I have a 2015 GMC SLE but I only have OnStar Nav so no maps, such a big screen and I can't see a map...I'll be getting a RV Nav system anyway so I don't tow into a low bridge or propane restricted tunnel. Who invented OnStar Nav is not my fav person, just put a map in the truck and let me figure it out, I don't need to have someone to take my address and give me turn by turn directions.