How Often Should You Wash Your Car In The Winter?

Winter brings many welcome things, like the season's first snowfall, hot chocolate, or an excuse to use your car's heated seats. Yet, precipitation and freezing temperatures are also accompanied by road salt, a necessity to minimize slipperiness. Depending on where you live, these treatments may be used occasionally or routinely. There are also different formulations, such as sodium chloride, calcium chloride, and magnesium chloride, which vary in cost and effectiveness. However, they all have one thing in common: the ability to accelerate the development of rust (oxidation) on metal. Sodium on French fries is good, sodium on your car, not so much.

Short of staying home, there's no way to prevent your car from coming in contact with road salt. The next best thing is keeping it clean. This isn't to maintain a shiny exterior, which is almost impossible on wet or slushy roads, but to prevent the buildup of residue that can start to eat away at the body panels and undercarriage. Cleaning frequency depends on the level of brine exposure. At minimum, wash once a month, and wash more frequently if you regularly drive your car on salted roads. There are also unbreakable winter driving rules to consider.

There's no hard-and-fast rule about cleaning away winter grime. And, yes, you can wash your car too often. However, the answer really depends on how frequently your vehicle is exposed to road salt. In regions where snow- and ice-covered roads aren't the norm, a monthly visit to the car wash or a visit after large storms will suffice. 

The challenge is determining an effective car-washing practice if you live in an area where snow and ice are more common. In other words, contact with road salt is practically an everyday occurrence. Here, you'll want to get into more of a routine than a post-storm response with weekly or biweekly washings. Adding to the complexity of Northern climates and keeping your car clean is the temperature. Washing your vehicle at home isn't very practical if the thermometer seldom rises above freezing — the water just makes the driveway even more slippery.

The most convenient way to keep your car clean in the cold is by visiting a car wash. Ideally, choose a touchless facility without brushes that grind salt and dirt into the paint. You'll also want a place that has an undercarriage wash to access the suspension, exhaust system, and brakes. A standard surface wash won't clean these hard-to-reach components. Going through a commercial car wash also often means warm water, which helps break down the grime, and there's less to worry about when it comes to developing ice that can damage door seals.

If you take the DIY approach, wash your car when it's at least 50 degrees Fahrenheit outside and, ideally, in the afternoon (the warmest part of the day). It's more comfortable, and the residual water is more likely to evaporate than freeze. Cleaning underneath the car can be more challenging, but an undercarriage washer (think a lawn sprinkler on wheels) connects to the hose to make the job easier. Jalopnik discovered this undercarriage spray hack if you don't feel like spending $25 to $50 on another contraption. Of course, use the proper supplies and materials to clean the topside: car wash mitts and soap, not old towels and dishwashing liquid. Dry with a microfiber cloth.