Keeping your windshield washer fluid levels topped up is essential to your car’s maintenance and, therefore, your safety. But, if you want to buy washer fluid for your vehicle, how much should you buy and where should you buy it from? Or, can you just pour in water instead?
The average empty windshield washer reservoir can hold between 1 and 1.5 gallons of fluid. Some smaller cars hold as little as half a gallon of washer fluid, while some full-size pickups and SUVs can hold about 1.7 gallons.
To avoid spillage, it’s best to not fill up the reservoir above three-quarters capacity.
Most of the time, you will not need the total amount of fluid to fill the reservoir because some liquid might be left in the hoses leading to the windshield (or rear window and headlight washers if your car has that functionality). Below is some more information on how much windshield wiper fluid some popular cars hold and whether you can use regular water in its place.
Windshield Washer Fluid Capacities
The amount of windshield washer fluid each car holds differs between brands and models. Smaller cars will have smaller windshield wiper fluid reservoirs because of their limited space under the hood. Conversely, bigger trucks and SUVs will have room for larger reservoirs, which is just as well because the windshields are larger, too.
Usually, windshield washer fluid reservoirs can hold about three-quarters to a quarter of a gallon of fluid. Bigger cars or those with headlamp cleaners have reservoirs with a capacity of one-and-a-half gallons. Pickup trucks and SUVs have reservoirs of as much as 1.7 gallons. However, if you need to fill up the washer fluid, you will probably need less than the total capacity.
Below is a table showing the capacity of windshield wiper fluid reservoirs in some popular cars:
|Approx. Capacity of Washer Fluid Reservoir
|1 to 1.5 gallons
|1 to 1.5 gallons
|Tesla Model Y
|Dodge Ram 1500
How to Check the Capacity of Your Washer Fluid Reservoir
You can read the car’s owner’s manual to check how much windshield wiper fluid your vehicle needs. Alternatively, you can open the hood and see if your wiper fluid needs a top-up.
Most cars’ washer fluid reservoir is close to the windshield base. However, in vehicles like the Mazda CX-5, it is at the front part of the engine compartment close to the grille. Usually, the reservoir is white or translucent, meaning you can see the level of the fluid inside it. In addition, the cap of the reservoir will have a windshield washer symbol on it.
Suppose you need clarification on the location of the reservoir. In that case, you can check the car’s manual for its location or search the internet using your car model and year of manufacture.
Many modern cars have sensors that warn you if your windshield washer fluid level is low. If your vehicle isn’t one of those, you can check if your reservoir has external level markers to help you see the amount of fluid inside. If there are no external markers, you can check the fluid level by opening the reservoir cap and looking inside.
If your windshield wiper fluid reservoir is less than half, you should top it off (preferably with a funnel) at your earliest convenience. Additionally, your car should be parked on a level surface, and the engine should be cool before checking and refilling the washer fluid reservoir.
How Much Windshield Washer Fluid Should You Put In Your Car?
No matter the windshield wiper reservoir size, you should avoid topping it off to more than three-quarters full. Anti-freeze components in the fluid expand with heat and can overflow. If the liquid overflows, it could spray fluid within your engine compartment and possibly cause damage.
On the topic of washer fluid mixture, the fluid should be stored safely out of reach of children. It is brightly colored and could be mistaken for a beverage. Under no circumstances should it be consumed. Windshield washer contains poisonous substances like methanol and ethylene glycol, which are harmful if ingested.
Can You Use Water Instead of Windshield Washer Fluid?
Windshield washer fluid contains methanol and ethylene glycol, which prevents the fluid from freezing. If you replace the wiper fluid with water, you risk it freezing in extreme cold conditions. If the water freezes in the reservoir or hoses, it can cause cracks or tears.
Additionally, you won’t be able to clean your windshield effectively as no fluid will come out. If you can’t wash your windshield properly in rainy, muddy, or snowy weather, it becomes a safety risk for you and your passengers. Instead, stick to wiper fluid in freezing climates, specifically winter washer fluid.
That said, if you run out of wiper fluid while traveling and are not able to get it refilled for whatever reason, adding water to your reservoir is better than it being empty (unless the temperatures are below freezing). With an empty reservoir, attempting to spray washer fluid may cause the pump to burn out.
Does Windshield Wiper Fluid Evaporate?
Windshield washer fluid is a mixture of water and methanol, a type of alcohol. If the cap of the washer fluid reservoir is not tightly closed, the methanol will evaporate, leaving only water in the reservoir.
Another time windshield washer fluid will evaporate is when you spray it onto your windshield. In frigid weather, this can cause the alcohol-free mix (mostly water) to freeze on the windshield.
It is also wise to keep the wiper fluid container tightly sealed, whether it be in your garage, shed, or other storage area. Doing so will prevent evaporation, especially in warmer climates.
How Often Should You Check Washer Fluid Level?
As a rule of thumb, you should check your car’s windshield wiper fluid at least every two months. If you have used the wipers frequently, you should check the fluid level sooner.
When it’s time to replace your windshield wipers, you should also make it a habit of checking the wiper fluid level. By including this in your car’s maintenance regime, you can avoid dangerous situations where you can’t clean the windshield when driving.
When buying washer fluid at an auto parts store, they may even be able to fill it up for you. For example, AutoZone is known to replace your wiper blades for free if you purchase from them. They will likely refill your fluid as well if you give them your business.
The average car holds between 1 and 1.5 gallons of windshield washer fluid in its reservoir. Smaller cars might hold less and larger cars, SUVs, and pickups might hold more.
Regardless of capacity, it’s best to keep the fluid level at most three-quarters full when topping off the reservoir. This recommendation is to prevent the liquid from overflowing and damaging parts of your engine when you drive.