Is your Buick Allure, Chevy Silverado, or GMC Yukon suffering from erratic shifting, getting stuck in gear, or displaying a transmission warning light? These are classic signs of a failing Transmission Control Module (TCM), the electronic brain of your automatic transmission. Restore your vehicle’s performance and drivability with this OEM-quality GM T42 Transmission Control Module, service part number 24241806. This isn’t just a replacement part; it’s a complete, plug-and-play solution, pre-programmed to your vehicle’s specific VIN for a hassle-free installation.
The Critical Role of Your Transmission Control Module
The TCM is a sophisticated computer that constantly communicates with your engine control module (ECM) and various sensors throughout your vehicle. It processes data like vehicle speed, engine load, and throttle position to execute precise, smooth gear shifts. It also controls the torque converter clutch lockup for improved fuel efficiency and manages fluid pressure to protect internal components. When the TCM begins to fail, this complex orchestration falls apart, leading to the frustrating and potentially damaging symptoms you’re experiencing.
Diagnosing a Faulty GM T42 Transmission Module
A failing GM T42 Transmission Module can manifest in several ways, often starting as intermittent issues before becoming a constant problem. A proper diagnosis often involves using a professional scan tool to read for specific Diagnostic Trouble Codes (DTCs). Codes like P0700 (Transmission Control System Malfunction) are a general indicator, while more specific codes related to solenoids (e.g., P0751, P0756) or pressure switches can point directly to an internal TCM failure. If you’re facing these codes alongside poor shifting performance, replacing the TCM is the most effective and reliable repair.
From the Diagnostic Bay
We recently had a 2008 Chevrolet Tahoe come into the shop with the complaint of harsh, banging shifts from 1st to 2nd gear and a persistent check engine light. The owner had already replaced a shift solenoid with no improvement. Our scan tool pulled a P0700 and a P0752 (Shift Solenoid A Stuck On). Knowing the history of the T42 module, we suspected an internal driver failure. Instead of chasing more parts, we installed one of our VIN-programmed T42 TCMs. After a 20-minute installation and clearing the codes, the Tahoe shifted like it just rolled off the factory floor. The pre-programmed module saved the customer time, money, and the headache of a dealership visit.
Symptoms of a Failing T42 TCM
- ✔️ Harsh, delayed, or unpredictable gear shifts.
- ✔️ Vehicle feels stuck in one gear, often referred to as “limp mode.”
- ✔️ Check Engine Light or Transmission Warning Light is illuminated on the dashboard.
- ✔️ Inability to upshift or downshift properly, leading to poor acceleration.
- ✔️ A noticeable decrease in fuel economy due to inefficient operation.
- ✔️ The torque converter fails to lock or unlock correctly, causing RPM fluctuations at highway speeds.
- ✔️ Complete loss of communication with the module, resulting in a no-start or no-shift condition.
The Definitive Solution: Pre-Programmed and Ready to Install
This isn’t a generic, one-size-fits-all part. Our key advantage is the comprehensive VIN programming service included with every purchase. We flash the module with the latest GM software specific to your vehicle’s VIN, ensuring it works seamlessly with your engine, ABS, and other systems right out of the box. This eliminates the need for expensive dealership programming or specialized tools, making it a true DIY-friendly repair. Built to strict OEM standards and backed by a one-year warranty, this module is engineered for lasting reliability.
This module is a direct replacement for a wide range of part numbers, including: 24252114, 24234503, 24230461, 24234274, 24241806, 24256960, and many more. It’s the ideal solution for countless GM vehicles equipped with 4-speed automatic transmissions like the 4L60E, 4L65E, and 4L70E.
Frequently Asked Questions
Why is VIN programming so important for a TCM?
VIN programming loads the module with the correct software, shift tables, and communication protocols for your specific vehicle configuration (engine size, axle ratio, tire size, etc.). Without it, a new TCM will not communicate correctly with other vehicle systems, leading to persistent shifting problems or even a no-start condition.
Will this part fix my P0700 trouble code?
A P0700 code is a general fault code indicating the TCM has detected a problem. While this module often resolves the root cause of a P0700, it’s crucial to diagnose any other accompanying codes. If the other codes point to solenoid or internal module faults, this part is the correct solution.
Is this an easy part to install myself?
For most DIYers with basic tools, yes. The TCM is typically located in the engine bay and is held in place by a few bolts with electrical connectors. The most common locations are near the battery, on the LH strut tower, or under the air cleaner box. The entire process usually takes less than 30 minutes.
Do I need to perform a transmission relearn procedure after installation?
Because our modules are programmed with the latest software updates, a specific relearn procedure is often not required. The module’s adaptive learning strategy will adjust to your driving style over the first 50-100 miles. Simply disconnect the battery during installation to clear any learned memory, and you’ll be good to go.
Is there a core charge or do I have to send my old part back?
No. We do not require a core return for this part. You can keep or dispose of your old module without any additional hassle or charges, simplifying the repair process for you.