If your 2006-2014 GMC Savana 3500 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 a workhorse vehicle, any downtime can mean lost business. This replacement T42 TCM, service part number 24234503, is the definitive solution to restore your van’s reliability and performance without the high cost and hassle of a dealership visit.
Over my 20 years in the shop, I’ve seen countless commercial vans come in with these exact issues. The driver reports harsh bangs into gear or a complete loss of power when the transmission goes into ‘limp mode.’ The problem is almost always electronic, not mechanical. This module is the brain of your automatic transmission (like the 4L80E or 4L85E found in these vans), controlling every shift point and torque converter operation. A faulty one can mimic a catastrophic transmission failure, but the fix is surprisingly simple with the right part.
Is Your Savana Van Exhibiting These Symptoms?
A failing TCM can cause a cascade of issues. If you’re experiencing any of the following, it’s a strong indicator that your module needs replacement. A faulty 2006-2014 Savana 3500 TCM is a common point of failure, but easily resolved.
- ✔ Harsh, delayed, or unpredictable gear shifts.
- ✔ Vehicle is stuck in a single gear (often 2nd or 3rd) and will not shift up or down.
- ✔ The Check Engine Light or Transmission Warning Light is illuminated on your dash.
- ✔ Diagnostic Trouble Codes (DTCs) are present, such as the general P0700 or specific solenoid codes like P0750, P0753, P0758.
- ✔ A sudden drop in fuel economy or the transmission overheating.
- ✔ No communication with the TCM when checked with a scan tool.
Case Study: The Fleet Van Fix
A local contractor brought in one of his Savana 3500 work vans complaining of it being stuck in 3rd gear. His driver was stranded, and the van was useless. His scan tool showed a P0700 code. He was worried he needed a full transmission rebuild, which would have cost thousands and taken the van out of service for a week. After a quick diagnostic, I confirmed the TCM was the issue. Instead of sending him to the dealer for a new module and programming, we provided one of these pre-programmed units. He installed it himself in the shop parking lot in under 20 minutes. The van was back on the road that same afternoon, and he ordered two more for his other vans as preventative maintenance. That’s the power of a plug-and-play solution.
A Straightforward Guide to Installation
One of the best features of this module is its simple, direct-fit installation. You don’t need specialized tools or a trip to the dealership. For your Savana van, the process is particularly easy.
- Safety First: Before you begin, disconnect the negative terminal from your vehicle’s battery. This prevents any electrical shorts and helps reset the vehicle’s computer system.
- Locate the Module: On the 2006-2014 Savana 2500/3500 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.
- Remove the Old Unit: 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 and securely reconnect the electrical harnesses. You should hear a ‘click’ as they lock in.
- Final Steps: Reconnect the battery terminal. Start the vehicle and let it idle for a few minutes. If you have a basic scan tool, it’s good practice to perform a final clear of any stored codes. Take the van for a test drive to confirm smooth shifting has been restored.
Verified Vehicle Compatibility
This T42 Transmission Control Module is a direct replacement for part number 24234503 and is interchangeable with many other service numbers. It fits a wide range of GM vehicles, ensuring broad compatibility. While this page focuses on the 2006-2014 Savana 3500 TCM, it also fits the following models:
- GMC: Savana 1500/2500/3500 (06-14), Sierra 1500/2500 (07-13), Yukon (07-09), Envoy (06-09), Canyon (08-12)
- Chevrolet: Express 1500/2500/3500 (06-14), Silverado 1500/2500 (07-13), Tahoe (07-09), Suburban 1500 (07-08), Avalanche 1500 (07-08), Cobalt (06-10), HHR (06-11), Impala (06-11), Malibu (06-10), Monte Carlo (06-07), Colorado (08-12)
- Buick: LaCrosse (06-09), Lucerne (06-11), Allure (06-09), Rainier (06-07)
- Cadillac: DTS (06-11)
- Pontiac: G5/G6 (06-10), Grand Prix (06-08)
- Saturn: Vue (07-10), Aura (07-09), Ion (06-07)
- Hummer: H3 (08-10)
- Saab: 9-7X (06-09)
What does ‘VIN Programmed’ mean for me?
What does ‘VIN Programmed’ mean for me?
It means we flash the module with your vehicle’s specific Vehicle Identification Number (VIN) and the latest GM software before we ship it. This ensures it communicates perfectly with your van’s other computers (like the ECM and BCM) right out of the box. You get optimal performance without needing a dealership’s expensive programming service.
Do I really not need to take this to a dealer?
What does ‘VIN Programmed’ mean for me?
It means we flash the module with your vehicle’s specific Vehicle Identification Number (VIN) and the latest GM software before we ship it. This ensures it communicates perfectly with your van’s other computers (like the ECM and BCM) right out of the box. You get optimal performance without needing a dealership’s expensive programming service.
Where is this module located on my 2011 Savana 3500?
What does ‘VIN Programmed’ mean for me?
It means we flash the module with your vehicle’s specific Vehicle Identification Number (VIN) and the latest GM software before we ship it. This ensures it communicates perfectly with your van’s other computers (like the ECM and BCM) right out of the box. You get optimal performance without needing a dealership’s expensive programming service.
Will this part fix my check engine light and P0700 code?
What does ‘VIN Programmed’ mean for me?
It means we flash the module with your vehicle’s specific Vehicle Identification Number (VIN) and the latest GM software before we ship it. This ensures it communicates perfectly with your van’s other computers (like the ECM and BCM) right out of the box. You get optimal performance without needing a dealership’s expensive programming service.
Is there a core charge for my old part?
What does ‘VIN Programmed’ mean for me?
It means we flash the module with your vehicle’s specific Vehicle Identification Number (VIN) and the latest GM software before we ship it. This ensures it communicates perfectly with your van’s other computers (like the ECM and BCM) right out of the box. You get optimal performance without needing a dealership’s expensive programming service.