A lifter is a cylindrical component that sits between a cars camshaft and the cylinder valves. It is also known as a valve lifter or hydraulic tappet. The lifters role in the valvetrain is to transfer the motions of the cam lobe up through the pushrods and rockers to open and close the valves. The size and shape of the cam lobe under the lifter determines valve lift and duration. In pushrod engines, the lifter pushes the pushrod up to actuate the intake and exhaust valves. Hydraulic lifters were developed to eliminate the clatter produced by solid lifters because the valvetrain runs with zero lash (clearance).

Valve lifters are found in engines that use pushrods as part of the drivetrain. They help to control the combustion process by letting fuel in and exhaust out. When valve lifters wear out, the valves cant open or close properly, which reduces the amount of power the engine can produce. A faulty valve lifter may cause more noise at a higher speed and disrupt a cylinders ability to mix and burn air and fuel. If you find these symptoms in your car, it is recommended to repair it as soon as possible to save more money on car expenses.