A thrust bearing is a rolling bearing. Although they allow rotation between parts similar to other bearings, thrust bearings are primarily designed to support axial loads.
Thrust bearings help reduce friction and cope with stress while enabling rotational or linear motion between the various components of the car and other machinery.
Metal-to-metal contact creates a large amount of friction and stress in the metal. This friction usually increases the premature wear of the metal while slowly degrading it.
The main function of the thrust bearing is to reduce this friction and allow the metal parts to work smoothly, thus extending their durability.