Restore Smooth Shifting to Your 2007-2008 Chevy Avalanche 1500
If you’re dealing with the headache of a transmission that won’t shift correctly, you’re not alone. As a technician with over two decades of experience, I’ve seen countless GM trucks, like your Avalanche, come into the bay with symptoms that point to a failing Transmission Control Module (TCM). Harsh bangs into gear, getting stuck in limp mode, or a persistent check engine light can make you think the entire transmission is shot. But often, the real culprit is this small electronic brain. This T42 TCM, part number 24241806, is the reliable, cost-effective solution you need. It comes fully programmed to your vehicle’s specific VIN, so you can skip the expensive trip to the dealership and get your truck running right again.
Case Study: The Avalanche That Dodged a $4,000 Repair Bill
A customer brought in his ’07 Avalanche, convinced he needed a full transmission rebuild. It was stuck in 3rd gear, and he’d been quoted thousands elsewhere. After hooking up my scan tool, I saw the classic P0700 and a few solenoid circuit codes. Instead of jumping to the worst-case scenario, I checked the TCM. Sure enough, it was failing. We swapped in a VIN-programmed module just like this one. In under an hour, the truck was shifting like it just rolled off the factory floor. He saved a fortune and a ton of downtime—all because we correctly identified the electronic failure instead of a mechanical one.
Is Your Avalanche Showing These Symptoms?
A faulty TCM can manifest in several ways. If you’re experiencing any of the following, this module is likely the solution for your 2007-2008 Avalanche 1500 TCM issues.
- âś” Unpredictable or harsh gear shifts.
- âś” The vehicle is stuck in a single gear (often called “limp mode”).
- âś” Delayed engagement when shifting from Park to Drive or Reverse.
- âś” Check Engine Light or Transmission Warning Light is on with codes like P0700, P0750, P0753, P0758.
- âś” Poor acceleration and a sudden drop in fuel economy.
- âś” The transmission seems to slip out of gear while driving.
A Straightforward Guide to Installation
One of the biggest benefits of this module is its simple, plug-and-play installation. No special programming tools are required. For the 2007-2008 Avalanche, the TCM is easy to access.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the Module: On your Avalanche, the TCM is typically located in the engine bay, right next to the battery.
- Disconnect and Remove: Carefully unclip the electrical connectors from the old TCM. Then, unbolt the module from its mounting bracket.
- Install the New TCM: Mount the new module onto the bracket and securely re-attach the electrical connectors. You’ll hear a click when they are properly seated.
- Final Steps: Reconnect the battery terminal. While the module is pre-programmed, it’s good practice to use a basic OBD2 scanner to clear any stored fault codes from the vehicle’s memory.
Verified Vehicle Compatibility
This T42 TCM 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 it is the specified part for the 2007-2008 Avalanche 1500 TCM, it also fits the following models. Please verify your specific application.
- AVALANCHE 1500 07-08 Transmission; (next to battery)
- TAHOE 07-09 Transmission; (next to battery)
- SILVERADO 1500 PICKUP 07-13 Transmission; (next to battery)
- SIERRA 1500 PICKUP 07-13 Transmission; (next to battery)
- YUKON 07-09 Transmission; (next to battery)
- SUBURBAN 1500 07-08 Transmission; (next to battery)
- YUKON XL 1500 07-08 Transmission; (next to battery)
- EXPRESS / SAVANA VANS 1500/2500/3500 06-14 Transmission; (RH engine compartment)
- ENVOY / TRAILBLAZER 06-09 Transmission; (LH engine compartment)
- HUMMER H3 08-10 Transmission; (RH rear engine compartment)
- COLORADO / CANYON 08-12 Transmission; (RH rear engine compartment)
- IMPALA / MONTE CARLO 06-11 Transmission; (lower air cleaner housing)
- And many more GM models from 2006-2014.
Frequently Asked Questions
Do I need to get this programmed by a dealer?
No. We program the module to your vehicle’s VIN before shipping. It arrives ready for installation, saving you time and hundreds of dollars in dealership fees.
Is there a core charge for my old part?
No, there is no core charge. You can keep your old module or recycle it locally without the hassle of sending it back.
What tools do I need for installation?
Basic hand tools are all that’s required. Typically, you’ll just need a socket wrench to disconnect the battery and unbolt the module bracket. The electrical connectors are removed by hand.
Will this fix a P0700 trouble code?
A P0700 code is a general transmission fault request, meaning the TCM has detected a problem and asked the main computer (ECM) to turn on the check engine light. If the underlying issue is a faulty TCM, replacing it will resolve the reason for the P0700 code.
What if my shifting problems continue after installation?
While this module fixes the vast majority of electronic shifting issues, persistent problems could indicate a mechanical issue within the transmission itself, such as worn clutches or a faulty valve body. However, replacing the TCM is the most critical and common first step in the diagnostic process for these symptoms.