Many on here consider the 7.3 motor the best diesel motor produced until the 6.7 recently came around. Only issues I can think of is a sensor with a long tube that occasionally gets clogged with soot and needs to be blown out. Other issue that's also a cheap fix is the cam sensor. Then there's the "quarter" shim to ensure that the injector wiring harness in the heads doesn't un-seat from the wiring clip. Really, all the issues around this engine are cheap fixes. Only thing pricey that was previously mentioned is the transmission. But at 75k miles and good maintenance, I would figure you had another 75k miles minimum. There are many on this forum that would buy the vehicle if you don't :).