108k miles on my 2005 usually loaded at 19k lbs GCW. It has crossed the Rockies on three round trip vacations without ever a need for more power or more truck.
It has been towed once due to high pressure oil fitting failure but otherwise always got to our destination under its own power.
I have had less maintenance costs than a friend with a two year newer Dodge but know others that own any of the big three trucks and have had no issues after after 150k miles.