Why is one wiper blade longer than the other?

Windshield wipers are responsible for cleaning the visible area on the windshield. They swipe back and forth to remove rain, snow, ice, mud and other debris. Their main purpose is to enable the driver to…

Windshield wipers are responsible for cleaning the visible area on the windshield. They swipe back and forth to remove rain, snow, ice, mud and other debris. Their main purpose is to allow the driver to see as much of the road and surrounding traffic as possible.

Clear visibility is achieved by shifting the hinges of the wiper blades. When you look at the windshield, the wiper pivots are not centered on the glass. They are both mounted to the left, and the passenger side wiper is closer to the middle of the windshield. When the wipers are on, they swipe up, then stop and reverse when they reach a position just behind the vertical. The wiper blade on the driver's side is long enough not to touch the upper windshield molding or the edge of the glass. The passenger side wiper blade comes as close as possible to the passenger side windshield to clear as much of the area as possible.

In order to maximize the space to be swept, wiper blades typically come in two different sizes depending on exactly where the wiper pivots are located. In some designs, the driver's side is a longer vane and the passenger's side is a shorter vane, while in other designs it is inverted.

If you are replacing your wiper blades, make sure you use the same size as specified by your vehicle manufacturer to provide the best visibility for the driver.