Every vehicle has a combination of springs and either struts or shocks for the front and rear suspension. The springs act as a support for the vehicles wight and also provide “cushion” to the vehicles ride. This cushion of the springs helps to reduce the jarring effect of driving over pavement irregularities in the road.
Because of the rate of expansion between cylinder heads metal and valve covers are different every car will need valve cover gaskets replaced at least once in it’s lifetime. The seal/gasket will break down over time and your engine will leak oil from here. Valve cover gaskets are typically made of a cork/paper composite or