Like it was mentioned, it is the gettingin a HDT. My knees have been replaced, i was a owner operator w/ 1988 T600 KW . Loved the ride but my wife wont learn to slip shift and i refuse to own a computer dependant def pig. My tow vehicle is 2002 F350 4dr dw 8ft bed with 7.3 and 3 spd auto, daily driver is 03 f250 7.3 3 spd auto ext cabw/ 8ft bed. Spent a few years daily up n down from hdt cab. Nice ride but do not put 14 hr days in behind a windshield anymore. Rv is a 09 drv 36tk3. As any time u r on the seat watch, wait, plan and prepare