Call them the "big three" of winter hazards. Road de-icers, precipitation and environmental crud such as bird droppings, road grime and tree sap can all destroy a vehicle's paint and finish.
Keeping your car clean is especially important in the winter months. The International Carwash Association recommends washing your vehicle at least once or twice a month in the winter.
The most damaging to your car's shiny finish: salt and other road de-icers. Even the toughest paints and finishes can be compromised by the corrosive mixture of salt and sand used on icy roads. Sodium magnesium, used instead of sodium chloride in some locations, can be corrosive and can cause rust on a vehicle's undercarriage.
Environmental substances such as tree sap can also harm a car's finish and even rain and the pollution it carries can cause permanent damage.
If you wash your own car, Consumer Reports advises using dedicated car-wash products instead of household cleaning agents, which can strip off a car's protective wax.
And whether you take your car to an automatic carwash or wash it at home, Consumer Reports suggests drying it with soft towels. Letting it air dry can result in watermarks, which are hard to remove.