If you’re dealing with a transmission that seems to have a mind of its own in your 2007-2008 GMC Yukon XL 1500, you’ve come to the right place. As a technician with over two decades of experience under the hood, I’ve seen countless GM trucks and SUVs roll into the shop with frustrating shifting problems. More often than not, the culprit is a failing Transmission Control Module (TCM). This isn’t just an inconvenience; it affects your vehicle’s performance, fuel economy, and safety. This T42 series TCM, part number 24234503, is the definitive solution to get your Yukon XL driving like new again.
The TCM is the brain of your automatic transmission, controlling everything from shift points to torque converter lockup. When it starts to fail, the symptoms can be unpredictable and concerning. This replacement module is meticulously prepared to OEM specifications and, most importantly, comes pre-programmed to your vehicle’s specific VIN. This means you can skip the expensive trip to the dealership for programming—it’s a true plug-and-play fix that you or your mechanic can perform quickly, restoring the crisp, reliable shifting you depend on.
Is Your Yukon Exhibiting These Telltale Signs?
A faulty TCM can manifest in several ways. If you’re experiencing any of the following, it’s a strong indicator that your module needs replacement:
- ✔ Harsh, slamming shifts or erratic gear changes that happen without warning.
- ✔ The vehicle feels stuck in one gear, often called “limp mode,” making it difficult to accelerate.
- ✔ Your Check Engine Light or a dedicated transmission warning light is illuminated on the dash.
- ✔ When you scan for codes, you see Diagnostic Trouble Codes (DTCs) like P0700 (Transmission Control System Malfunction) or various solenoid-specific codes (e.g., P0751, P0756).
- ✔ A noticeable drop in fuel efficiency as the transmission isn’t operating in the optimal gear.
- ✔ Complete failure to shift up or down, or a long delay when shifting from Park to Drive or Reverse.
Case Study: A Tricky Diagnosis
I remember a 2008 Yukon XL that came in with an intermittent problem. The owner said it would shift perfectly for days, then suddenly start slamming into gear at stoplights. There were no consistent codes, just a generic P0700 that would pop up and disappear. We checked the fluid, wiring, and solenoids—all seemed fine. After connecting a scope, we saw the TCM was sending erratic voltage signals, but only when it heated up after 20 minutes of driving. Replacing the TCM with a VIN-programmed unit like this one solved the problem instantly. It’s a classic failure mode for these T42 modules, where heat exposure eventually degrades internal components.
DIY Installation in Under 30 Minutes
One of the best features of this module is its straightforward installation. You don’t need a lift or specialized tools, making it a perfect job for a Saturday morning. For your 2007-2008 Yukon XL 1500, the TCM is conveniently located in the engine bay, right next to the battery.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts and to help reset the system’s memory.
- 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 unclip the wiring 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. Reconnect the wiring harnesses, ensuring they click securely into position.
- Final Steps: Reconnect the negative battery terminal. While the system may have reset, it’s best practice to use a basic OBD2 scan tool to clear any lingering fault codes from the vehicle’s memory. Start the engine and take it for a test drive to confirm smooth operation.
Verified Fitment for Your General Motors Vehicle
This T42 TCM is a direct replacement for a wide range of GM vehicles equipped with 4-speed automatic transmissions like the 4L60E, 4L65E, and 4L70E. It is interchangeable with part numbers 24252114, 24234503, 24230461, 24234274, and others. While this page focuses on the 2007-2008 Yukon XL 1500 TCM, it also fits the following models:
ALLURE 06-09 (lower air cleaner housing) | AVALANCHE 1500 07-08 (next to battery) | AURA 07-09 (LH frame rail front) | CANYON 08-12 (RH rear engine compartment) | COBALT 06-10 (LH strut tower) | COLORADO 08-12 (RH rear engine compartment) | DTS 06-11 (RH front engine compartment) | ENVOY 06-09 (LH engine compartment) | EXPRESS VANS 06-14 (RH engine compartment) | G5 07-10 (LH strut tower) | G6 06-10 (LH strut tower) | GRAND PRIX 06-08 (lower air cleaner housing) | HHR 06-11 (LH engine compartment) | HUMMER H3 08-10 (RH rear engine compartment) | IMPALA 06-11 (lower air cleaner housing) | LACROSSE 06-09 (lower air cleaner housing) | LUCERNE 06-11 (LH engine compartment) | MALIBU 06-10 (LH frame rail) | MONTE CARLO 06-07 (lower air cleaner housing) | SAAB 9-7X 06-09 (LH engine compartment) | SIERRA 1500/2500 07-13 (next to battery) | SILVERADO 1500/2500 07-13 (next to battery) | SUBURBAN 1500 07-08 (next to battery) | TAHOE 07-09 (next to battery) | TRAILBLAZER 06-09 (LH engine compartment) | VUE 07-10 (engine compartment) | YUKON 07-09 (next to battery) | and more.
Frequently Asked Questions
Do I need to take my vehicle to a dealer for programming?
No. This module comes fully pre-programmed to your vehicle’s VIN. You simply provide us with your VIN during checkout, and we handle all the software flashing. It arrives ready for plug-and-play installation.
Is this a difficult part to install myself?
Not at all. For most vehicles like the Yukon XL 1500, it’s located in an easily accessible spot in the engine bay. With basic hand tools, the swap takes less than 30 minutes, making it an ideal DIY repair.
What is the warranty on this TCM?
This module is backed by a one-year, hassle-free warranty, giving you confidence and peace of mind in your repair.
Will this fix a P0700 trouble code?
A P0700 code indicates a general fault in the transmission control system. While a failing TCM is a very common cause, this code can also be triggered by other issues. However, if you’re also experiencing symptoms like erratic shifting or limp mode, replacing the TCM is the most likely solution.
Is there a core charge for my old part?
No, there is no core charge. You are not required to send your old, faulty module back to us, saving you time and shipping costs.