Restore Peak Performance to Your GMC’s Transmission
Is your 2007-2008 GMC Yukon XL 1500 suffering from harsh shifting, getting stuck in gear, or throwing transmission codes? These are classic signs of a failing Transmission Control Module (TCM). As a technician with over two decades of experience, I’ve seen firsthand how a faulty TCM can sideline an otherwise perfectly good truck. This isn’t just an annoyance; it’s a critical failure that affects your vehicle’s drivability, fuel economy, and safety. This T42 series TCM, part number 24235340, is the definitive solution to get your Yukon back to shifting smoothly and reliably.
The biggest hurdle with TCM replacement has always been the expensive and time-consuming trip to the dealership for programming. We eliminate that step entirely. By providing your vehicle’s VIN at checkout, we program the module with the latest GM software updates specifically for your truck. This means it arrives at your door ready for a true plug-and-play installation. This is the exact process we use in our shop to save customers time and money, and now you can do the same in your own garage. A new 2007-2008 Yukon XL 1500 TCM is the key to resolving those persistent electronic transmission faults for good.
From the Diagnostic Bay
I remember a 2008 Yukon that came into the shop with a complaint of intermittent, bone-jarring shifts and a P0700 code that wouldn’t stay cleared. The owner had already spent a small fortune at another shop replacing solenoids, thinking it was a mechanical issue inside the 4L60E transmission. After a quick data stream analysis, I noticed the command signals from the TCM were erratic. We installed one of our pre-programmed T42 modules, and the problem vanished instantly. It’s a powerful reminder that with modern vehicles, the brain is often the source of the problem, not the brawn.
Is Your Yukon Showing These Transmission Symptoms?
- ✔ Check Engine Light or Transmission Warning Light is illuminated on your dash.
- ✔ Your scanner is showing Diagnostic Trouble Codes (DTCs) like P0700, P0750, or other solenoid-related faults.
- ✔ The transmission shifts harshly, slams into gear, or experiences delayed engagement from Park to Drive.
- ✔ Your vehicle is stuck in a single gear, often called “limp mode,” and will not upshift or downshift.
- ✔ You’re experiencing a sudden drop in fuel efficiency or the transmission seems to be overheating.
- ✔ The truck hesitates or slips between gears, making acceleration feel unpredictable.
A Straightforward Guide to Installation
For the 2007-2008 Yukon XL 1500 TCM, the replacement is surprisingly simple and can be done in under 30 minutes with basic hand tools. This makes it an ideal project for a DIY enthusiast looking to save on labor costs.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the Module: On your Yukon XL 1500, the TCM is typically found in the engine compartment, mounted next to the battery.
- Disconnect and Remove: Carefully unplug the electrical connectors. Press the release tabs firmly. Then, unbolt the module from its mounting bracket.
- Install the New TCM: Bolt the new, pre-programmed module 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. While our programming resolves most issues, it’s good practice to use a basic scan tool to clear any old stored codes from the vehicle’s memory.
Verified Vehicle Compatibility List
This T42 Transmission Control Module is a direct-fit replacement for a wide range of General Motors vehicles equipped with 4-speed automatic transmissions (like the 4L60E, 4L65E, and 4L70E). While this page focuses on the 2007-2008 Yukon XL 1500 TCM, it also fits the following models. Please verify your specific model and location noted below.
- GMC Yukon / Yukon XL 1500 (2007-2008): Transmission; (next to battery)
- Chevrolet Tahoe / Suburban 1500 (2007-2008): Transmission; (next to battery)
- Chevrolet Silverado / GMC Sierra 1500 (2007-2013): Transmission; (next to battery), check for new body style in ’07.
- Cadillac DTS (2006-2011): Transmission; (RH front engine compartment)
- Chevrolet Impala (2006-2011): Transmission; (lower air cleaner housing)
- Hummer H3 (2008-2010): Transmission; (RH rear engine compartment)
- Chevrolet Colorado / GMC Canyon (2008-2012): Transmission; (RH rear engine compartment)
- …and many other GM cars, trucks, and SUVs from 2006-2014. Please see the full fitment list in the provided data for complete compatibility.
Frequently Asked Questions
What does “VIN Programmed” mean?
It means we load your vehicle’s specific Vehicle Identification Number (VIN) and the latest GM software onto the module before we ship it. This ensures it communicates perfectly with your vehicle’s other computers right out of the box, eliminating the need for expensive dealership programming.
Is this a difficult part to install myself?
Not at all. For most vehicles like the Yukon, it’s located in an easy-to-access spot in the engine bay and requires only basic hand tools. The entire process typically takes less than 30 minutes, making it a great DIY-friendly repair.
Do I need to send my old TCM back (core charge)?
No, there is no core charge for this part. You can keep your old module or dispose of it responsibly without any extra hassle or fees.
Will this fix a P0700 trouble code?
A P0700 code is a general transmission fault request, meaning the TCM has detected a problem and asked the main computer to turn on the check engine light. While this module often resolves the underlying cause of a P0700, it’s important to ensure there are no other mechanical issues. In many cases, a faulty TCM is the root cause.
What if I install it and still have problems?
Our modules are quality-tested and backed by a one-year warranty. If you continue to experience issues after installation, it could indicate a problem elsewhere in the system, such as a wiring harness or a mechanical component within the transmission. Our expert support team is here to help you diagnose the situation.