Is your 2007-2008 GMC Yukon XL 1500 shifting erratically, getting stuck in gear, or throwing transmission codes? As a technician with over two decades of experience, I’ve seen these symptoms countless times, and they almost always point to a failing Transmission Control Module (TCM). The constant heat cycles in the engine bay take their toll on these sensitive electronics. This isn’t just an annoyance; it’s a reliability issue that can leave you stranded. Don’t let a faulty TCM dictate your driving experience or drain your wallet with dealership diagnostic fees.
This is a direct-replacement, OEM-quality T42 TCM, part number 24255280, that arrives at your door fully programmed to your vehicle’s specific VIN. That means no expensive trips to the dealer for programming. It’s a true plug-and-play solution designed to restore the crisp, predictable shifting your Yukon XL had from the factory. It correctly manages shift points, torque converter lockup, and line pressure, resolving the root cause of many transmission performance problems.
From the Diagnostic Bay
A customer brought in their ’07 Yukon XL complaining of harsh 1-2 shifts and occasionally getting stuck in 3rd gear (limp mode), with a P0700 code on the scanner. They were worried about a full transmission rebuild. After confirming power and ground to the TCM, we knew the internal logic had failed—a classic T42 issue. Instead of a $3000+ transmission job, we installed one of our VIN-programmed modules. The entire job took less than 30 minutes. After a quick battery disconnect to clear memory and a test drive, the shifts were buttery smooth. The customer saved thousands and drove away with confidence.
Is Your Yukon Exhibiting These Telltale Signs?
A failing TCM will give you clear warnings. If you’re experiencing any of the following, it’s time for a replacement:
- ✔ Harsh, banging, or delayed gear shifts.
- ✔ Vehicle is stuck in ‘limp mode’ and won’t shift out of 2nd or 3rd gear.
- ✔ Check Engine Light is on with transmission-specific Diagnostic Trouble Codes (DTCs) like P0700, P0750, P0753, P0758, or other solenoid codes.
- ✔ Complete loss of gear engagement or failure to upshift/downshift.
- ✔ A noticeable drop in fuel economy due to inefficient shifting.
- ✔ Intermittent communication loss with the transmission module.
Your 30-Minute Path to Smoother Shifts
Installing your new 2007-2008 Yukon XL 1500 TCM is a straightforward job for any DIYer. For the Yukon, it’s typically located right next to the battery.
- Safety First: Disconnect the negative terminal on your vehicle’s battery to prevent any electrical shorts and to help reset the system.
- Locate the Old Module: Find the TCM in the engine bay. It’s a small metal box with two large electrical connectors.
- Disconnect and Remove: Carefully unplug the two wiring harness connectors. Then, unbolt the module from its mounting bracket.
- Install the New TCM: Bolt the new, pre-programmed module into place and securely plug in the two wiring harness connectors. You’ll hear a click as they lock.
- Reconnect and Verify: Reconnect the negative battery terminal. Start the vehicle and check for any warning lights. Take a test drive to confirm the smooth shifting performance has been restored.
Verified Fitment Across the GM Family
While this is the perfect solution for your Yukon XL, this T42 TCM is also compatible with a wide range of GM vehicles equipped with 4-speed automatic transmissions like the 4L60E, 4L65E, and 4L70E. Please verify your part number or use our vehicle selector for guaranteed fitment. This module interchanges with part numbers: 24252114, 24234503, 24230461, 24234274, 24235340, 24235754, 24238856, 24239224, 24239926, 24240400, 24241806, 24243901, 24243921, 24256960, and more.
Choosing our VIN-programmed 2007-2008 Yukon XL 1500 TCM is the most reliable and cost-effective way to solve your transmission issues permanently. With a one-year warranty and no core charge, you can buy with complete confidence. Get your vehicle back on the road and shifting perfectly.
Frequently Asked Questions
Do I need to do any programming or flashing myself?
Absolutely not. We handle all the programming here using your vehicle’s VIN before we ship it. It is ready for installation right out of the box, saving you a trip to the dealership.
Where is the TCM located on my 2008 Yukon XL 1500?
On the 2007-2008 Yukon XL 1500, the Transmission Control Module is conveniently located in the engine compartment, mounted on a bracket right next to the battery. This makes for a very easy and accessible replacement.
Is a core charge required for this part?
No, there is no core charge. You can keep your old part or dispose of it without the hassle of returning a core.
Will this fix a P0700 trouble code?
A P0700 code is a general fault request from the TCM to the Engine Control Module (ECM) to turn on the check engine light. While this module often resolves the underlying issue causing the P0700 (like a failed solenoid driver), it’s important to scan for more specific P-codes (e.g., P0753) to confirm the TCM is the root cause.
What tools are needed for the installation?
You’ll only need basic hand tools. Typically, a 10mm socket or wrench to disconnect the battery and remove the module’s mounting bolts is all that’s required.