The radiator cap is more than a cap for your radiator; it keeps your engine cool by sealing and pressurizing the coolant inside it. It is designed to hold the coolant in the radiator under a ...

A radiator cap functions as a two-way check valve. As the coolant heats and expands, a valve in the cap allows the coolant to flow out.

A bad radiator cap can lead to your truck developing overheating problems and potentially land you with expensive repair bills.