Restore Smooth, Reliable Shifting to Your Chevrolet Monte Carlo
If your 2006-2007 Chevrolet Monte Carlo is suffering from erratic shifting, getting stuck in gear, or throwing transmission-related trouble codes, the culprit is often a failing Transmission Control Module (TCM). As a technician with over two decades of experience, I’ve seen firsthand how a faulty TCM can mimic a major transmission failure, leading to frustrating and expensive misdiagnoses. This OEM-quality T42 TCM, part number 24255280, is the definitive solution to restore your vehicle’s performance and drivability.
The TCM is the brain of your automatic transmission, responsible for managing every gear change, controlling torque converter lockup, and monitoring sensor data. When it fails, communication breaks down, resulting in the harsh shifts and poor performance you’re likely experiencing. Our replacement module is a direct-fit solution, but with a crucial benefit: it arrives at your door fully programmed to your vehicle’s specific VIN. This eliminates the need for a costly trip to the dealership for programming, making it a true plug-and-play repair for both professional mechanics and DIY enthusiasts.
A Technician’s Notebook: The Misleading Limp Mode
I remember a 2007 Monte Carlo that came into the shop stuck in what we call “limp mode”—it wouldn’t shift out of 3rd gear. The owner was convinced his transmission was shot. The scanner showed a generic P0700 code (Transmission Control System Malfunction) and a few solenoid circuit codes. Instead of immediately quoting a transmission rebuild, we checked the basics. The fluid was clean, and the wiring looked good. We swapped in a known-good test TCM, and the car shifted perfectly. The original TCM had an internal short, causing the false codes and limp mode. This replacement 2006-2007 Monte Carlo TCM saved the customer thousands and got their car back on the road the same day.
Common Signs of a Failing Monte Carlo TCM
A failing TCM can cause a variety of symptoms that disrupt your driving experience. If you’re noticing any of the following, it’s a strong indicator that your module needs replacement:
- ✔ Harsh, jerky, or delayed gear shifts.
- ✔ The vehicle is stuck in a single gear (limp mode), often 2nd or 3rd.
- ✔ An illuminated Check Engine Light or Transmission Warning Light.
- ✔ Diagnostic Trouble Codes (DTCs) such as P0700, P0750, or other solenoid-related faults.
- ✔ A sudden drop in fuel economy.
- ✔ The transmission seems to slip between gears.
- ✔ Complete loss of communication with the transmission module.
A Straightforward Guide to Installation
One of the best features of this module is its simple installation. For the 2006-2007 Monte Carlo, the process is straightforward and can be done with basic hand tools in your own garage.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent electrical shorts and reset the system.
- Locate the TCM: On your Monte Carlo, the TCM is typically found underneath the lower air cleaner housing. You will need to remove the air cleaner assembly to access it.
- Disconnect and Remove: Carefully unplug the electrical connectors from the old TCM. Then, unbolt the module from its mounting bracket and remove it from the vehicle.
- Install the New Module: Mount the new, pre-programmed TCM in the same location and securely fasten it. Reconnect the electrical connectors, ensuring they click into place.
- Reassemble and Finalize: Reinstall the air cleaner housing. Reconnect the battery terminal. Start the vehicle and use a basic scan tool to clear any stored fault codes to complete the process.
Verified Vehicle Compatibility
This T42 Transmission Control Module is a direct replacement for part number 24255280 and is compatible with a wide range of General Motors vehicles. While this page is focused on the 2006-2007 Monte Carlo TCM, it also fits the following models. Always verify your part number for a perfect match.
- Chevrolet Monte Carlo: 2006-2007 (Transmission; lower air cleaner housing)
- Chevrolet Impala: 2006-2011 (Transmission; lower air cleaner housing)
- Chevrolet Cobalt: 2006-10 (Transmission; LH strut tower)
- Chevrolet HHR: 2006-11 (Transmission; LH engine compartment)
- Buick Allure/LaCrosse: 2006-2009 (Transmission; lower air cleaner housing)
- Pontiac G6: 2006-2010 (Transmission; LH strut tower)
- Pontiac Grand Prix: 2006-2008 (Transmission; lower air cleaner housing)
- And many other GM models listed in the original fitment data.
Frequently Asked Questions
Do I need to program this module?
No. We program the module to your vehicle’s VIN before shipping. It arrives ready for plug-and-play installation, with no need for a trip to the dealer or a special scan tool for programming.
Is there a core charge for my old part?
No, there is no core charge. You can keep your old part or recycle it locally without the hassle of sending it back.
What tools are required for installation on a Monte Carlo?
You’ll typically need a basic socket set and screwdrivers to remove the air cleaner assembly and unbolt the module. No specialized tools are required.
Will this fix a P0700 trouble code?
A P0700 code is a general fault request from the TCM to the main engine computer. While a faulty TCM is a very common cause, this code can also be triggered by other transmission issues. Replacing a confirmed-bad TCM will resolve the code.
How does the VIN programming work?
During checkout, you will provide your vehicle’s 17-digit VIN. Our technicians use this information to load the latest GM-certified software and calibration files directly onto the module, ensuring it communicates perfectly with your car’s specific systems.