If your 2006-2014 Chevrolet Express 1500 Van is suffering from erratic shifting, getting stuck in gear, or throwing transmission codes, you’re not just dealing with an annoyance—you’re dealing with a potential breakdown waiting to happen. As a mechanic with over two decades of experience under the hood, I’ve seen countless work vans and family haulers sidelined by a faulty Transmission Control Module (TCM). The TCM is the brain of your automatic transmission, and when it fails, it can cause chaos. This T42 TCM, a direct replacement for part number 24238856, is the reliable, straightforward solution you need.
The biggest hurdle with replacing a TCM has always been the expensive and time-consuming trip to the dealership for programming. We eliminate that step entirely. We pre-program this module to your vehicle’s specific VIN before it ships, ensuring it’s ready for immediate installation right out of the box. This means it communicates perfectly with your van’s Engine Control Module (ECM) and other systems, restoring the precise, smooth shifting you expect from your 4L60E or 4L80E series transmission.
From the Diagnostic Bay
I remember a local delivery company brought in their 2011 Express 1500. The driver complained of intermittent, violent shifts and the van occasionally going into limp mode, but by the time it got to the shop, it would behave normally. There were no hard codes, just a stored P0700 (Transmission Control System Malfunction). After checking the wiring and fluid, we suspected the TCM was failing under heat soak. Instead of a costly diagnostic goose chase, we recommended a VIN-programmed module. They installed this exact part in their parking lot in under 20 minutes. The van was back in service the same day, and they’ve since replaced the modules in their entire fleet as preventative maintenance. It’s a testament to how a simple, reliable part can save a business time and money.
Is Your Express Van Showing These Symptoms?
- âś” Harsh, slamming shifts or delayed gear engagement.
- âś” The vehicle is stuck in a single gear (often called “limp mode”).
- âś” Check Engine Light or Transmission Warning Light is on.
- âś” Diagnostic Trouble Codes (DTCs) are present, such as the generic P0700 or specific solenoid codes like P0750, P0753, P0758.
- âś” Unexplained drops in fuel economy or a transmission that seems to be overheating.
- âś” Complete loss of communication with the transmission module.
A Straightforward Guide to Your 2006-2014 Express 1500 TCM Installation
This is a job most DIYers can handle with basic tools. On the Express and Savana vans, the TCM is typically located in the engine compartment on the right-hand (passenger) side, making it easily accessible.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts and to help reset the onboard systems.
- Locate the TCM: On your Express Van, find the module on the RH side of the engine bay. It will have several large electrical connectors attached.
- Disconnect and Remove: Carefully unclip the wiring harness connectors. Press the release tabs firmly. 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. While the module is plug-and-play, it’s good 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 Vehicle Compatibility
This T42 TCM is a guaranteed fit for a wide range of General Motors vehicles equipped with 4-speed automatic transmissions. While this page focuses on the 2006-2014 Express 1500 TCM, it is also a direct replacement for the following models. Please verify the location noted for your specific vehicle:
- Chevrolet: Avalanche (07-08), Cobalt (06-10), Colorado (08-12), Express/Savana Vans (06-14), HHR (06-11), Impala (06-11), Monte Carlo (06-07), Silverado (07-13), SSR (05-06), Tahoe (07-09), Trailblazer (06-09)
- GMC: Canyon (08-12), Envoy (06-09), Sierra (07-13), Yukon (07-09)
- Buick: Allure (06-09), LaCrosse (06-09), Lucerne (06-11), Rainier (06-07), Rendezvous (06-07)
- Pontiac: G5 (07-10), G6 (06-10), Grand Prix (06-08), Pursuit (06), Montana (06-09)
- Cadillac: DTS (06-11)
- Saturn: Aura (07-09), Ion (06-07), Vue (07-10)
- Hummer: H3 (08-10)
- Saab: 9-7X (06-09)
This part interchanges with service numbers: 24252114, 24234503, 24230461, 24234274, 24235340, 24235754, 24238856, 24239224, 24239926, and many more.
Frequently Asked Questions
Do I need to take my van to the dealer after installing this?
No. This module comes fully programmed to your vehicle’s VIN. It is a true plug-and-play solution, saving you the time and expense of a dealership visit.
Is this a difficult part to install myself?
Not at all. For a Chevy Express van, the location on the passenger side of the engine bay is very accessible. With basic hand tools, most people can complete the replacement in under 30 minutes.
What is a core charge? Do I need to send my old part back?
There is no core charge for this part. You can keep your old module or dispose of it yourself without any hassle or extra fees.
Will this fix a P0700 trouble code?
A P0700 code is a generic code indicating the TCM has detected a fault. Often, a failing TCM is the root cause. Replacing the module with this pre-programmed unit will resolve the issue if the module itself is the problem.
What happens if I order the wrong part?
We program the module based on the VIN you provide at checkout, which ensures compatibility. Our team of experts is also available to help you confirm fitment before you buy to make sure you get the right part the first time.