Is your 2007 or 2008 GMC Yukon XL 1500 suffering from unpredictable shifting, getting stuck in gear, or throwing transmission codes? You’re not alone. As a technician with over two decades of experience, I’ve seen countless GM trucks and SUVs sidelined by a faulty Transmission Control Module (TCM). The TCM is the brain of your automatic transmission, and when it fails, it can cause a cascade of frustrating and potentially unsafe driving issues. This T42 Transmission Control Module, corresponding to part number 24235754, 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 completely. We will program this module to your vehicle’s specific VIN before shipping it to you. This means it arrives ready for a true plug-and-play installation, equipped with the latest GM software updates. This ensures perfect communication with your vehicle’s other computers, like the ECM, and restores the crisp, smooth shifting you expect from your Yukon XL.
Case Study: A Tricky Diagnosis
A customer brought in a 2008 Yukon XL 1500 with a complaint of intermittent ‘limp mode’—it would get stuck in 3rd gear without warning, and the check engine light was on. They had already replaced two shift solenoids at another shop with no success. My scan tool pulled a generic P0700 (Transmission Control System Malfunction) code. Instead of just chasing solenoids, I checked the data stream from the TCM. I noticed erratic voltage readings and communication dropouts, a classic sign of internal TCM failure. We installed one of our pre-programmed T42 modules. The entire job, from diagnosis to test drive, took less than an hour. The shifting was immediately corrected, the codes were gone, and the customer was back on the road, saving hundreds compared to a dealership visit.
Is Your Yukon Exhibiting These Transmission Problems?
A failing TCM can manifest in several ways. If you’re experiencing any of the following, this module is the likely solution for your 2007-2008 Yukon XL 1500 TCM issues:
- âś” Harsh, banging shifts or delayed gear engagement.
- âś” Vehicle is stuck in a single gear (often called ‘limp mode’).
- âś” Check Engine Light or Transmission Warning Light is illuminated.
- âś” Diagnostic Trouble Codes (DTCs) are present, such as P0700, P0750, P0755, or other solenoid-related faults.
- âś” A sudden drop in fuel economy or transmission overheating.
- âś” Complete loss of communication with the transmission module (no gear indicator on the dash).
A Straightforward Guide to Installation
Replacing the TCM on your Yukon XL is a job most DIYers can handle in their driveway in under 30 minutes. For the 2007-2008 Yukon XL 1500, the module is conveniently located in the engine compartment, right next to the battery.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the Module: Find the TCM mounted next to the battery in the engine bay. It will have several large electrical connectors attached.
- Disconnect and Remove: Carefully unplug the electrical harnesses. Then, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed TCM into place and securely reconnect the electrical harnesses.
- Final Steps: Reconnect the negative battery terminal. While the module is plug-and-play, it’s always best practice to use a basic OBD2 scan tool to clear any stored fault codes from the vehicle’s memory.
Verified Fitment For These GM Models
While this is the perfect 2007-2008 Yukon XL 1500 TCM, this versatile T42 module also fits a wide range of other General Motors vehicles equipped with 4-speed automatic transmissions like the 4L60E, 4L65E, and 4L70E. This part is interchangeable with numbers 24242391, 24234503, 24252114, and others.
- âś” GMC: YUKON (07-09), YUKON XL 1500 (07-08), SIERRA 1500/2500 (07-13), SAVANA 1500/2500/3500 (06-14), ENVOY (06-09), CANYON (08-12)
- âś” Chevrolet: TAHOE (07-09), SUBURBAN 1500 (07-08), AVALANCHE 1500 (07-08), SILVERADO 1500/2500 (07-13), EXPRESS 1500/2500/3500 (06-14), IMPALA (06-11), COBALT (06-10), HHR (06-11), MALIBU (06-10), TRAILBLAZER (06-09), COLORADO (08-12)
- âś” Cadillac: DTS (06-11)
- âś” Buick: LUCERNE (06-11), LACROSSE (06-09), ALLURE (06-09), RENDEZVOUS (06-07), RAINIER (06-07)
- âś” Pontiac: G6 (06-10), GRAND PRIX (06-08)
- âś” Saturn: VUE (07-10), AURA (07-09), ION (06-07)
- âś” Hummer: H3 (08-10)
- âś” Saab: 9-7X (06-09)
Frequently Asked Questions
Do I need to take this part to a dealer for programming?
No. This is the primary benefit of our service. We program the module to your vehicle’s VIN before it ships, so it arrives ready for installation without any need for a dealer visit or expensive scan tools.
Where is the TCM located on my 2008 Yukon XL 1500?
On the 2007-2008 GMC Yukon XL 1500, the Transmission Control Module (TCM) is located in the engine compartment, typically mounted right next to the battery.
Will this fix a P0700 trouble code?
A P0700 code is a general fault code indicating the TCM has detected a problem. In many cases, a failing TCM is the root cause. Replacing the module with our pre-programmed unit is a very common and effective fix for this and related transmission codes.
Is there a core charge for this part?
No, we do not require a core charge. You can keep your old part, which simplifies the process and saves you the hassle and expense of return shipping.
What kind of warranty is included?
This module is backed by our one-year warranty, giving you confidence and peace of mind in your repair.