
- Final Steps: Reconnect the battery terminal. While the module is plug-and-play, it’s best practice to use a standard OBD2 scan tool to clear any old fault codes stored in other modules. Start the van and test drive to confirm smooth shifting.
Guaranteed Fitment for Your General Motors Vehicle
This T42 TCM is a direct replacement for part number YNXS and is compatible with a wide range of GM vehicles equipped with 4-speed automatic transmissions. While this page focuses on the 2006-2014 Express 2500 TCM, it also fits the following models:
- Chevrolet Express / GMC Savana 1500, 2500, 3500 (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 Impala (2006-2011): Transmission; (lower air cleaner housing)
- Hummer H3 (2008-2010): Transmission; (RH rear engine compartment)
- Cadillac DTS (2006-2011): Transmission; (RH front engine compartment)
- …and many other GM cars, trucks, and SUVs from 2006-2014. Please verify your part number or contact us with your VIN.
Frequently Asked Questions
Do I need to take my van to the dealer for programming?
No. This module is delivered to you pre-programmed to your vehicle’s VIN. The installation is plug-and-play, saving you time and money on dealer programming fees.
Is there a core charge for my old part?
Absolutely not. There is no core charge, so you don’t have to worry about the cost or hassle of sending your old, faulty module back to us.
What tools do I need for installation?
You’ll only need basic hand tools, such as a socket set and ratchet, to remove the mounting bolts and disconnect the battery. No special equipment is required.
Will this fix a P0700 trouble code?
A P0700 code is a general fault indicator. This TCM often resolves the underlying issue causing the P0700, such as failed solenoid circuits. After installation, all codes should be cleared to verify the fix.
What is the warranty on this TCM?
This part comes with a one-year warranty, giving you peace of mind that you’re installing a quality, reliable component in your vehicle.