5258739
Engine Piston ( Standard ) Kit
Cummins®

A Standard Engine Piston Kit is a set of components that includes the piston, piston rings, and wrist pin. The piston is a cylindrical piece that moves up and down within the cylinder of an engine. It is responsible for compressing fuel and air in the combustion chamber during the compression stroke, and then transferring energy to the crankshaft during the power stroke. The piston rings are small metal bands that fit around the circumference of the piston to help seal it against the cylinder wall and prevent oil from entering into combustion chamber. The wrist pin connects the piston to a connecting rod, which in turn connects to the crankshaft. When replacing or rebuilding an engine, it is often necessary to replace these components together as a kit. Part number 5258739 specifies a specific standard engine piston kit designed for use in certain make and model trucks.