EXPANSION TANK HOSE
Expansion Tank Hose : Simply the hose(s) that connects to the expansion tank. A typical expansion tank setup is a hose that feeds coolant into the engine and a hose that lets the air escape to the top of the expansion tank. These hoses are made of reinforced rubber and are designed to hold the heat of the engine coolant. If the expansion tank hose looks swollen, gets soft or leaks, it must be replaced.