Restore Flawless Shifting to Your GMC Yukon XL
If you’re dealing with the frustration of a GMC Yukon that’s shifting harshly, getting stuck in gear, or throwing transmission codes, you’ve come to the right place. As a technician with over two decades of experience, I’ve seen countless GM vehicles sidelined by a faulty Transmission Control Module (TCM). The T42 module is the brain of your automatic transmission, and when it fails, it can mimic a whole range of expensive mechanical problems. This VIN-programmed T42 TCM is the definitive, no-hassle solution to get your 2007-2008 Yukon XL 1500 TCM functioning like new again, without a costly trip to the dealership for programming.
This isn’t just a replacement part; it’s a direct solution engineered to OEM specifications. We handle the complex part for you: upon ordering, we program the module with your vehicle’s specific VIN. This ensures that it communicates perfectly with your engine computer (ECM) and other vehicle systems right out of the box. It arrives ready to install, saving you hundreds in diagnostic and programming fees that dealers charge. You’re getting a reliable fix that restores the precise, smooth performance you expect from your truck.
Case Study: The Yukon That Wouldn’t Shift
A customer brought in a 2008 Yukon XL 1500 that was stuck in what we call ‘limp mode’—it wouldn’t shift past 3rd gear, and the check engine light was on. The owner had already spent money replacing a couple of shift solenoids at another shop, but the problem persisted. A quick scan showed a P0700 (Transmission Control System Malfunction) code. Instead of just chasing solenoid codes, my experience pointed to the controller. We ordered one of our pre-programmed T42 modules. The installation took less than 20 minutes, and after a battery disconnect to clear the memory, the Yukon was shifting perfectly on the test drive. The customer saved time and avoided further incorrect repairs by addressing the root cause: the failing 2007-2008 Yukon XL 1500 TCM.
Is Your Yukon XL Exhibiting These Telltale TCM Failure Signs?
A failing TCM can cause a cascade of confusing symptoms. Before you suspect a full transmission rebuild, check if your vehicle is showing these common signs of a bad module. I’ve diagnosed hundreds of these, and the patterns are often very clear:
- ✔ Harsh, jerky, or erratic gear shifts.
- ✔ The vehicle feels stuck in one gear (often 2nd or 3rd) and won’t upshift or downshift.
- ✔ Check Engine Light or Transmission Warning Light is illuminated with codes like P0700, P0750, P0753, P0758, or other solenoid-related DTCs.
- ✔ Delayed engagement when shifting from Park to Drive or Reverse.
- ✔ A noticeable decrease in fuel economy.
- ✔ The torque converter fails to lock up at highway speeds, causing high RPMs.
Your 30-Minute Path to a Smooth-Shifting Yukon
One of the best parts about this solution is its simplicity. For most DIYers or any professional mechanic, this is a quick and straightforward job. The TCM on the Yukon is typically located right next to the battery in the engine bay.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work. This prevents short circuits and helps reset the vehicle’s adaptive memory.
- Locate the Module: On your 2007-2008 Yukon XL 1500, find the TCM mounted next to the battery. It’s a silver box with several large electrical connectors.
- Disconnect and Remove: Carefully unplug the electrical connectors. They have locking tabs that may need to be gently pried up. Then, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed TCM into place. Securely plug in the electrical connectors until they click, ensuring a solid connection.
- Reconnect and Verify: Reconnect the negative battery terminal. Start the vehicle and let it idle for a minute. Take it for a test drive to confirm that shifting has returned to normal. Use a scan tool to clear any lingering fault codes if necessary.
Verified Vehicle Compatibility List
This T42 Transmission Control Module is a direct fit for a wide range of General Motors vehicles equipped with 4-speed automatic transmissions like the 4L60E, 4L65E, and 4L70E. While this page is dedicated to the 2007-2008 Yukon XL 1500 TCM, it also fits the following models. Always verify your part number (24235732) or contact us with your VIN.
- GMC: Yukon, Yukon XL 1500, Sierra 1500/2500, Savana 1500/2500/3500, Envoy, Canyon
- Chevrolet: Tahoe, Suburban 1500, Silverado 1500/2500, Avalanche 1500, Express 1500/2500/3500, Impala, Monte Carlo, Cobalt, HHR, Colorado, SSR
- Cadillac: DTS
- Buick: LaCrosse, Lucerne, Allure, Rainier, Rendezvous
- Pontiac: G5, G6, Grand Prix, Pursuit
- Saturn: Vue, Aura, Ion
- Hummer: H3
- Saab: 9-7X
Interchangeable Part Numbers: 24252114, 24234503, 24230461, 24234274, 24235340, 24235754, 24238856, 24239224, 24239926, 24240400, 24241806, 24243901, 24243921, 24255280, 24256960, 24235732, 24235753, 24240449, YNXS.
Frequently Asked Questions
Do I need to take this part to a dealer for programming?
No. This is the biggest benefit. We program the module to your vehicle’s VIN before shipping it. This makes it a true plug-and-play installation, saving you time and the high cost of dealership programming.
Is this a difficult part for a DIYer to install?
Not at all. If you can use basic hand tools and disconnect a battery, you can replace this module. On the Yukon XL, it’s easily accessible in the engine bay, and the entire process usually takes less than 30 minutes.
What if I install it and my problem doesn’t go away?
While this module fixes the vast majority of electronic shifting issues, transmissions are complex. If the problem persists, it could indicate a mechanical issue within the transmission itself (like a worn clutch pack or faulty solenoid). Our pre-programmed TCM helps you confidently rule out the electronics as the cause.
Is there a core charge for my old part?
No, there is no core charge. You can keep your old part, so there’s no need to worry about the hassle and expense of shipping it back to us.
How do I provide my VIN for programming?
You will be prompted to enter your vehicle’s 17-digit VIN during the checkout process. Please double-check it for accuracy to ensure perfect programming.