Ibought a second hand jeep in 2004, previous owner indicated that the vehicle had used coolant before - and was repaired by chrysler(replaced head gasket), 18000km's after this job I sit with 5 cracked heads (heads are seprate for each piston), I keep hearing "this is a common problem" but nothing official.Has anyone had similar problems, if so I'd like to know what the cause is, as its pretty expensive repairing and I wouldn't want to redo this after the next 18000 km's.The vehicle never overheated my problem starte when it started using coolant and I noticed oil in the coolant.