Bumpers
They restrict the movement of connected elements. They keep them at the right distance. They prevent harmful effects and increase driving comfort.
This is a brief description of the different types of bumpers usually made from rubber. They are used, in particular, in 
car doors, under the hood, in the trunk and in the suspension. Door bumpers and lids are designed in such a way that they are energized when they are closed. This ensures that the movable cover is held better, it cannot vibrate causing noise, and once the latch is released, the bumper spring makes it easier to open. In the case of some bumpers (especially those installed under the hood and trunk), solutions are used to change their height and therefore the spring force.
In suspension, bumpers, i.e. compression stroke limiters, limit the deflection of leaf springs, coil springs or arms associated with torsion bars when they are compressed, absorbing large forces in a small way. Elastic cushions serving this purpose can be placed in shock absorbers, inside the helical spring, as well as on the axle housing. In addition to the compression limiters, there are also elements that limit the downward movement of the wheels, i.e. when stretching the suspension. In most solutions, the pillows of these stops are located in shock absorbers or guide columns. Flexible materials are also used as additional spring elements. Compared to conventional travel stops, the suspension travel is much higher and has a softer feel. Made from rubber or polyurethane elastomer. The air in the pores of the elastomer is compressed when the elastic element is deformed, which allows it to transmit large compressive forces. The combination of a steel spring with an appropriate additional spring element allows almost any suspension stiffness characteristics to be obtained.
Bumpers are mechanically damaged or lose elasticity as a result of the gradual aging of the material from which they are made.
It is better to replace damaged bumpers as a set, since at the points of contact we have elements with the same elastic properties. In the case of adjustable fenders, the negative effects of the progressive aging of the material can be reduced, at least in part, by changing their active height.
