Is Your GMC Yukon Experiencing Transmission Problems?
The transmission control module (TCM) is the electronic brain of your 2007-2009 GMC Yukon’s automatic transmission. It processes data from various sensors to ensure your vehicle shifts gears smoothly, efficiently, and at the correct time. When this critical component begins to fail, it can lead to a cascade of frustrating and potentially damaging drivability issues, making your reliable SUV feel unpredictable and unsafe. Ignoring the signs can lead to more significant transmission wear and costly repairs down the road.
From the Diagnostic Bay
We had a 2008 Yukon come into the shop with a classic complaint: “It shifts hard sometimes, and yesterday it wouldn’t shift out of 2nd gear.” The customer was worried they needed a full transmission rebuild. After hooking up the scanner, we saw a P0700 code and several solenoid performance codes. Instead of jumping to a mechanical failure, we checked the TCM connections and data. The data stream was erratic. We installed a VIN-programmed T42 module, cleared the codes, and took it for a test drive. The shifting was immediately crisp and smooth, just like it left the factory. A 30-minute part swap saved the customer thousands on an unnecessary transmission teardown.
Symptoms of a Failing 2007-2009 Yukon Transmission Module
- ✔ Erratic and Harsh Shifting: Your Yukon may slam into gear, hesitate between shifts, or feel like it’s slipping.
- ✔ Stuck in Gear / Limp Mode: The transmission may refuse to shift, often getting stuck in 2nd or 3rd gear to protect itself from further damage.
- ✔ Warning Lights: The Check Engine Light or a specific transmission warning light will illuminate on your dashboard.
- ✔ Diagnostic Trouble Codes (DTCs): A scan tool will often reveal codes like P0700 (Transmission Control System Malfunction) or other specific solenoid circuit codes (e.g., P0750, P0753, P0758).
- ✔ Poor Fuel Economy: Inefficient shifting and torque converter lock-up issues caused by a faulty TCM can lead to a noticeable decrease in MPG.
- ✔ No Communication: In severe cases, a scan tool may be unable to communicate with the TCM, indicating a complete module failure.
The Definitive Solution: A VIN-Programmed T42 TCM
This OEM-quality T42 Transmission Control Module, service part number 24243921, is the perfect solution for your vehicle. The most significant benefit is that it arrives at your door pre-programmed specifically for your Yukon’s Vehicle Identification Number (VIN). This critical step ensures that the module has the latest GM software updates and is perfectly calibrated to your vehicle’s specific configuration, including engine size, axle ratio, and tire size. This eliminates the need for expensive trips to the dealership for programming, making the installation a true plug-and-play process.
By replacing your old, failing unit with this precisely programmed 2007-2009 Yukon Transmission Module, you restore the intelligent control required for proper transmission function. It directly manages shift solenoids, torque converter clutch lockup, and line pressure, ensuring every gear change is seamless. This not only improves the driving experience but also protects the mechanical components of your transmission from the stress caused by erratic electronic signals.
Easy Installation for DIY and Professionals
Installation is straightforward. On most 2007-2009 GMC Yukon and similar GM trucks/SUVs, the TCM is located in the engine compartment, often next to the battery or under the air cleaner box. The process typically takes less than 30 minutes.
- Safety First: Always disconnect the negative battery terminal before starting any work on your vehicle’s electronics.
- Locate the Old TCM: Identify the module in your engine bay.
- Disconnect and Remove: Carefully unplug the electrical connectors and unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed TCM in place and securely reconnect the wiring harnesses.
- Reconnect Battery: Reattach the negative battery terminal.
- Final Steps: While the module is plug-and-play, it’s always a good practice to use a scan tool to clear any stored DTCs from the vehicle’s memory after installation.
With no core charge, you don’t have to worry about the hassle of returning your old part. This high-quality replacement 2007-2009 Yukon Transmission Module is built to meet or exceed original equipment standards and is backed by a one-year warranty for your peace of mind.
Frequently Asked Questions
What does the TCM do on a 2007-2009 GMC Yukon?
The Transmission Control Module (TCM) acts as the computer for your automatic transmission. It takes information from engine and vehicle speed sensors to control shift points, line pressure, and torque converter lockup, ensuring smooth and efficient operation.
Is this module ready to install right out of the box?
Yes. This module is expertly programmed to your vehicle’s specific VIN before shipping. This means it is ready for a plug-and-play installation without requiring any additional programming from a dealership.
Where is the TCM located on my 2008 Yukon?
On the 2007-2009 GMC Yukon, Chevrolet Tahoe, and similar models, the TCM is typically found in the engine compartment, mounted next to the battery on the driver’s side.
Will this part fix a P0700 trouble code?
A P0700 code is a general fault code indicating that the TCM has detected a problem and has requested the Check Engine Light to be turned on. While this module often resolves the root cause (like internal solenoid circuit faults), you should have the vehicle scanned for the more specific codes that accompany the P0700 to confirm the diagnosis.
Do I need to send my old TCM back?
No, there is no core charge for this part. You can keep or dispose of your old module without any additional fees or hassle.
My original part number is different. Will this still work?
Yes, this T42 module is a direct replacement for a wide range of GM service numbers, including 24252114, 24234503, 24243901, and many others listed in the product details. It is compatible with numerous GM vehicles from 2006-2014 equipped with 4-speed automatic transmissions.