Fix Your Transmission Problems with a Plug-and-Play Solution
If you’re dealing with a 2007 GMC Sierra 2500 that’s shifting erratically, stuck in limp mode, or throwing transmission codes, 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 sidelined by a faulty Transmission Control Module (TCM). The T42 module, in particular, is the brain of your automatic transmission, and when it fails, it can cause a cascade of frustrating and potentially damaging issues. This replacement T42 TCM, part number 24240449, is the reliable, straightforward fix you need.
The biggest headache with replacing a TCM is usually the required trip to the dealership for expensive programming. We eliminate that step entirely. We pre-program this module to your truck’s specific Vehicle Identification Number (VIN) before it ships. This means it arrives ready for a true plug-and-play installation, restoring communication and precise control over your 4L60E, 4L65E, 4L70E, or 4L80E transmission. Get your truck back to shifting smoothly and reliably without the dealer hassle.
From the Diagnostic Bay: The Case of the Confusing Codes
A customer brought in a 2008 Silverado with a classic complaint: intermittent harsh 1-2 shifts and a persistent Check Engine Light. He’d already replaced two shift solenoids based on a P0750-series code, but the problem kept returning. My scan tool showed good solenoid resistance, but live data revealed erratic command signals from the TCM. This is a textbook scenario I’ve diagnosed hundreds of times. The internal drivers on the original T42 module were failing under heat, causing intermittent signal loss. We installed one of our VIN-programmed modules, and the truck was shifting perfectly within an hour. The root cause wasn’t the solenoids; it was the computer controlling them. This highlights why a quality 2007 Sierra 2500 TCM is often the real solution.
Is Your Truck Showing These Telltale Signs of TCM Failure?
A failing TCM can manifest in several ways. If you’re experiencing any of the following, it’s highly likely this module is the culprit:
- ✔ Harsh, slamming, or delayed gear shifts.
- ✔ Vehicle is stuck in a single gear (often called “limp mode”).
- ✔ Check Engine Light or Transmission Warning Light is on.
- ✔ Diagnostic Trouble Codes (DTCs) like P0700 (Transmission Control System Malfunction), P0750-P0758 (Shift Solenoid errors), or other transmission-related faults are present.
- ✔ Complete loss of gear engagement or failure to upshift/downshift.
- ✔ Noticeably worse fuel economy.
A Straightforward Guide to Installation
One of the best features of this part is how simple the installation is. For most DIYers or any professional mechanic, this is a quick job. For a 2007 Sierra 2500 TCM, the module is typically located in the engine compartment right next to the battery.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the Module: On your Sierra, find the TCM mounted next to the battery. It will have several large electrical connectors.
- Disconnect and Remove: Carefully unplug the electrical connectors. Press the release tabs firmly. 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. You should hear a click as they lock in.
- Final Steps: Reconnect the battery terminal. While the module is pre-programmed, it’s always good practice to use a basic scan tool to clear any stored DTCs from the vehicle’s memory.
Verified Fitment For a Wide Range of GM Vehicles
While this is the correct part for your Sierra, this T42 module is also a direct replacement for many other GM vehicles. It is interchangeable with part numbers 24252114, 24234503, 24240449, and others. Please verify your specific model below:
GMC: SIERRA 1500/2500 (2007-2013), YUKON / YUKON XL (2007-2009), SAVANA 1500/2500/3500 (2006-2014), ENVOY (2006-2009), CANYON (2008-2012)
Chevrolet: SILVERADO 1500/2500 (2007-2013), TAHOE (2007-2009), SUBURBAN (2007-2008), EXPRESS 1500/2500/3500 (2006-2014), AVALANCHE (2007-2008), COLORADO (2008-2012), COBALT (2006-2010), HHR (2006-2011), IMPALA (2006-2011), MALIBU (2006-2010), MONTE CARLO (2006-2007), SSR (2005-2006), TRAILBLAZER (2006-2009)
Cadillac: DTS (2006-2011)
Buick: LACROSSE (2006-2009), LUCERNE (2006-2011), RAINIER (2006-2007), RENDEZVOUS (2006-2007)
Pontiac: G5 (2007-2010), G6 (2006-2010), GRAND PRIX (2006-2008), PURSUIT (2006)
Saturn: AURA (2007-2009), ION (2006-2007), VUE (2007-2010)
Hummer: H3 (2008-2010)
Saab: 9-7X (2006-2009)
Frequently Asked Questions
Is this part difficult to install myself?
Not at all. For a 2007 Sierra, it’s located next to the battery and requires only basic hand tools. Since it comes pre-programmed, it’s a simple unbolt-and-replace job that typically takes less than 30 minutes.
What does ‘VIN Programmed’ mean for me?
It means you can skip the expensive trip to a dealership for programming. We flash the module with your vehicle’s specific software using your VIN before we ship it. This ensures it works correctly with your engine and transmission right out of the box.
Will this fix a P0700 trouble code?
A P0700 code is a general fault request from the TCM to the main engine computer (ECM) to turn on the check engine light. While this module often resolves the underlying issue causing the P0700, you should scan for more specific P-codes (like P0751, P0756, etc.) to confirm the diagnosis. In many cases, a faulty TCM is the root cause.
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, which simplifies the process for you.
How is this different from a used part from a junkyard?
A used part from another vehicle will have the wrong programming and will not work in your truck without being reprogrammed by a dealer. Our modules are quality-tested and programmed specifically for your VIN, guaranteeing compatibility and proper function.