A clean windshield is a vital part of safe driving. Smears, dirt, dust, and other debris can significantly reduce or distort your vision, particularly in poor driving conditions. However, traditional windshield cleaners contain methanol. Even in small amounts this chemical can be dangerous and have detrimental effects on health and the environment. Given this, many drivers are looking into safer and potentially cheaper alternatives. While other store-bought options are not always as effective or less polluting, the good news is that it is relatively simple to make your own windshield washer fluid at home.
All you need to achieve this is a little time and access to a range of household ingredients that you will most likely find are already in your kitchen, garage, or shed. Here we explore four different options for making homemade windshield washer fluid.
Option 1: Window Cleaner
Diluted window cleaner makes an ideal general purpose windshield wash. However, to be effective it is important to choose a window cleaner that doesn’t leave any residue or suds behind. It is also preferable to use distilled rather than tap water to prevent a build-up of mineral deposits in the pump and spray nozzles of your vehicle windshield washer system. To create homemade windshield washer fluid with window cleaner, follow the steps below:
- Find a clean empty container that can hold at least one and a half gallons. Ideally, you also want one that is easy to pour from.
- Add a gallon of distilled water to the container.
- Add one cup of glass cleaner.
- Mix well.
- Use a small amount of the solution on a clean rag to test it on your windshield. If the solution wipes away dirt without leaving any residue, then add it to your car’s windshield washer reservoir.
Option 2: Ammonia and Dish Soap
This option is great if you are likely to be driving through very muddy terrain. However, care needs to be taken, especially with the ammonia. Work in a well-ventilated area and use ammonia that is free from surfactants and additives. You also want to ensure that the ammonia will not cause suds. Similarly, make sure the dish soap you use is suitable for glass and does not foam too much. As with the previous option, use distilled water to maintain the health of your pump and spray nozzle. To create homemade windshield washer fluid using ammonia and dish soap, follow the steps below:
- Find a clean, empty container that can hold over a gallon. Ideally, choose one that is easy to pour from and that has a lid for easy mixing and storage.
- Add a gallon of distilled water to the container.
- Add one tablespoon of dish soap to the water. Measure this carefully, if you use too much the mixture will be too thick.
- Carefully add half a cup of ammonia to the container.
- Mix the contents together. The best way to do this is to put the lid on the container and shake it vigorously.
- Test on a small area before adding to your car.
Option 3: Vinegar
Vinegar is well known for its cleaning properties and is often used as an alternative to household window cleaner. The same properties make it ideal as a homemade windshield cleaner. It is important to only use white vinegar so that you don’t stain your clothes or leave behind a residue. Vinegar is not recommended in warmer climates or during warmer summer months because the smell can become very unpleasant. To use vinegar to make homemade windshield cleaning fluid, follow the steps below:
- Find a clean, empty jug with just over a gallon capacity.
- Add ¾ gallon of distilled water.
- Add four cups of white vinegar.
- Mix well, ideally by shaking.
- Check on a small area before adding to your car.
One additional point to note is that if the temperature in your area is close to freezing, do a freeze test before you add the solution to your vehicle. Leave a cup of the vinegar and water solution outside overnight. Check it in the morning, if it has frozen, add two further cups of vinegar to the main solution container and try again. If the new strength solution is frozen the next morning, then you may want to try our final option.
Option 4: Rubbing Alcohol
This isn’t so much an additional cleaner as it is an addition you can make to any of the previous three options. Rubbing alcohol or isopropyl alcohol can be added to any of the previous cleaning methods to prevent the mixtures from freezing. We recommend that in mild winter conditions, you use 70% rubbing alcohol. However, in extreme cold 99% rubbing alcohol is more likely to be effective. To add rubbing alcohol to your homemade windshield cleaner, just follow the steps below:
- Make your preferred cleaning solution.
- Add one cup of rubbing alcohol to the mixture.
- Leave a small amount outside overnight.
- In the mixture freezes, add a further cup of rubbing alcohol to the main container.
- Repeat test.
Safety Hints and Tips for Homemade Windshield Cleaning Fluid
Preventing your homemade windshield cleaning fluid from freezing is vital to the health of your vehicle. If the windshield washer fluid freezes it can rupture the hose, leaving you with a potentially costly repair.
It is also important to ensure your windshield cleaner fluid reservoir is drained before changing to a different type of mixture. As well as emptying the reservoir it is a good idea to flush the lines with clean water to prevent potential clogs. If you are using the same type of cleaner again, however, then it is safe to simply top up the fluid that is already there. It is a good idea to use a funnel to add fluid to the reservoir to prevent spillages. Although the vinegar, ammonia, and rubbing alcohol used in the mixtures are extremely diluted, they could still damage paintwork and other surfaces over time.
Make sure you store your windshield cleaning fluid mixtures safely. Label the containers clearly with permanent marker and keep out of reach of children and pets. You should also ensure that they are stored in an area where they are exposed to consistent temperatures. As well as stopping them from freezing, this prevents them from expanding/contracting in their containers and causing potential spills and other accidents.
Plain water can be used as a substitute for any of these mixtures, but only in an emergency. Water alone will not cut through grime effectively, is likely to smear, and serves as a breeding ground for a host of different bacteria.
Finally, if your car’s sensors are having difficulty measuring the amount of washer fluid in the reservoir, add a small amount of blue food coloring to your mixture. This should stop the sensor from seeing through the fluid and misreading the reservoir levels.