Hobbies Cars & Motorcycles How to Add Windshield Washer Fluid to Your Vehicle Share PINTEREST Email Print Birdlkportfolio / Getty Images Cars & Motorcycles Cars How Tos Basics Reviews Classic Cars Corvettes Mustangs Tires & Wheels Motorcycles Used Cars Trucks ATVs & Off Road Public Transportation By Benjamin Jerew Benjamin Jerew Benjamin Jerew is an ASE-certified Master Automobile Technician with over a decade of experience in auto repair, maintenance, and diagnosis. Learn about our Editorial Process Updated on 05/24/19 Your windshield serves at least a couple of important functions: keeping the wind and elements out of your face while giving you a clear view of the road ahead. Unfortunately, the windshield rarely stays clean for long, as dust, dirt, pollen, and bugs collect on it. Windshield wipers are good for keeping the windshield clear in the rain, but can’t really do much when the windshield is dry. To clean the windshield on the road, a couple of squirts from the windshield washer usually suffices to wet the windshield enough for the wipers to clear it. When you activate the windshield washer, usually via a button or lever, an electric pump sends pressurized washer fluid from the reservoir to the windshield. Usually, a couple of jets on the hood or under the hood spray washer fluid on the glass, but some systems send washer fluid through a tube on the windshield wiper arm. Some systems might activate headlight washers at the same time to clear dust from the headlights. In the winter, some systems use a washer fluid heater to improve frost removal and prevent frost formation. What Does Windshield Washer Fluid Do? Water, the “universal solvent,” can sometimes keep your windshield clear, but causes problems. First, if you live in a cold climate, plain water will freeze. Even if it doesn’t damage the reservoir, pump, tubes, or spray heads, it won’t do anything to remove winter grime from your windshield. If you can’t see clearly, you could get into an accident. Second, in a warm climate, plain water will breed bacteria. The use of plain water as “washer fluid” has also been linked to Legionnaire’s Disease, according to a UK study, caused by breathing in aerosolized Legionella bacteria. Whether to prevent disease or improve visibility, using windshield washer fluid is suggested over plain water. Windshield washer fluid, also called windshield wiper fluid, washer fluid, washer solvent, or wiper fluid, isn’t simply water. A mixture of water, solvents, alcohol, and detergents, washer fluid is specifically formulated to dissolve road grime and dead bugs and wash away dust and dirt. With a good pair of windshield wiper blades – you should replace them about once every four to six months – you should be left with a clear windshield and a streak-free shine, for maximum visibility and minimum glare. What Kinds of Windshield Washer Fluid Are There? We’ve already covered what windshield washer fluid is and is not, but it’s also good to know that there are different formulations, depending on the situation. Some of these you simply add full-strength to the reservoir, while others can be diluted to fit the application. “All-Season” fluid is just that, formulated to work pretty much everywhere you drive and any time of year. In spring, summer, and fall, you can dilute it up to 1:10 with distilled water – distilled water won’t leave water spots like tap water will. In Winter, use washer fluid full-strength to prevent freezing.“Bug Remover” contains higher concentration of solvents and detergents to break up and dissolve dead bugs on your windshield. In some locations more than others, bugs are a major problem, but bug-specific washer fluid makes quick work of them.“Winter” or “De-Icer” types typically contain more alcohol, such as ethanol, isopropanol, or ethylene glycol. These additives reduce the freezing point, preventing freezing and keeping your windshield frost-free. If you’re heading into Winter, fill up with a winter blend before temperatures drop. How to Add Windshield Washer Fluid Besides discovering that you’re out of the stuff when you need it most, how do you know when to add washer fluid? One of the first indicators is a warning light on your dash, but not all vehicles have a low windshield washer fluid warning light. In that case, you’ll have to consult your owner’s manual to determine the location of the washer fluid reservoir, usually under the hood somewhere – some vehicles with rear washers have a separate reservoir in the rear. Under the hood, the washer fluid reservoir is usually labeled with a unique icon, colored cap, or both. Blue is a common color, since washer fluid is typically blue, but don’t rely on color alone. Always check the owner’s manual for proper location and icon. Once you’ve identified the washer fluid reservoir, you may be able to see fluid level simply by looking at it, but not all are translucent or even visible. Some hidden types are equipped with a dipstick, but not all. To add washer fluid to your vehicle, open the washer fluid reservoir cap, pour in washer fluid until it reaches the top, and replace the cap. Don’t worry about mixing types, such as in between seasons, as washer fluid types are universally compatible. It’s always a good idea to keep a gallon of washer fluid on hand, and top it off once a week. During certain seasons, you’ll use more washer fluid than normal. Running out could leave you practically blind. Keep a gallon of washer fluid in your car during those seasons. Washer Fluid Helps You Drive More Safely Everyone can agree that, if you cannot see, you cannot drive safely. Keeping watch on your washer fluid level, using the right type, and with a good set of wiper blades, you take care of your visibility. The better you can see, day or night, rain or shine, bugs or dust, the more prepared you’ll be to react to ever-changing circumstances on the road. Have you topped off your washer fluid lately? If not, maybe today is a good day to do it.