Two problems related to power train have been reported for the 2018 GMC Sierra 2500. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2018 GMC Sierra 2500 based on all problems reported for the 2018 Sierra 2500.
While trying to merge onto the insterstate my truck started lost power and started to chug. My truck slowed drastically which caused a tractor/trailer to almost run into the back of me. This has been an ongoing issue that my dealership has addressed by reflashing my computer. To my knowledge the first flash was for the transmission and the second time was for the fuel injectors. The reprogramming has not fixed the issue. I was trying to merge with traffic on I 80 in utah.
Truck began rolling downhill while the vehicle was in park with the keys out of tge ignition. I was removing a child seat from the passenger side rear seat at the time. Spouse was able to hurriedly jump into the vehicle and apply the brakes.