Fix Your Yukon’s Shifting Problems for Good
Is your 2007-2009 GMC Yukon suffering from harsh, erratic shifting, getting stuck in gear, or throwing transmission-related check engine light codes? You’re not alone. These are classic signs of a failing Transmission Control Module (TCM). As the electronic brain of your automatic transmission (like the 4L60E or 4L70E), the TCM is responsible for every gear change. When it falters, drivability and safety are compromised. This T42 series TCM, part number 24240449, is the definitive, reliable solution to restore your vehicle’s performance and peace of mind.
The biggest hurdle in replacing a TCM has always been the expensive and time-consuming trip to the dealership for programming. We eliminate that step entirely. By providing us with your vehicle’s VIN during checkout, we program the module specifically for 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. This isn’t just a replacement part; it’s a complete, hassle-free repair solution.
A Technician’s Notebook: The Misleading Solenoid Code
A customer brought in a 2008 Yukon XL with a P0752 code, indicating a ‘Shift Solenoid A Stuck On’ issue. The previous shop had already replaced the solenoid inside the transmission pan—a messy, time-consuming job—but the problem persisted. After a few minutes with the scan tool monitoring live data, I saw the command to the solenoid was erratic, not the solenoid’s response itself. The root cause wasn’t the mechanical part in the pan; it was the T42 TCM failing to send a clear signal. We installed a VIN-programmed TCM in under 20 minutes, cleared the codes, and the truck shifted perfectly. It’s a textbook example of how a faulty module can send you chasing the wrong parts. Always check the controller first!
Is Your Yukon Exhibiting These Telltale Signs?
- ✔ Hard, slamming shifts or jerky gear engagement.
- ✔ The transmission feels like it’s slipping between gears.
- ✔ Vehicle is stuck in “limp mode” and won’t shift past 2nd or 3rd gear.
- ✔ Check Engine Light is on with transmission-specific Diagnostic Trouble Codes (DTCs) like P0700, P0750, or other solenoid-related faults.
- ✔ Delayed shifting when moving from Park to Drive or Reverse.
- ✔ A noticeable drop in fuel economy or signs of the transmission overheating.
A Straightforward 30-Minute Installation Guide
Replacing the 2007-2009 Yukon TCM is a job most DIYers can handle with basic tools. On these GMT900 trucks, the module is conveniently located in the engine bay.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery to prevent electrical shorts and help reset the system.
- Locate the TCM: On your Yukon, it’s typically mounted next to the battery under the hood. It’s a silver box with large electrical connectors.
- Disconnect and Remove: Carefully unclip the wiring harness connectors. Then, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed TCM into place and securely reconnect the wiring harnesses. You should hear a ‘click’ as they lock in.
- Final Steps: Reconnect the battery terminal. Start the vehicle and use a basic OBD2 scan tool to clear any stored fault codes from the computer’s memory. Test drive to confirm smooth shifting.
Verified Vehicle Compatibility
This module is a direct replacement for part number 24240449 and is interchangeable with service numbers such as 24252114, 24234503, and others. While this page focuses on the 2007-2009 GMC Yukon, it also fits a wide range of other GM vehicles. Please verify your specific model below:
- GMC Yukon / Yukon XL 1500 (2007-2009): Transmission; (next to battery)
- Chevrolet Tahoe / Suburban 1500 (2007-2009): Transmission; (next to battery)
- Chevrolet Silverado 1500 (2007-2013): Transmission; (new style, smooth door skin), (next to battery), w/o hybrid
- GMC Sierra 1500 (2007-2013): Transmission; (new style, smooth door skin), (next to battery), w/o hybrid
- Cadillac DTS (2006-2011): Transmission; (RH front engine compartment)
- Chevrolet Impala (2006-2011): Transmission; (lower air cleaner housing)
- GMC Envoy / Chevrolet Trailblazer (2006-2009): Transmission; (LH engine compartment)
- Hummer H3 (2008-2010): Transmission; (RH rear engine compartment)
- …and many other GM cars, trucks, and SUVs from 2006-2014. Please see the full fitment list for details.
Frequently Asked Questions
What does ‘VIN Programmed’ actually mean?
It means we load your vehicle’s unique Vehicle Identification Number (VIN) and the latest GM software onto the module before shipping. This ensures it communicates perfectly with your Yukon’s engine computer and other systems right out of the box, eliminating the need for a dealership visit.
Do I need any special tools to install this?
No special tools are required. A basic socket set to remove the module’s mounting bolts and disconnect the battery is all you’ll need. The entire process typically takes less than 30 minutes.
Will this fix a P0700 trouble code?
A P0700 code is a general fault request from the TCM to the main engine computer to turn on the check engine light. In many cases, a failing TCM is the root cause. Replacing it often resolves the P0700 and any other specific transmission codes (like P0752, P0757, etc.) that were present.
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 needing to ship it back to us, making the repair process simpler and faster.