Just got my 2020 Duremax and took it camping over the weekend. It rained on us and I ended up having to put it into 4 low to get out. The transmission made this horrible noise as soon as I put it in to park. It would only happen going in to park while in 4 low. Dealership has no idea what is going on. There is an identical truck on the lot that has the same thing happening. Not even 500 miles yet, so I hope they get it figured out.