During the winter months, many roads are covered in salt, and salt damage is rough on vehicles. Salt sticks to surfaces, seeps into cracks, and speeds up rust, especially on the undercarriage. If left too long, it'll weaken metal parts and create the perfect environment for rust. Washing your vehicle regularly during winter—especially after driving on wet, salty roads—prevents damage.

Rinse Off the Salt Before It Sticks

Before scrubbing, spray down your entire car with fresh water to rinse any accumulation of salt. A garden hose works fine, but a pressure washer or self-service car wash is better for reaching tough spots. Focus on these areas:

  • Wheel wells and tires – Salt remnants collect here and can lead to rusted brake components.
  • Undercarriage – An underbody spray with extra attention to the metal frame and exhaust system can help prevent corrosion.
  • Bumpers and lower panels – These areas catch the most slush and road spray. You can usually see a visible film of road salt on the surfaces.

“Road salt is essential for safe winter driving, but can wreak havoc on your car’s finish and undercarriage, especially if it lingers for too long,” says Morgan Lucas, CEO of Lucas Oil. “Salt buildup can cause corrosion, rust and long-term damage if left unchecked. That’s why it’s critical to wash your car regularly in the winter – especially after driving in snowy or slushy conditions.”

If you can't commit to regular rinsing, get into the habit of knocking snow buildup off the car when you park in your driveway or garage.

Snow falls off a car to melt in a garage.
Snow with rock salt from roads causes garage floors to deteriorate. Credit: Emily Fazio

Use the Right Soap and Tools

Not all car soapy water can remove salt accumulation effectively; some soaps are too mild to break down the residue.

Choose a soap made for winter grime, preferably one with salt-dissolving ingredients. A soft microfiber wash mitt or sponge is best to avoid scratching the paint when using salt removers. Work from the top down, washing one section at a time and rinsing often. Pay extra attention to areas with extra buildup of salt, like around doors, wheel wells, and the trunk.

For the undercarriage, use a long-handled brush or high-pressure hose. A pressure washer works well too, but use a wider angled nozzle to prevent damage. Even using a garden sprinkler under the car can help flush out caked salt from hard-to-reach areas.

Add a Protective Coating After Washing

Once your car is clean, a can extra layer of protection can keep salt from sticking as easily next time.

A high-quality wax adds a barrier against salt and moisture. “Using products specifically formulated to break down salt and protect your vehicle’s paint, like our Lucas Oil Slick Mist Speed Wax and Ceramic Speed Wax, helps create a shield against corrosion and keeps your car looking – and performing – its best, season after season,” says Lucas.

For added protection:

  • Apply wax every few weeks during winter, especially after washing away loose salt.
  • Use a ceramic coating for longer-lasting defense against salt and road grime.
  • Spray a rust prevention coating on the undercarriage to prevent corrosion and reduce the likelihood of rust forming.
  • Keep floor mats clean—salt and moisture from shoes can damage the interior.

FAQ

How often should I wash my car in the winter?

Wash it at least once every two weeks during winter. More often if you drive in harsh road conditions. If you notice white salt buildup on the body or undercarriage, it’s time for a wash.

Is it bad to wash my car when it’s freezing outside?

No, but avoid washing if temperatures are below 20°F, as water can freeze in door locks and seals. If needed, use warm water (not hot), and dry your car well, especially around doors and windows, to prevent ice buildup.