End Your GMC Yukon’s Shifting Nightmares
If your 2007-2009 GMC Yukon is suffering from harsh shifts, delayed gear engagement, or is stuck in limp mode, you’re not just dealing with an annoyance—you’re facing a critical failure. The Transmission Control Module (TCM), specifically the T42 model in these trucks, is the brain behind your automatic transmission. When it fails, it can cause a cascade of problems, from poor fuel economy to a complete inability to shift. This replacement module, part number 24240400, is the definitive, reliable solution to restore your vehicle’s performance and get you back on the road with confidence.
A Technician’s Notebook: The Intermittent Ghost
I once had a 2008 Yukon in my bay with the most frustrating symptoms. The owner said it would occasionally refuse to shift out of 2nd gear, but only after driving for 20+ minutes. Of course, it behaved perfectly for me on test drives. We checked the fluid, solenoids, and wiring harness—all good. The scanner showed intermittent communication loss codes with the TCM. These T42 modules are notorious for failing under heat. After swapping in a pre-programmed module like this one, the problem vanished instantly. It’s a textbook failure I’ve seen dozens of times, and this part is the go-to fix.
Is Your Yukon Showing These Symptoms?
A failing TCM doesn’t always mean a dead transmission. Often, replacing this single electronic component can solve what feel like major mechanical issues. Watch for these common warning signs:
- ✔ Abrupt, jerky, or slamming shifts between gears.
- ✔ The vehicle gets stuck in a single gear (often 2nd or 3rd), known as “limp mode.”
- ✔ Check Engine Light or Transmission Warning Light is illuminated with Diagnostic Trouble Codes (DTCs) like P0700, P0750, or other solenoid-related faults.
- ✔ Failure to upshift or downshift, leading to poor acceleration and terrible gas mileage.
- ✔ A significant delay when shifting from Park into Drive or Reverse.
Why Our Pre-Programmed 2007-2009 Yukon TCM is the Smart Choice
This isn’t just a replacement part; it’s a complete solution. The biggest hurdle in replacing a modern TCM is the need for expensive dealership programming. We eliminate that step entirely. By providing your vehicle’s VIN at checkout, we program the module with the latest GM software specific to your Yukon. It arrives at your door ready for a true plug-and-play installation, saving you time and hundreds of dollars in dealer fees.
A Straightforward Guide to Installation
For the confident DIYer or professional mechanic, this job is incredibly simple and can be done in under 30 minutes with basic hand tools.
- Safety First: Always disconnect the negative terminal on your vehicle’s battery to prevent electrical shorts and reset the system.
- Locate the Module: On the 2007-2009 GMC Yukon, the TCM is typically located in the engine bay, right next to the battery.
- Swap the Part: Carefully unplug the electrical connectors from the old TCM. Unbolt it from its mounting bracket and set it aside. Bolt the new module in its place and securely reconnect the wiring harnesses.
- Final Steps: Reconnect the battery terminal. While the system has been reset, it’s best practice to use a basic OBD2 scan tool to clear any lingering fault codes from the vehicle’s memory.
Verified Vehicle Compatibility
This T42 Transmission Control Module is a direct fit for the 2007-2009 GMC Yukon and is also compatible with a wide range of other General Motors vehicles. It is interchangeable with part numbers 24252114, 24234503, 24230461, 24240400, and more. Please see the detailed list below:
YUKON 07-09 Transmission; (next to battery)
ENVOY 08-09 Transmission; (LH engine compartment)
SAVANA 3500 VAN 06-14 Transmission; (RH engine compartment)
VUE 07-08 Transmission; 2.4L, (LH front engine compartment)
G5 07-10 Transmission; (LH strut tower)
SIERRA 1500 PICKUP 07 Transmission; (new style, smooth door skin), (next to battery)
TAHOE 07-09 Transmission; (next to battery)
YUKON XL 1500 07-08 Transmission; (next to battery)
… and many more GM models from 2006-2014.
Frequently Asked Questions
Do I need to take this part to a dealer for programming?
Absolutely not. We pre-program the module to your vehicle’s VIN before shipping. It arrives ready for installation, saving you time and money.
Will this fix my transmission that is stuck in limp mode?
In a vast majority of cases, a faulty TCM is the direct cause of the vehicle entering limp mode. Replacing it with this module is a very common and effective solution for that exact problem.
Where is the TCM located on my 2008 GMC Yukon?
For the 2007-2009 Yukon, Tahoe, and Silverado/Sierra platform, the TCM is almost always found in the engine compartment, mounted on a bracket right next to the battery.
Is there a core charge for my old part?
No, there is no core charge. You can keep your old part or dispose of it without the hassle of returning it.
What kind of warranty comes with this module?
This module is backed by our one-year warranty, giving you peace of mind and assurance in the quality and reliability of your repair.