Restore Flawless Shifting to Your Chevy HHR
If your 2006-2011 Chevrolet HHR is suffering from harsh shifting, getting stuck in gear, or throwing transmission-related check engine lights, you’ve likely pinpointed the culprit: a faulty Transmission Control Module (TCM). As a seasoned technician, I’ve seen countless GM vehicles, including the HHR, sidelined by these exact issues. This T42 TCM, service part number 24252114, is the definitive, hassle-free solution. It arrives expertly programmed to your vehicle’s specific VIN, making it a true plug-and-play component that restores the crisp, predictable shifting you expect from your car.
A Technician’s Notebook: The Intermittent HHR Shifting Puzzle
A customer brought in their 2009 HHR with a frustrating problem: sometimes it would shift perfectly, other times it would refuse to shift out of 2nd gear and the transmission warning light would pop on. They had already replaced a shift solenoid with no luck. After connecting my scan tool, I saw the classic P0700 (Transmission Control System Malfunction) code, but the solenoid codes were intermittent. Based on over 20 years of experience, I knew these symptoms often pointed not to the transmission internals, but to the module itself. Heat cycles and vibrations can cause internal solder joints in the TCM to fail over time, creating these ghost-in-the-machine issues. Installing a new, pre-programmed 2006-2011 HHR Transmission Module solved the problem permanently. The customer was back on the road the same day without a single shifting issue.
Is Your HHR Exhibiting These Transmission Faults?
A failing TCM doesn’t always mean a complete transmission failure. Often, the signs are electronic. Watch out for these common indicators that your module needs replacing:
- ✔ Abrupt, harsh, or delayed gear shifts.
- ✔ Vehicle is stuck in “limp mode” (usually second or third gear).
- ✔ The Check Engine Light or Transmission Warning Light is illuminated.
- ✔ Diagnostic Trouble Codes (DTCs) are present, such as P0700, P0750, P0753, P0758, or other solenoid-related faults.
- ✔ A sudden drop in fuel economy.
- ✔ Inability to shift into higher or lower gears.
Your Step-by-Step HHR TCM Installation Guide
One of the best features of this module is its straightforward installation. You don’t need a lift or specialized transmission tools. For the Chevy HHR, the job can be done in under 30 minutes with basic hand tools.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the Module: On the 2006-2011 HHR, the TCM is found in the left-hand (driver’s side) engine compartment, typically mounted near the strut tower.
- Disconnect and Remove: Carefully unclip the electrical connectors from the old module. Then, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new VIN-programmed TCM into place. Firmly reconnect the electrical connectors, ensuring they click securely into position.
- Final Steps: Reconnect the negative battery terminal. While the battery disconnect often clears codes, it’s best practice to use a basic OBD2 scan tool to clear any stored DTCs from the system. Start the vehicle and test drive to confirm smooth shifting.
Verified Vehicle Compatibility
This T42 TCM is a direct replacement for a wide range of General Motors vehicles. While this page is dedicated to the 2006-2011 HHR Transmission Module, it is also compatible with the following models and locations:
This part will fit these makes and models with these options:
AURA 07-09 Transmission; (LH frame rail front)
AVALANCHE 1500 07-08 Transmission; (next to battery)
CANYON 08-12 Transmission; (RH rear engine compartment)
COBALT 06-10 Transmission; (LH strut tower)
COLORADO 08-12 Transmission; (RH rear engine compartment)
DTS 06-11 Transmission; (RH front engine compartment)
ENVOY 06-07 Transmission; (LH engine compartment), (8 cylinder)
ENVOY 08-09 Transmission; (LH engine compartment)
EXPRESS 1500/2500/3500 VAN 06-14 Transmission; (RH engine compartment)
G5 07-10 Transmission; (LH strut tower)
G6 06-10 Transmission; (LH strut tower)
GRAND PRIX 06-08 Transmission; (lower air cleaner housing)
HHR 06-11 Transmission; (LH engine compartment)
HUMMER H3 08-10 Transmission; (RH rear engine compartment)
IMPALA 06-11 Transmission; (lower air cleaner housing)
ION 06-07 Transmission; (behind LH strut tower)
LACROSSE/ALLURE 06-09 Transmission; (lower air cleaner housing)
LUCERNE 06-11 Transmission; (LH engine compartment)
MALIBU 06-10 Transmission; (LH frame rail)
MONTE CARLO 06-07 Transmission; (lower air cleaner housing)
MONTANA 06-09 Transmission; (LH strut tower)
SAAB 9-7X 06-09 Transmission; (LH engine compartment)
SIERRA/SILVERADO 1500/2500 07-13 Transmission; (next to battery)
SSR 05-06 Transmission; (front LH frame)
SUBURBAN 1500 07-08 Transmission; (next to battery)
TAHOE 07-09 Transmission; (next to battery)
TERRAZA 06-07 Transmission; (LH strut tower)
TRAILBLAZER 06-09 Transmission; (LH engine compartment), (8 cylinder models)
UPLANDER 06-09 Transmission; (LH strut tower)
VUE 07-10 Transmission; (LH front engine compartment)
YUKON/YUKON XL 1500 07-09 Transmission; (next to battery)
Note: Location notes are for general guidance. Always confirm the location on your specific vehicle.
Frequently Asked Questions
What does ‘VIN Programmed’ mean for me?
It means we load your vehicle’s unique Vehicle Identification Number (VIN) and the latest GM software onto the module before shipping. This ensures it communicates perfectly with your HHR’s engine computer and other systems right out of the box, with no expensive trip to the dealership required for programming.
Will this fix a P0700 code on my Chevy HHR?
A P0700 code is a general fault request from the TCM to the main engine computer. While this module often resolves the root cause (like a faulty solenoid driver circuit inside the TCM), you should always diagnose any other specific transmission codes (like P0753) that are present to ensure there are no other issues. In many cases, a new TCM is the correct fix.
Can I install this myself if I’m not a professional mechanic?
Absolutely. For the HHR, this is a very DIY-friendly repair. The module is easily accessible in the engine bay, and the replacement process involves simple unbolting and unclipping. Following our guide above, most people can complete the job in under 30 minutes.
Do I need to send my old part back?
No, there is no core charge for this part. You can keep or dispose of your old module without any hassle or extra fees.
What kind of warranty is included?
This module is backed by our one-year, hassle-free warranty, giving you confidence and peace of mind in your repair.