I have a 2020 Silverado 3500 diesel with about 25,000 miles on it that started having transmission issues with the reduced engine power warning along with the transmission shuttering and then refusing to shift gears. All of that would go away when the truck was turned off and restarted. I took it to the dealership expecting a warranty repair.
They finally got it in and I missed the call today but the service rep left a message and said that there were some transmission sensor issues but they also found significant water in the transmission and he said that that problem was not covered by warranty.
First off how the heck does water get into a transmission that doesn't even have a dipstick. And secondly how is this not covered under warranty? I am the only person to drive this truck and I've never driven it through more than a puddle. I am hot to say the least and unless someone on here can point me to a mistake that I made causing this I'm going to be in as many peoples ear tomorrow until they agree to cover this repair.