Is Your GMC Savana 3500 Shifting Erratically?
If your 2006-2014 GMC Savana 3500 is experiencing harsh shifting, getting stuck in gear, or throwing transmission-related check engine light codes, a failing Transmission Control Module (TCM) is the most likely culprit. The TCM is the electronic brain of your automatic transmission, responsible for orchestrating every gear change, managing torque converter lockup, and ensuring the smooth, efficient operation you rely on for your work van or passenger vehicle. When it fails, it can lead to frustrating performance issues, poor fuel economy, and even leave you stranded.
This genuine OEM-quality T42 Transmission Control Module, part number 24256960, is the definitive solution to restore your vehicle’s transmission performance. We take the guesswork and dealership hassle out of the equation by pre-programming the module to your vehicle’s specific VIN. This ensures that it arrives ready for a plug-and-play installation, loaded with the latest GM software updates for optimal function right out of the box.
From the Diagnostic Bay
We had a 2011 Savana 3500 work van come into the shop that was a nightmare for the owner. It would randomly slam into gear, sometimes refusing to shift past 2nd gear (limp mode), making highway driving impossible. The driver was seeing a P0700 code and a few solenoid-specific codes. After confirming the wiring and solenoids were good, we pinpointed the TCM. Instead of sending him to a dealership for a costly replacement and programming, we installed one of our VIN-programmed T42 modules. In under 30 minutes, the van was back on the road, shifting like it just rolled off the factory floor. The owner was back in business the same day, saving significant time and money.
Diagnosing Your Failing Savana 3500 TCM
A faulty TCM can manifest in several ways, often starting as intermittent issues that worsen over time. Recognizing these symptoms early can prevent further damage to your transmission’s mechanical components. This module is the correct fix for a wide range of problems affecting not only the Savana but also the Chevrolet Express, Silverado, Tahoe, and dozens of other GM vehicles equipped with 4-speed automatic transmissions like the 4L60E, 4L65E, and 4L80E.
Common Symptoms of a Bad T42 TCM
- ✔ Harsh or Delayed Shifting: Experiencing abrupt, jerky gear changes or a noticeable lag when the transmission shifts up or down.
- ✔ Stuck in Limp Mode: The vehicle refuses to shift out of a single gear (typically 2nd or 3rd) to protect the transmission from further damage.
- ✔ Illuminated Warning Lights: The Check Engine Light or a specific transmission warning light is on. Common diagnostic trouble codes (DTCs) include P0700, P0750, P0753, P0758, and other solenoid circuit codes.
- ✔ Inability to Shift: The transmission may not upshift or downshift at all, leading to poor acceleration and high RPMs.
- ✔ Poor Fuel Economy: Inefficient shifting and torque converter operation cause the engine to work harder, significantly increasing fuel consumption.
- ✔ Erratic Instrument Cluster Behavior: In some cases, a failing TCM can cause the gear indicator (PRNDL) or other gauges to behave erratically.
Plug-and-Play VIN Programming: The Key Benefit
The single biggest challenge when replacing a modern vehicle module is programming. This T42 TCM is professionally programmed to your van’s VIN before it ships. This means it communicates perfectly with your vehicle’s Engine Control Module (ECM) and other systems from the moment you install it. You bypass the expensive programming fees and scheduling delays at a dealership, making this a straightforward DIY or independent shop repair.
Installation is simple:
- Disconnect the vehicle’s battery.
- Locate the existing TCM. In a Savana or Express van, it’s typically found in the engine compartment on the right-hand (passenger) side.
- Carefully unplug the electrical connectors and unbolt the old module.
- Mount the new module, reconnect the connectors, and reconnect the battery.
- Use a standard OBD2 scan tool to clear any stored DTCs.
With no core charge, you can keep your old part without the hassle of returns. This module is a direct replacement for numerous service numbers, including 24252114, 24234503, 24230461, and many more, ensuring broad compatibility.
Frequently Asked Questions
What does ‘VIN Programmed’ mean for my Savana?
It means we load the module with your specific vehicle’s factory software and calibration files using your Vehicle Identification Number (VIN). This makes the part fully compatible with your van’s engine, options, and transmission type, eliminating the need for any additional programming after installation.
Will I need a dealership to install this module?
No. Because the module arrives pre-programmed, installation is a simple plug-and-play process. A confident DIYer or any competent mechanic can complete the job in under an hour, saving you hundreds in dealership labor and programming fees.
Is this TCM compatible with my 4L80E transmission?
Yes, this T42 TCM is the correct controller for GM vehicles from this era equipped with the 4L60E, 4L65E, 4L70E, and the heavy-duty 4L80E 4-speed automatic transmissions. It is the specified part for 2006-2014 Savana and Express vans.
What happens if I don’t replace a failing TCM?
Continuing to drive with a faulty TCM can lead to severe and costly mechanical damage to your transmission. Poor shift timing and incorrect line pressure can burn out clutches and damage internal components, potentially requiring a complete transmission rebuild.
How do I know this is the exact right part for my van?
This part fits 2006-2014 GMC Savana 3500 vans. You can also verify by matching the part number 24256960 or one of the interchangeable service numbers listed in the description to your existing module. Providing your VIN at checkout guarantees we program it correctly for a perfect fit.