Formulated to remove grime and bugs, windshield washer fluid is a mixture of solvent, detergent and antifreeze agents. Used in conjunction with a pump and windshield wipers, washer fluid can be sprayed onto the windshield when the vehicle is in motion or stationary.
Sold in various formulas, all washer fluids have some type of antifreeze agent, such as methylated spirits, to prevent the fluid from freezing in the reservoir, pump and tubing in colder climates. Types of detergents in washer fluid vary, with some formulas being sold as “Bug and Tar Remover,” “Deicer” or as an “All-Season” formula.
Some washer fluids are designed to be diluted with water, whereas others are intended to be used full strength and others are sold in powder form to be mixed by the consumer. When water is added, distilled water is recommend for mixing with washer fluid as tap water often contains minerals that can clog washer jets and leave deposits on glass.
With billions of gallons of washer fluid being sold every year, environmental groups have voiced concerns over the use of chemicals in washer fluid as, ultimately, anything sprayed on a car windshield ends up in the water table. Additionally, chemicals added to washer fluid to prevent freezing and are harmful when inhaled, a concern whenever toxic substances become aerosolized. Because of this manufactures have begun using less toxic isopropanol alcohol to prevent winter freeze ups. Some consumer advocacy organizations have also voiced concerns about the effects of the solvents and antifreeze products in washer fluid on the car’s finish, causing damage to paint, chrome and introducing corrosion. Because of these issues, many drivers in warmer latitudes choose to use water instead of washer fluid. However, substituting plain water for windshield washer fluid has both pros and cons.
Using water in place of windshield washer fluid will save money and reduce pollution, but can potentially cause hundreds of dollars of damage, should the system be subjected to freezing temperatures when filled with only water.