I just bought a 01 with 225,000 on it. the truck is really nice and price was good. how many miles is to many? I asked Cummins the same thing and they said to change oil and put it to work.

 

it all depends on the maintainence of the rig, that mileage on a well taken care of cummins is prolly 30% wore out at most, in the care of a nincompoop it could be bandaided together now. totally variable, but over all they are very tough engines. capeable of a million miles, but you will buy a fuel pump and tranny well before that.