I just purchased a 2021 Denali 3500 HD Crew Cab 1 ton truck in January. In February 2021, I encountered a issue of not being able to shift out of D (drive) due to snow/slush buildup where the skid plate protects the transmission gear shifter under the driver seat. The GMC dealer in Grangeville, Idaho looked at the shifter area and said to take the rig to the car wash to use the water sprayer to melt out the packed snow from around the shifter. Luckily I had a diesel guy with me on my travels to Boise, so he was able to spray the water up inside the skid plate area to melt the snow from the gear shifter, and then I was able to shift the transmission out of drive into the other gears (N, R, P). I was completely surprised as well as my associate when I pulled up into my storage unit in Grangeville that I could not shift out of drive to park the truck or reverse out of storage unit. I couldn’t take my foot off the brake and and it put me in a extremely dangerous situation.
I want to be clear that my driving up to Elk City occurred on State highways 95, 14 and on county roads that are plowed on a daily basis when snow storms frequent our state. The temperature in Grangeville that day was mid 40's. There was no other snow buildup under the truck. I was not off-roading in areas that were not plowed. My friend also owns a 2020 Denali 1ton up in elk city who bought their truck from Dennis Dillon. They have gotten their truck buried in snow that they had to get a piece of equipment to pull it out- and did not have any snow packed up in their skid plate area. My friend has not encounter this issue with their truck that I have experienced.
Has anyone also experienced similar issue where they could not shift their truck out of D gear? I am new to this forum and couldn't find any information related to the issue I experienced. If it is in a thread somewhere, can you point me in the right direction?