Is your 2007-2009 GMC Yukon suffering from erratic shifting, 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). A faulty TCM can make your reliable SUV feel unpredictable and unsafe. This isn’t just an annoyance; it’s a critical failure that compromises your vehicle’s performance and your peace of mind.
This is the direct-fit, OEM-quality solution you need. This T42 TCM, part number 24256960, is expertly pre-programmed to your Yukon’s specific Vehicle Identification Number (VIN). This means you can skip the expensive trip to the dealership for programming. It arrives at your door ready for a true plug-and-play installation, restoring the crisp, smooth shifting and reliable performance you expect from your vehicle.
Is Your Yukon Exhibiting These Telltale Signs?
A failing TCM doesn’t always cause a complete breakdown right away. It often starts with subtle, intermittent issues. If you’re experiencing any of the following, it’s a strong indicator that your TCM is the culprit.
- ✔ Harsh, slamming shifts or jerky gear engagement.
- ✔ The vehicle feels stuck in one gear (often called “limp mode”).
- ✔ Your Check Engine Light is on, with Diagnostic Trouble Codes (DTCs) like P0700, P0750, or other solenoid-related faults.
- ✔ Delayed shifting, where the engine revs high before changing gears.
- ✔ A noticeable drop in fuel economy or signs of the transmission overheating.
- ✔ Complete loss of communication with the transmission, preventing it from shifting at all.
From the Diagnostic Bay: The Case of the Ghostly Glitch
A customer brought in his ’08 Yukon, complaining of a really frustrating problem. He said about once a week, the transmission would slam into gear when accelerating from a stop. By the time he got to my shop, it would be driving perfectly fine, and no codes were stored. We checked fluids, wiring, and solenoids—everything looked good. The issue was so intermittent, it was a real head-scratcher. Based on my experience with these GM platforms, I suspected the TCM was failing internally under certain thermal conditions. We swapped in a VIN-programmed TCM, and the customer called back a month later to say the problem was completely gone. This part solved a ghost in the machine that other checks couldn’t find.
A Straightforward Guide to Installation
Replacing the 2007-2009 Yukon Transmission Control Module is a job most DIYers can handle in their own driveway in under an hour. On these GMT900 trucks, the TCM is typically located in the engine bay, right next to the battery. You don’t need specialized tools, just basic hand tools.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts and help reset the system.
- Locate the Module: Find the TCM mounted next to the battery. It’s a silver box with several large electrical connectors.
- Disconnect and Remove: Carefully unplug the electrical harnesses. They have locking tabs, so be gentle. Then, unbolt the module from its mounting bracket.
- Install the New TCM: Bolt the new, pre-programmed module into place. Securely plug in the electrical connectors until they click, ensuring a solid connection.
- Final Steps: Reconnect the negative battery terminal. While our programming handles the critical setup, it’s always good practice to use a basic OBD-II scan tool to clear any lingering fault codes from the vehicle’s memory.
Guaranteed Vehicle Compatibility
This module is a direct replacement for part number 24256960 and other interchangeable service numbers. It is engineered for a precise fit in the following vehicles, among many others:
- ✔ GMC Yukon / Yukon XL 1500: 2007, 2008, 2009
- ✔ Chevrolet Tahoe / Suburban 1500: 2007, 2008, 2009
- ✔ Chevrolet Silverado 1500 / GMC Sierra 1500: 2007-2013 (New Body Style)
- ✔ Chevrolet Avalanche: 2007-2008
- ✔ Cadillac DTS: 2006-2011
- ✔ Buick Lucerne / LaCrosse: 2006-2011
- ✔ Hummer H3: 2008-2010
- ✔ …and many other GM cars, trucks, and SUVs from 2006-2014. Please verify fitment for your specific model.
Frequently Asked Questions
Do I need to take my Yukon to the dealer after installing this?
Absolutely not. The main benefit of this TCM is that we program it to your vehicle’s VIN before shipping. This makes it a true plug-and-play part, saving you hundreds in dealership programming fees.
Is this part difficult to install for a beginner?
Not at all. For most Yukons and Tahoes, the TCM is located right next to the battery and is held in by a few bolts. With basic hand tools, most people can complete the swap in 30-45 minutes.
What happens if I don’t replace a failing TCM?
Ignoring a failing TCM can lead to more severe problems. Continued harsh shifting can cause premature wear on internal transmission components like clutches and bands, potentially leading to a complete transmission failure that costs thousands to repair.
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 root cause (like a failed solenoid driver), you should always diagnose the specific codes the TCM has stored (e.g., P0752, P0757) to confirm the TCM itself is the issue.
Is there a core charge for my old part?
No, there is no core charge. You can keep your old module or dispose of it without the hassle of shipping it back to us.