Hoses are frequently overlooked in normal maintenance. Both upper and lower radiator hoses and all heater hoses should be checked for deterioration, leaks and loose hose clamps at every tune-up. Check the hoses by feel; they should be pliable. Any hose that feels hard or brittle should be replaced as soon as possible; in any case, replace radiator hoses as necessary every two years or 30,000 miles (48.000 km).