Is your 2008-2010 HUMMER H3 struggling with erratic shifting, getting stuck in gear, or throwing transmission codes? As a technician with over two decades of experience, I’ve seen firsthand how a failing Transmission Control Module (TCM) can sideline even the most rugged vehicles. The TCM is the electronic brain of your automatic transmission, and when it malfunctions, it can cause a host of frustrating and potentially damaging drivability issues. This T42 Transmission Control Module, part number 24230461, is the definitive solution, arriving pre-programmed to your H3’s specific VIN for a true plug-and-play repair.
Case Study: A Tricky Diagnosis
I remember a 2009 Hummer H3 that came into my shop with a complaint of intermittent, bone-jarring shifts and occasionally getting stuck in 3rd gear (limp mode). The owner had already replaced a shift solenoid with no luck. The scan tool showed a generic P0700 code. After checking the wiring harness for damage from off-road adventures, we focused on the TCM. The problem was heat-related; the module would only act up after 20 minutes of driving. Swapping in a VIN-programmed TCM like this one solved the problem instantly. It’s a classic failure mode for these modules, and this direct-fit part is the most reliable fix.
Is Your Hummer H3 Showing These Transmission Red Flags?
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. Ignoring these signs can lead to more significant transmission damage down the road.
- ✔ Harsh, delayed, or unpredictable gear shifts.
- ✔ Vehicle refuses to shift out of a certain gear (often called ‘limp mode’).
- ✔ Check Engine Light or Transmission Warning Light is illuminated.
- ✔ Diagnostic Trouble Codes (DTCs) are present, such as P0700, P0750, or other solenoid-related faults.
- ✔ A noticeable drop in fuel economy.
- ✔ Complete loss of communication with the transmission module.
Your 30-Minute Path to a Smooth-Shifting H3
One of the best features of this module is how simple the installation is, saving you hundreds in labor costs. You don’t need specialized tools, just basic hand tools. For the 2008-2010 Hummer H3, the TCM is conveniently located in the engine bay.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electronic component replacement.
- Locate the Module: On your Hummer H3, you’ll find the TCM in the right-hand rear of the engine compartment.
- Disconnect and Remove: Carefully unplug the electrical connectors. Be gentle with the locking tabs, as they can become brittle over time. Then, unbolt the old module from its mounting bracket.
- Install the New TCM: Mount the new module in place and securely fasten it. Reconnect the electrical connectors, ensuring they click into place.
- Final Steps: Reconnect the battery terminal. While our VIN programming handles the critical setup, it’s good practice to use a basic OBD-II scan tool to clear any stored fault codes from the vehicle’s memory. Start the engine and enjoy restored performance!
Why Choose a VIN-Programmed Module?
This isn’t just a generic part off the shelf. We program each 2008-2010 HUMMER H3 TCM with the latest GM software updates using your vehicle’s unique VIN. This critical step ensures that the module communicates perfectly with your H3’s engine computer and other systems, delivering optimal shift points, torque converter lockup strategy, and fuel efficiency right out of the box. You get a reliable, OEM-quality component without the added expense and hassle of a trip to the dealership for programming.
Verified Fitment for Your General Motors Vehicle
While this page focuses on the 2008-2010 HUMMER H3 TCM, this versatile T42 module is also a direct replacement for a wide array of GM vehicles. This part is interchangeable with service numbers 24252114, 24234503, 24234274, and others. Please verify your vehicle in the list below:
- HUMMER H3 (2008-2010) – Transmission; (RH rear engine compartment)
- CHEVROLET COLORADO (2008-2012) – Transmission; (RH rear engine compartment)
- GMC CANYON (2008-2012) – Transmission; (RH rear engine compartment)
- CHEVROLET SILVERADO & GMC SIERRA (2007-2013) – Transmission; (next to battery)
- CHEVROLET TAHOE & GMC YUKON (2007-2009) – Transmission; (next to battery)
- …and many more GM cars, trucks, and SUVs from 2006-2014.
Do I need to have the dealer program this TCM?
Do I need to have the dealer program this TCM?
No. This Transmission Control Module comes fully programmed to your vehicle’s VIN before shipping. It is ready for immediate installation without any need for additional programming or dealership visits.
Is this a difficult part for a DIYer to install?
Not at all. For the Hummer H3, the TCM is easily accessible in the engine bay. With basic hand tools, most people can complete the replacement in under 30 minutes. Just disconnect the battery, swap the module, and you’re done.
What is a core charge? Do I need to send my old part back?
There is no core charge for this part. A core charge is a deposit you pay until you return your old part. We don’t require this, so you can keep your old module without any hassle or extra cost.
What kind of warranty is included?
This part is backed by our one-year, hassle-free warranty. We stand by the quality and reliability of our programmed electronic modules, giving you peace of mind with your purchase.