Get Your Workhorse Van Back in Service
If your 2006-2014 GMC Savana 2500 Van is suffering from erratic shifting, getting stuck in gear, or throwing transmission codes, the culprit is often a failing Transmission Control Module (TCM). As the electronic brain of your automatic transmission, the T42 TCM governs every shift point, torque converter clutch engagement, and line pressure adjustment. When it fails, it can sideline your vehicle and disrupt your work. This direct-replacement T42 TCM, part number 24239926, is the reliable, cost-effective solution to restore your van’s performance and get you back on the road without a costly trip to the dealership.
Case Study: A Tricky Diagnosis
I had a 2011 Savana 2500 work van come into my bay last month. The owner, a local plumber, was frustrated. His van would occasionally slam into gear, and twice it had gone into ‘limp mode’ (stuck in 3rd gear) on the highway, forcing him to pull over. He was getting a generic P0700 (Transmission Control System Malfunction) code, but no specific solenoid codes. He feared a complete transmission rebuild, which would cost him thousands and days of lost work. After checking the basics—fluid level and condition—we tested the TCM. Sure enough, it was failing intermittently. We installed this exact VIN-programmed T42 module. The entire job took less than 25 minutes. The van’s shifting was immediately smooth and precise. He was back on the job the same afternoon, having avoided a massive repair bill and downtime. These modules are a common failure point, and a pre-programmed unit is the fastest, most reliable fix.
Is Your Savana Van Showing These Telltale Signs?
A faulty TCM can manifest in several ways. If you’re experiencing any of the following, it’s a strong indicator that your module needs replacement. Over my 20+ years, these are the most common symptoms I’ve seen linked directly to a failing 2006-2014 Savana 2500 TCM.
- ✔ Harsh, banging shifts or delayed gear engagement.
- ✔ The vehicle is stuck in one gear (often called limp mode).
- ✔ Check Engine Light or Transmission Warning Light is illuminated.
- ✔ Diagnostic Trouble Codes (DTCs) are present, especially P0700, P0750-P0758, or other solenoid-related faults.
- ✔ Failure to upshift or downshift properly as you accelerate or slow down.
- ✔ A noticeable decrease in fuel economy.
- ✔ Complete loss of communication with the TCM, preventing diagnostics.
A Straightforward Guide to Installation
One of the best features of this module is its simple, plug-and-play installation. Because we program it to your vehicle’s VIN before shipping, you don’t need any special scan tools or a trip to the dealer for programming. For the GMC Savana, the process is especially easy.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts and to help reset the system.
- Locate the Module: On the 2006-2014 Savana vans, the TCM is conveniently located in the engine compartment on the right-hand (passenger) side. It’s typically mounted to the firewall or inner fender.
- 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, pre-programmed TCM into place. Securely plug in the electrical connectors until they click.
- Final Steps: Reconnect the battery terminal. Start the vehicle and let it idle for a minute. It’s a good practice to use a basic code reader to clear any lingering fault codes from the computer’s memory. Test drive to confirm smooth shifting.
Verified Vehicle Compatibility
While this is the correct part for the 2006-2014 Savana 2500 TCM replacement, this versatile T42 module also fits a wide range of other General Motors vehicles. Please verify your specific model and part number. This module is interchangeable with part numbers 24252114, 24234503, 24239926, and more.
- Chevrolet: Silverado, Tahoe, Suburban, Express, Impala, Cobalt, HHR, Avalanche
- GMC: Sierra, Yukon, Savana, Envoy, Canyon
- Buick: LaCrosse, Lucerne, Allure, Rainier
- Cadillac: DTS
- Pontiac: G6, G5, Grand Prix
- Saturn: Vue, Aura, Ion
- Hummer: H3
- Saab: 9-7X
Frequently Asked Questions
What does ‘VIN Programmed’ mean for me?
It means we load your vehicle’s specific Vehicle Identification Number (VIN) and the latest GM software onto the module before we ship it. This ensures it communicates perfectly with your van’s engine computer and other systems right out of the box, eliminating the need for expensive dealership programming.
Is this a difficult part to install myself?
Not at all. For a DIYer with basic hand tools, this is a very straightforward job that typically takes less than 30 minutes. The location on the Savana van is easily accessible in the engine bay.
Will this fix a P0700 trouble code?
A P0700 code is a general fault code indicating the TCM has detected a problem. While this module often resolves the root cause that triggers a P0700, you should always diagnose any other specific codes (like for a particular solenoid) that may be present. In many cases where the TCM itself is the failure, this part is the direct fix.
Do I need to send my old TCM back?
No, there is no core charge for this part. You can keep your old module or dispose of it, saving you the time and hassle of a return shipment.
How do I know if the TCM is the problem and not the transmission itself?
TCM failures are often electrical in nature, causing erratic behavior, communication loss, or multiple solenoid codes at once. Internal transmission failures are typically more mechanical, often accompanied by noises like whining or grinding, slipping that gets worse with heat, or burnt-smelling fluid. If the symptoms are intermittent and electrical, the TCM is a prime suspect.