Truck was extremely well maintained its whole life. Noticed there was no coolant not the radiator and no visible leaks. The coolant had been flushed on time, had thermostat replaced, water pump and radiator. Truck never ran hot. So I took it in for a block test and sure enough the shop says there is a small leak in the head gasket that's gonna get worse if I keep driving it. Shop said it would be $2200 to fix!! It showed no reason to have a blown head at such low miles!