Is your 2006-2014 Chevrolet Express 2500 van letting you down with rough shifting, getting stuck in gear, or a glowing check engine light? When your workhorse is off the road, you’re losing time and money. As a technician with over two decades of experience, I’ve seen countless work vans sidelined by a faulty Transmission Control Module (TCM). The constant heat and vibration in the engine bay take their toll, leading to internal circuit failures that wreak havoc on your transmission’s performance.
This T42 Transmission Control Module is the direct, reliable solution to get your van running right again. The most critical feature is that it arrives at your door fully VIN-programmed. This means you can skip the expensive trip to the dealership and the hassle of their programming fees. We flash the module with the latest GM software updates specific to your van’s VIN, making it a true plug-and-play repair. This is the definitive fix for those frustrating transmission codes and drivability issues.
Case Study: A Tricky Diagnosis
A few months back, a local contractor brought in his ’11 Express 2500. The van was stuck in what we call ‘limp mode’—it wouldn’t shift out of 3rd gear. His scanner was showing a generic P0700 code. While this code points to a transmission issue, it doesn’t specify the cause. After a quick check of the main harness connector for corrosion (always the first step), we diagnosed a failed T42 TCM. An internal short was preventing the solenoids from getting the correct signals. We installed one of our pre-programmed modules, cleared the codes, and had his van back on the road and earning him money in under an hour.
Is Your Van Exhibiting These T42 TCM Failure Signs?
A failing TCM can manifest in several ways. If you’re experiencing any of the following, this module is likely the solution you need. This is a common failure point I’ve diagnosed on hundreds of GM trucks and vans.
- ✔ Harsh, slamming, or erratic gear shifts.
- ✔ Delayed engagement when shifting from Park to Drive or Reverse.
- ✔ Vehicle is stuck in one gear (limp mode).
- ✔ Check Engine Light is on with transmission-related Diagnostic Trouble Codes (DTCs) like P0700, P0751, P0753, P0756, or other solenoid circuit faults.
- ✔ Poor fuel economy and a feeling of sluggish performance.
- ✔ Complete loss of communication with the transmission module.
A Straightforward Guide to Installing Your Express 2500 Transmission Module
This is a job most DIYers or any professional mechanic can complete quickly. No specialized tools are needed.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work. This prevents accidental shorts and helps reset the vehicle’s electronic systems.
- Locate the Module: On the 2006-2014 Express and Savana vans, the TCM is located in the engine compartment on the right-hand (passenger) side, mounted near the inner fender.
- Disconnect and Remove: Carefully unclip the electrical connectors from the old module. Press the release tabs firmly to avoid damaging them. Then, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed module into place and securely reconnect the electrical connectors. You should hear a ‘click’ as they lock in.
- Reconnect and Verify: Reconnect the negative battery terminal. Start the vehicle and allow it to idle for a few minutes. Use a standard OBD2 scan tool to clear any stored fault codes. Take the van for a test drive to confirm smooth shifting has been restored.
Verified Vehicle Compatibility List
This T42 TCM, part number 24239224, is a direct replacement for a wide range of General Motors vehicles. Please verify your model and the module location noted below.
- CHEVROLET EXPRESS 2500 VAN (2006-2014) – Transmission; (RH engine compartment)
- CHEVROLET AVALANCHE 1500 (2007-2008) – Transmission; (next to battery)
- CHEVROLET COBALT (2006-2010) – Transmission; (LH strut tower)
- CHEVROLET COLORADO (2008-2012) – Transmission; (RH rear engine compartment)
- CHEVROLET EXPRESS 1500/3500 VAN (2006-2014) – Transmission; (RH engine compartment)
- CHEVROLET HHR (2006-2011) – Transmission; (LH engine compartment)
- CHEVROLET IMPALA (2006-2011) – Transmission; (lower air cleaner housing)
- CHEVROLET MALIBU (2006-2010) – Transmission; (LH frame rail)
- CHEVROLET MONTE CARLO (2006-2007) – Transmission; (lower air cleaner housing)
- CHEVROLET SILVERADO 1500/2500 PICKUP (2007-2013) – See specific options in main description
- CHEVROLET SSR (2005-2006) – Transmission; (front LH frame)
- CHEVROLET SUBURBAN 1500 (2007-2008) – Transmission; (next to battery)
- CHEVROLET TAHOE (2007-2009) – See specific options in main description
- CHEVROLET TRAILBLAZER & EXT (2006-2009) – Transmission; (LH engine compartment)
- GMC CANYON (2008-2012) – Transmission; (RH rear engine compartment)
- GMC ENVOY & XL (2006-2009) – Transmission; (LH engine compartment)
- GMC SAVANA 1500/2500/3500 VAN (2006-2014) – Transmission; (RH engine compartment)
- GMC SIERRA 1500/2500 PICKUP (2007-2013) – See specific options in main description
- GMC YUKON & XL 1500 (2007-2009) – See specific options in main description
- BUICK ALLURE/LACROSSE (2006-2009) – Transmission; (lower air cleaner housing)
- BUICK LUCERNE (2006-2011) – Transmission; (LH engine compartment)
- BUICK RAINIER (2006-2007) – Transmission
- BUICK RENDEZVOUS (2006-2007) – Transmission; (air cleaner box)
- CADILLAC DTS (2006-2011) – Transmission; (RH front engine compartment)
- HUMMER H3 (2008-2010) – Transmission; (RH rear engine compartment)
- PONTIAC G5/G6 (2006-2010) – Transmission; (LH strut tower)
- PONTIAC GRAND PRIX (2006-2008) – Transmission; (lower air cleaner housing)
- SATURN AURA (2007-2009) – Transmission; (LH frame rail front)
- SATURN ION (2006-2007) – Transmission; (behind LH strut tower)
- SATURN VUE (2007-2010) – See specific options in main description
- SAAB 9-7X (2006-2009) – Transmission; (LH engine compartment)
This module also interchanges with part numbers: 24252114, 24234503, 24230461, 24234274, 24235340, 24235754, 24238856, 24239224, 24239926, 24240400, 24241806, 24243901, 24243921, 24255280, 24256960, and more.
Frequently Asked Questions
Do I need to have this module programmed by a dealership?
No. We pre-program the module to your vehicle’s VIN before shipping. It is ready for installation right out of the box, saving you time and money.
What exactly does a T42 TCM do?
The T42 is the specific type of Transmission Control Module GM used for its 4-speed automatic transmissions like the 4L60E and 4L80E. It acts as the transmission’s brain, controlling shift solenoids, line pressure, and torque converter lockup based on data from the engine and other sensors.
Where is the TCM on my 2008 Express 2500 van?
For the 2006-2014 Express and Savana van series, the TCM is consistently located in the engine compartment on the right-hand (passenger side).
Will this part fix a P0700 trouble code?
A P0700 code is a general fault request from the TCM to the main engine computer to turn on the check engine light. While this module often resolves the underlying issue causing the P0700, you should scan for more specific P-codes (like P07xx) to confirm the TCM is the root cause.
Is there a core charge for my old part?
No, there is no core charge. You can keep your old module, so you don’t have to worry about the cost or hassle of shipping it back.