Heh, I havent met a 4 cylinder yet that doesnt have head gasket probs between 60 and 90K. Its been explained to me that because the head is make of aluminum and the block out of cast iron, the two metals do not maintain the same temperature..causing a warp of the aluminum..or eventual head crack if the head isnt taken off and trued before you crack it. Never could figure out why they just dont make both out of the same metal if they know its a prob.