End Frustrating Shifting Problems in Your Chevy Express Van
If your 2006-2014 Chevrolet Express 1500 is suffering from harsh shifts, getting stuck in gear, or throwing transmission codes, a failing Transmission Control Module (TCM) is the most likely culprit. As the electronic brain of your automatic transmission, the T42 TCM manages every gear change and torque converter operation. When it fails, it can make your reliable workhorse feel unpredictable and unsafe. This replacement T42 TCM, part number 24234503, is the definitive solution, arriving pre-programmed to your van’s specific VIN for a true plug-and-play fix.
Case Study: A Tricky Diagnosis
A few months back, a local delivery business brought in their 2011 Express 1500. The driver complained of the van suddenly refusing to shift past 2nd gear—classic limp mode. They’d already replaced a shift solenoid at another shop with no luck. After connecting my scan tool, I saw the familiar P0700 (Transmission Control System Malfunction) code, but the solenoid codes were intermittent. In my 20+ years of experience, intermittent electrical faults that don’t point to a single component often trace back to the module itself. We installed one of our VIN-programmed T42 modules. The total time on the lift was under an hour, and the van was back on its delivery route the same afternoon with crisp, smooth shifts. It’s a textbook example of how a failing TCM can mimic other part failures.
Is Your Express Van Showing These Warning Signs?
A bad TCM can cause a host of issues that are often misdiagnosed. Here are the most common symptoms I see in the shop for a failing 2006-2014 Express 1500 TCM:
- ✔ Harsh, banging shifts or delayed gear engagement.
- ✔ Vehicle is stuck in “limp mode” (usually 2nd or 3rd gear) to protect the transmission.
- ✔ The Check Engine Light is on with transmission-related Diagnostic Trouble Codes (DTCs) like P0700, P0750, P0755, or other solenoid-specific codes.
- ✔ Inability to upshift or downshift, leading to poor acceleration and terrible fuel economy.
- ✔ No communication between the scan tool and the TCM.
- ✔ A feeling of the transmission slipping between gears.
A Straightforward Guide to Installation
Replacing the TCM on your Express Van is a job most DIYers can handle in their own driveway in about 30 minutes. Our pre-programming means you skip the expensive trip to the dealership for software flashing.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts and help reset the system.
- Locate the Module: On the 2006-2014 Savana and Express vans, the TCM is typically mounted 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 TCM: Mount the new module securely onto the bracket and plug in the electrical connectors until they click into place.
- Reconnect and Verify: Reconnect the battery terminal. Start the engine and let it idle. Use a standard OBD2 scan tool to clear any stored fault codes from the memory. Test drive the vehicle to confirm smooth shifting has been restored.
Verified Vehicle Compatibility
This T42 TCM is a direct-fit replacement 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 Express 1500 TCM, it is also compatible with the following models. Please verify the location noted for your specific vehicle:
- Chevrolet Express / GMC Savana 1500/2500/3500 (2006-2014): RH engine compartment
- Chevrolet Silverado / GMC Sierra 1500/2500 (2007-2013): Next to battery
- Chevrolet Tahoe / GMC Yukon (2007-2009): Next to battery
- Chevrolet Avalanche 1500 (2007-2008): Next to battery
- Chevrolet Impala / Monte Carlo (2006-2011): Lower air cleaner housing
- Chevrolet Cobalt / HHR (2006-2011): LH engine compartment or strut tower
- Cadillac DTS (2006-2011): RH front engine compartment
- Buick LaCrosse / Allure (2006-2009): Lower air cleaner housing
- Pontiac G6 / Grand Prix (2006-2010): LH strut tower or lower air cleaner housing
- And many more models from Buick, Cadillac, Hummer, Pontiac, Saab, and Saturn.
This part is interchangeable with service numbers: 24242391, 24252114, 24230461, 24234274, 24235340, 24235754, 24238856, 24239224, 24239926, and more.
Frequently Asked Questions
Do I need to do any programming myself?
No. We handle all the programming for you. Simply provide your vehicle’s 17-digit VIN during checkout, and the module will arrive ready for installation with the latest GM software updates. This eliminates the need for expensive dealership tools.
Is this a difficult part to install?
Not at all. For a Chevy Express van, it’s one of the easier electronic modules to replace. It’s located in the engine bay and requires only basic hand tools. Our step-by-step guide above walks you through the process, which typically takes less than 30 minutes.
What is a ‘core charge’ and do you require one?
A core charge is a deposit that other companies charge you until you send back your old, failed part. We do not have a core charge on this item. You can keep your old part or recycle it yourself, saving you time and hassle.
Will this fix a P0700 check engine light code?
A P0700 code is a general fault code indicating the TCM has detected a problem. While this module often resolves the root cause, it’s crucial to ensure the transmission itself and its wiring are in good condition. If the TCM is the source of the fault, replacing it will resolve the code.
How do I know this is the correct part for my van?
This module fits 2006-2014 Express 1500 vans. You can also match the part number on your existing module to 24234503 or any of the interchange numbers listed in our compatibility section to guarantee a perfect fit.