Vinegar has become one of the most popular home remedies among drivers. It is inexpensive, easy to get, and, according to those who recommend it, it serves several functions on the car glass.
Cleaning and degreasing the glass
The most recommended for this task is distilled white vinegar, since it leaves the least residue on the surface. Its main component is acetic acid, to which disinfecting and degreasing properties are attributed, capable of leaving the glass clear.
For this reason, it is used to remove insect remains, bird droppings, tree sap and hard water stains, which usually have a high mineral content. It is also mentioned that, in cold or humid climates, it can help reduce condensation inside the vehicle.
To apply it, it is recommended to dilute it in equal parts with water and use a microfiber cloth to avoid scratches, since pure vinegar in excess could damage rubber, plastics, or paint on the car with frequent use.
The belief about frost and ice
The other most widespread use is as a home method to delay the formation of frost or ice on cold mornings. The explanation that circulates is that the acetic acid in vinegar lowers the freezing point of water, which would make it harder for ice to form or stick to the glass.
This is a chemical principle: mixing a solute with water can lower its freezing point, something similar to what happens with salt.
However, there are no studies or concrete, verifiable data that confirm how much that freezing point is reduced when diluted vinegar is used, or how effective it is against severe frosts.
For this reason, this use remains more of a popular belief among drivers than a solution with proven scientific support.
Along with this trick, other home remedies are often mentioned with the same level of anecdotal support, such as rubbing the glass with raw onion or with a cut potato, although these also lack verifiable evidence to support them.