Description
2008 GMC Sierra 6.6L TCM Transmission Control Module – Programmed Plug & Play
This Transmission Control Module (TCM / TCU) is a genuine OEM replacement for all 2008 GMC Sierra 6.6L models. Each unit is pre-programmed to your vehicle’s VIN and updated to the latest manufacturer calibration for a true plug-and-play installation with no dealer visit required.
Built to OEM standards for reliability, shift quality, and long-term performance.
Strict Testing & Quality Assurance
Each TCM is fully refurbished, bench-tested, and inspected by our certified in-house technicians.
We use professional off-board testing equipment to verify:
Proper CAN-bus communication
Shift-solenoid activation
Input/Output sensor signal validation
Temperature and load simulation
Live-data performance under simulated driving conditions
No module leaves our facility without passing a full quality control inspection. This ensures you receive a unit that performs better than new at an unbeatable value.
Common Symptoms of a Faulty TCM
Hard shifting / delayed shifting
Gear slipping
Stuck in Limp Mode
Transmission overheating
Erratic gear changes
Poor fuel economy
Trouble codes related to shift solenoids or communication
Contact Us
Email: info@fixecm.com
Phone: Local: 647-247-8555 | Toll-Free: 1-800-915-5566
Robert Brown –
This transmission control module was exactly what my 2008 GMC Sierra needed. It arrived quickly and was pre-programmed, which made installation straightforward—no extra setup required. The truck shifted smoothly after the swap, and I really appreciated the support offered when I had a quick question. Highly recommend for anyone looking to replace their TCM hassle-free.
Patrick Miller –
This module arrived quickly and installed easily—my Sierra is running smoother than ever! Highly recommend for anyone needing a reliable TCM replacement.
Nicholas Evans –
The plug-and-play setup made installation a breeze, and the free shipping was a great bonus. Fast service and the transmission shifts perfectly now.