How come sedans don't have rear window wipers?

Question

Both SUV's/vans/wagons whose rear windows are more vertical than sedans, and hatchbacks whose rear windows are more horizontal, have rear window wipers. I'd think sedans, being in the middle, should have them too.

Answer 1

Basically because the aerodynamics.
An sedan vehicle make the rear wiper unnecessary because the car have an better airflow around it, this make the airflow to "clean" the rear window from water and debris at high speeds, but hatchbacks, SUVs and wagon vehicles have the rear wiper because of their shapes that produce behind them a big turbulent zone. This turbulence zone avoid the airflow to "clean" the rear window, and can even lift some debris (like dust and small stones) from the ground when the car is passing by.
Some sedans have an rear wiper like some versions of the Mitsubishi Evolution (like the one in this photo http://img150.imageshack.us/my.php?image=dscf0065tg0.jpg ), but it isn't very usual to see this kind of thing.

Answer 2

Because the rear window is far enough forward that it doesn't get a lot of dirt thrown up from the road. The early wagons (first with a vertical rear window all the way back) didn't have wipers nor did vans. After a while as people complained about the safety aspect the manufacturers started supplying rear wipers on the vehicles where the rear window was just above the bumper.

Answer 3

commonly, street-spray out of your rear tires covers the rear window of the motor vehicle whilst there is not any longer a trunk. SUVs and mini-trucks are exceedingly undesirable for this. The wiper is for squeegying off the grimy mist that accumulates, no longer for defogging.

Answer 4

Thanks for asking this question. I was perplexed about this too. It's also not a feature you find on sedans or other vehicles because consumers aren't demanding this feature.

The aerodynamics have a lot, if not everything to do with why sedans don't have rear window wipers.