I found a workaround for now. Google maps has a "softer" setting. You have to be careful because if you take the phone to another car for navigation, it may not be loud enough. I have a strange feeling they did this on purpose and thought it was a good idea. To make sure you didn't miss an instruction.
Google maps yes, but I'm referring to the factory Uconnect built in navigation maps, it's just much too loud and we shouldn't have to adjust it every time we get in the truck!
I also use the speed limit warning, I have it set to warn me if I go 10 MPH over the speed limit, and I just about slam my head on the roof every time it goes off, and then I have to reach over and turn down the guidance volume again (which is often).