05-08 Ford F150 Freestar Mercury Monterey 3.9 & 4.2 Head Gasket Set Increasing torque and performance with decreasing consumption and emissions Withstand high and low temperatures to provide a reliable seal with minimal tightening Durable and Long-lasting withstand aggressive media, higher temperatures, lower component strength and higher deformation under mechanical stress Reducing the flow of oil through the cylinder-head into the combustion chamber Please see description details below to ensure the fitment