Real-World Repair Story
Real-World Repair Story
A customer brought in his 2016 Sierra 2500 HD with the 6-speed Allison. His complaint was vague—’it just shifts hard sometimes,’ especially on the 2-3 upshift, and he had an intermittent check engine light. A quick scan pulled a P0700, which is just a general transmission fault request, but digging deeper, we found a U0100 for lost communication. After checking the wiring harness and connectors for the classic signs of corrosion or damage (they looked pristine), we suspected the TCM itself. Instead of a costly diagnostic path, we recommended this pre-programmed module. The swap took less than an hour, and the truck’s shifting was immediately crisp and smooth. The communication code vanished. It was a perfect example of how a reliable, correctly programmed 2015-2016 Sierra Denali 2500 TCM can solve what seems like a major powertrain issue.
Frequently Asked Questions
No. We program the module to your vehicle’s specific VIN before shipping. It arrives ready for installation, saving you a trip to the dealership.