If your 2006-2014 GMC Savana 1500 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 firsthand how a faulty Transmission Control Module (TCM) can bring a reliable workhorse to a halt. Erratic shifting, getting stuck in gear, or a persistent check engine light are more than just annoyances; they’re signs that the brain of your transmission is failing. This T42 TCM, part number 24243921, is the definitive, no-hassle solution to get your van back on the road and earning its keep.
The biggest challenge with replacing electronic modules has always been the expensive and time-consuming trip to the dealership for programming. We eliminate that step entirely. This module arrives at your door pre-programmed to your van’s specific Vehicle Identification Number (VIN). This ensures it communicates perfectly with your vehicle’s engine computer and other systems right out of the box. It’s a true plug-and-play fix designed for the professional mechanic who values efficiency and the DIYer who wants to save hundreds on dealer fees.
Case Study: A Tricky Diagnosis
A local plumbing contractor brought in his ’09 Savana 1500. The complaint was intermittent harsh 1-2 shifts and occasionally getting stuck in 3rd gear (limp mode), but only after the van was fully warmed up. He’d already replaced two shift solenoids with no change. After scanning, I found a P0750 code stored, but live data was inconclusive at first. Based on experience with these 4L60E/4L80E platforms, I suspected the TCM was failing internally under heat. We installed one of our pre-programmed T42 modules. The entire job took less than 25 minutes in the bay. The contractor was back on the road the same afternoon, and a follow-up call confirmed all shifting issues were gone. This is a classic example of how a failing 2006-2014 Savana 1500 TCM can mimic mechanical faults.
Is Your Savana Exhibiting These Transmission Faults?
A failing TCM can cause a wide range of confusing symptoms. If your van is showing any of the following signs, a faulty module is the most likely culprit:
- âś” Harsh, banging, or delayed gear shifts, especially when cold or hot.
- âś” The vehicle is stuck in a single gear (often called “limp mode”) and won’t shift up or down.
- âś” Check Engine Light or Transmission Warning Light is illuminated with Diagnostic Trouble Codes (DTCs) like P0700, P0750, P0755, or other solenoid-related codes.
- âś” Inability to engage drive or reverse, or a long delay before engagement.
- âś” Poor fuel economy and a feeling of sluggish performance.
- âś” Complete loss of communication with the transmission module, preventing diagnostics.
Simple Installation for Your Savana Van
You don’t need a professional lift or complex tools to replace the 2006-2014 Savana 1500 TCM. It’s designed for a straightforward swap that you can complete in your driveway in under 30 minutes.
- 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 Module: On the Savana and Express vans, the TCM is typically found in the engine compartment on the right-hand (passenger) side.
- Disconnect and Remove: Carefully unplug the electrical connectors. Press the release tabs firmly to avoid breaking them. Then, unbolt the old module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed TCM into place and securely reconnect the electrical harnesses. You should hear a ‘click’ as they lock in.
- Final Steps: Reconnect the negative battery terminal. Start the vehicle and allow it to idle for a few minutes. If you have a basic OBD2 scanner, it’s good practice to clear any old fault codes from the system.
Verified Vehicle Compatibility
This T42 Transmission Control Module is a direct replacement for part number 24243921 and is interchangeable with a wide range of other service numbers. It fits numerous GM vehicles equipped with 4-speed automatic transmissions (4L60E, 4L65E, 4L70E, 4L80E). While this page is focused on the 2006-2014 Savana 1500 TCM, it also fits:
- âś” Chevrolet Express, Silverado, Tahoe, Impala, HHR, Cobalt
- âś” GMC Sierra, Yukon, Envoy, Canyon
- âś” Cadillac DTS, Buick LaCrosse, Lucerne
- âś” Pontiac G6, Grand Prix
- âś” And many more models listed in the fitment data.
Frequently Asked Questions
Why is VIN programming so important?
VIN programming loads your vehicle’s specific software, including shift points, torque converter strategies, and communication protocols. Without it, a new TCM won’t work correctly, leading to shifting problems or a no-start condition. Our pre-programmed module saves you a trip to the dealer and ensures flawless performance.
Is this a difficult part to install myself?
Not at all. For most vehicles, including the Savana van, this is one of the easier electronic components to replace. It’s located in the engine bay and requires only basic hand tools. Our step-by-step guide makes it a simple, sub-30-minute job for most DIYers.
Will this fix a P0700 trouble code?
A P0700 code is a generic fault code indicating the TCM has detected a problem and requested the check engine light. This module often resolves the underlying issue (like a faulty solenoid driver) that caused the P0700 code in the first place. After installation, clearing the codes should resolve the light.
Do I need to send my old part back?
No. We do not require a core charge for this part. You can keep your old module or dispose of it, making the transaction simple and hassle-free.
What if I have questions during installation?
We’re here to help. Our team of experts has hands-on experience with these parts and can provide support to ensure your repair is successful. Your purchase is backed by our expertise and a one-year warranty.