Get Your Workhorse Back on the Road: A Reliable Fix for Your Express Van’s Transmission
If your 2006-2014 Chevrolet Express 3500 Van is suffering from erratic shifting, 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 is responsible for every gear change. When it fails, it can bring your work to a halt. This replacement part, number 24240400, is the definitive solution, arriving pre-programmed to your van’s specific VIN for a true plug-and-play repair that eliminates the need for an expensive trip to the dealership.
From the Diagnostic Bay: The Case of the Slipping Work Van
A local contractor brought in his ’11 Express 3500, complaining of intermittent but violent shifts and occasionally getting stuck in 3rd gear—a classic limp mode symptom. He was losing money every day the van was down. A quick scan with my diagnostic tool pulled a P0700 (Transmission Control System Malfunction) and a few solenoid-specific codes. In my 20+ years, I’ve seen this exact pattern hundreds of times with these T42 modules. Heat cycles and vibrations, especially in a hard-working van, eventually cause internal electronic failures. We installed one of our VIN-programmed modules, and he was back on the job site the same afternoon with smooth, predictable shifting. This isn’t just a part; it’s a fast pass back to productivity.
Is Your Express Van Showing These Signs?
- ✔ Harsh, banging shifts or delayed gear engagement.
- ✔ The vehicle is stuck in “limp mode” and won’t shift out of a single gear.
- ✔ 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 noticeable drop in fuel economy or a feeling of slipping between gears.
- ✔ Complete loss of communication with the TCM, preventing diagnostics.
DIY-Friendly Installation in Under 30 Minutes
Replacing the TCM on your Express Van is a straightforward job that most DIY mechanics can complete with basic hand tools. No need to pay for hours of shop labor. For the Express/Savana platform, the module is conveniently located for easy access.
- 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 your Express 3500 Van, the TCM is typically found in the engine compartment on the right-hand (passenger) side.
- Disconnect and Remove: Carefully unplug the electrical connectors. Be gentle with the locking tabs. Then, unbolt the old module from its mounting bracket.
- Install the New TCM: Bolt the new, pre-programmed module into place and securely reconnect the electrical harnesses. You should hear a click as they lock in.
- Final Steps: Reconnect the battery terminal. While the module is plug-and-play, it’s good practice to use a basic scan tool to clear any stored fault codes from the vehicle’s memory. Start the engine and test drive to confirm smooth operation.
Verified Fitment For These GM Models
This T42 TCM is a direct replacement for a wide range of General Motors vehicles equipped with 4-speed automatic transmissions (like the 4L60E, 4L65E, 4L70E, and 4L80E). While this page focuses on the 2006-2014 Express 3500 Van TCM, it also fits the following models. Please verify the location noted for your specific vehicle.
Partial Fitment List:
- 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 IMPALA (2006-2011) – Lower air cleaner housing
- CADILLAC DTS (2006-2011) – RH front engine compartment
- HUMMER H3 (2008-2010) – RH rear engine compartment
- …and many more GM, Buick, Pontiac, and Saturn models.
Frequently Asked Questions
Do I need to have this module programmed by a dealer?
No. We program the module to your vehicle’s VIN before shipping it. This ensures it is ready for installation right out of the box, saving you time and the high cost of dealership programming.
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, making the process hassle-free.
Is this part difficult to install myself?
For most individuals with basic mechanical skills, this is an easy installation that takes less than 30 minutes. The module is typically in an accessible location in the engine bay.
Will this fix a P0700 trouble code?
A P0700 code indicates a general fault within the transmission control system. A failing TCM is a very common cause of this code. Replacing a faulty module with this part will resolve the issue if the TCM was the root cause.
What if I have other transmission problems?
This module corrects electronic faults within the TCM itself. It will not fix mechanical issues inside the transmission, such as worn clutches or a bad torque converter. It’s important to properly diagnose your vehicle’s symptoms before ordering.