Can Windshield Washer Fluid Be Stored in the Trunk During Summer?
3 Answers
You can store windshield washer fluid in your car, but using fluid that has been exposed to intense sunlight poses safety risks. Here’s the relevant information: Windshield Washer Fluid: High-quality washer fluid mainly consists of water, ethylene glycol, alcohol, corrosion inhibitors, and various surfactants. The alcohol and ethylene glycol can evaporate under high temperatures, causing the fluid to deteriorate. This shows that windshield washer fluid is not heat-resistant and should not be exposed to direct sunlight, so it is not recommended to store it in a hot car. Using Deteriorated Washer Fluid: Exposure to sunlight can cause the fluid to degrade. If used, deteriorated fluid can corrode the wiper blades, fail to clean the windshield properly, impair the driver’s visibility, and compromise driving safety. Additionally, degraded fluid loses its concentration and may no longer meet the requirements for antifreeze washer fluid.
It's actually quite common to keep windshield washer fluid in the trunk during summer. My car always has two or three bottles stored year-round. The main components of windshield washer fluid are water and cleaning agents. High temperatures in the trunk might cause some water evaporation, slightly reducing its effectiveness but won't make it spoil. However, be careful not to buy those ultra-cheap off-brand products with poor-quality plastic bottles that can easily deform or leak under high temperatures. I once encountered a bottle that ballooned like a balloon—fortunately, it didn't burst. I recommend choosing products from reputable brands. There's no need to use the antifreeze type in summer; the regular cleaning type will do. Make sure to tighten the cap securely and avoid storing it near lighters or similar items for safety. Placing a cardboard box in the trunk can provide some insulation, significantly extending the lifespan of the windshield washer fluid.
When it comes to storing windshield washer fluid in the trunk during summer, my experience suggests it depends on the situation. In our southern regions where temperatures often hit 40°C, the trunk can reach 60-70°C after prolonged exposure to sunlight. Regular windshield washer fluid can indeed be stored, but don't stockpile too much—two or three bottles at most. Once I bought a batch on sale, only to find it turned yellow and clumped up after half a month in the trunk. Later, I switched to the blue-bottled type, which has better light resistance. As for winter antifreeze washer fluid, it's best not to store it in summer as the methanol content can easily evaporate in high heat. I've designated a corner in my trunk specifically for washer fluid, keeping it away from metal parts like the spare tire and tool kit. If you frequently take long trips, buying as needed is the most reliable approach—grabbing some at gas stations saves you the hassle of carrying it around.
