Why don’t all cars have a rear windshield wiper? A number of factors go into the decision, like fuel economy and aerodynamics.
Why Don’t All Cars Have a Rear Windshield Wiper?
Updated on May 23, 2025
In poor weather conditions a rear windshield wiper provides clear vision through your rear view mirror’s line of sight. As a bonus, it usually allows for the incorporation of a washer-fluid dispenser that can improve vision in dry conditions, too. Rear wipers come standard on SUVs and many hatchbacks, but why don’t all cars have one?
Is a Rear Windshield Wiper Even Necessary?
Many opinions exist regarding the absence of rear windshield wipers on sedans. Some claim that because of the aerodynamics of a sedan, it doesn’t require one: Windshear alone does a fine job of driving water, snow and debris from the surface of the glass.
Others point to the body style: The length of the trunk compartment acts as a buffer between the wheel spray and the window, preventing it from settling on the glass.
Another opinion returns to aerodynamics, suggesting that air movement over the top of a sedan would lift the wiper from the surface of the glass, making it useless.
Rear Windshield Wiper Manufacturing Considerations
There are all sorts of possible reasons that car makers might choose to leave off a rear windshield wiper. Some that top the list: Lack of space to conceal a rear windshield wiper motor and washer-fluid reservoir, the added cost of the system, weight reduction considerations (to meet fuel-efficiency standards), increased drag (which disrupts aerodynamics, and once again, fuel efficiency) and cosmetic appeal.
Rear Windshield Wiper: The Final Word
The most satisfying answer in the end? Because the car designer decided not to put one there. Exactly why they made that decision could well have to do with any of the speculations above, as determined by their unique set of traditions, values and sensibilities.
FAQ
How often should I replace my rear windshield wiper?
At least once a year, but ideally every six months. It can also prolong their life if you invest in quality blades that have coatings to help them last longer and perform better in tough weather can help keep you safer on the road.
“People assume rear blades last longer because they’re used less, but the back window actually gets more sun exposure, which can wear the rubber down faster,” says Watson.
How do I clean the rear windshield wiper?
Dirt, dead insects and tree sap, can quickly destroy the wiping elements on your blades, so regular cleaning will help prolong the life of your wipers, plus increase your visibility and safety. To clean a wiper:
- Gently lift up the wiper arm.
- Wipe the blade and arm with a soft cloth and warm, soapy water.
- Rinse and dry.
- Clean the glass with a non-ammonia glass cleaner to prevent haze.
“Do not use any cleaners that have alcohol or bleach, such as regular dish soap, as that can strip wax and even damage paint,” says Watson. “Instead a dedicated windshield or car wash soap.”
About the Expert
- Duane “Doc” Watson is a technical trainer at Bosch Mobility Aftermarket. He has more than 45 years of experience in automotive repair, has trained thousands of technicians and earned many industry awards, including Chevrolet Technician of the Year and Buick Service Master of the Year.
