If your Chevrolet Express 3500 work van is sidelined with transmission problems, you’re not just inconvenienced—you’re losing money. As a technician with over two decades of experience, I’ve seen countless fleet vehicles and daily drivers crippled by a failing Transmission Control Module (TCM). Symptoms like harsh, unpredictable shifting, getting stuck in limp mode, or a persistent check engine light can bring your operations to a halt. This T42 TCM, part number 24234274, is the definitive, reliable solution to get your van back on the road and working as hard as you do.
This isn’t just a replacement part; it’s a complete, ready-to-install fix. We pre-program each module to your van’s specific Vehicle Identification Number (VIN) before it ships. This critical step ensures seamless communication with your vehicle’s powertrain and eliminates the need for expensive programming at a dealership. It directly addresses the root cause of many electronic transmission faults, restoring the precise, smooth shifting you depend on. For the professional mechanic or the savvy fleet owner, this means less diagnostic guesswork and faster turnaround times.
Is Your Express Van Showing These Signs?
A faulty TCM can manifest in various ways. In my shop, these are the most common complaints that point directly to a failing module. If you’re experiencing any of these, a new TCM is the likely solution.
- ✔ Harsh, banging shifts or delayed gear engagement.
- ✔ The vehicle is stuck in a single gear (limp mode), often 2nd or 3rd.
- ✔ Check Engine Light or Transmission Warning Light is on with codes like P0700, P0750, or other solenoid-related faults.
- ✔ Complete loss of upshifting or downshifting capabilities.
- ✔ Poor fuel economy and a feeling of sluggish performance.
- ✔ Intermittent loss of communication with the scanner or other modules.
A Straightforward Guide to Installation
Replacing the 2006-2014 Express 3500 TCM is a job most DIYers or any professional can handle in under 30 minutes with basic tools. The key is its location and the pre-programming that makes it plug-and-play.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery to prevent electrical shorts and help reset the system.
- Locate the Module: On the Express and Savana vans, the TCM is typically found in the engine compartment on the right-hand (passenger) side. Check near the main fuse block or firewall.
- Disconnect and Remove: Carefully unclip the wiring harness connectors. Press the release tabs firmly. Then, unbolt the old module from its mounting bracket.
- Install the New TCM: Mount the new, pre-programmed module in place and securely tighten the bolts. Reconnect the wiring harnesses, ensuring they click into place.
- Final Steps: Reconnect the battery terminal. While our programming handles the critical setup, it’s best practice to use a basic scan tool to clear any stored Diagnostic Trouble Codes (DTCs) from the vehicle’s memory. Start the engine and test drive to confirm smooth operation.
Case Study: The “Haunted” Work Van
A local contractor brought in his 2011 Express 3500, complaining of intermittent, violent shifts and occasional limp mode that would vanish after restarting the van. He’d already replaced two shift solenoids with no luck. After connecting my scanner, I saw communication dropouts with the TCM. Instead of a mechanical issue, the module itself was failing internally, especially when hot. We installed one of our VIN-programmed T42 modules, and the problem was solved instantly. It saved him from a costly, and unnecessary, transmission rebuild.
Verified Vehicle Compatibility
This T42 TCM is engineered for a wide range of General Motors vehicles equipped with 4-speed automatic transmissions like the 4L60E, 4L65E, and 4L80E. While it’s a direct-fit solution for the 2006-2014 Express 3500 TCM requirement, it also fits many other trucks, vans, and SUVs, including the Chevrolet Silverado, Tahoe, Suburban; GMC Sierra, Yukon, Savana; and Cadillac DTS, among others. It is interchangeable with numerous part numbers, including 24252114, 24234503, and 24230461. Please use the fitment finder tool on this page to confirm an exact match for your vehicle.
Frequently Asked Questions
Do I need to get this module programmed by a dealer?
No. This is the biggest benefit of our service. We program the module to your vehicle’s VIN before shipping, so it arrives ready for installation. This saves you time and the typical $100-$200 dealer programming fee.
Is this part difficult to install myself?
Not at all. For most models, it’s a simple bolt-off, bolt-on process located in the engine bay that requires only basic hand tools and about 30 minutes of your time. No special equipment is needed.
What is a core charge? Do I need to send my old part back?
There is no core charge for this module. You can keep your old part, so there’s no hassle with return shipping or waiting for a refund.
Will this fix a P0700 trouble code?
A P0700 code is a general fault request from the TCM to the main engine computer (ECM) to turn on the check engine light. While this part often resolves the underlying issue causing the P0700, you should scan for more specific P-codes (like P0751, P0756, etc.) to confirm the diagnosis.
What kind of warranty is included?
This module is backed by our one-year, hassle-free warranty, giving you peace of mind for your repair.