I have a 98 Freightliner chassis with a Cummins 5.9 ISB. At 91,000 miles, and about 3 mile from destination camp ground in Lancaster Co. PA, the engine dropped a valve ruining the head, injector, piston and cylinder wall. Lucky for me as Cummins was giving a 7 yr warranty so they paid the bill. Two weeks after we drove our car home am ready to drive 600 mi back and retreive the rig. They valve broke at the weld holding head to stem. Just hope I can trust the engine for another 91,000 as by that time I will be ready for a new one, if I'm still able to enjoy the RV life. Roger