How to Wash a Car Step by Step: Two-Bucket Method, Soap, Drying and Glass

One bucket holds the shampoo solution; the other holds plain water. Load the mitt in the soap bucket, wash one panel, then scrub the mitt against the grit guard in the rinse bucket before it goes back for more soap. The dirt the mitt picked up settles in the rinse bucket instead of going back into the soap, so each panel gets a cleaner mitt than it would from one bucket.

A third bucket for the wheels keeps brake dust out of both. Change the rinse water when it turns cloudy. The method lowers the risk of wash scratches; it doesn't remove ones that are already there (how to remove swirl marks).

Wheels get their own bucket, brush and mitt, and they wait until they have cooled. Specialized wheel cleaners go first: Mothers advises cleaning wheels "before washing the entire car", with a wheel-only mitt "so you don't traffic brake dust and other nasty ground-level substances with the rest of your car" (Mothers). On a bucket-only wash with plain soap they can go last, as in the steps above, as long as they never share the paint mitt. Rotiform, a wheel maker: "Never clean wheels when they are hot" (Rotiform).

1. Rinse the wheel, the tire and the wheel well. Hyundai's manual says to "Thoroughly flush the vehicle underbody and wheel openings with lukewarm or cold water once a month, after off-road driving and at the end of each winter" (Hyundai).
2. Wash with the cleaner the finish allows (table below): a soft brush for the barrel and spokes, the wheel mitt for the face.
3. Brake dust that soap leaves: an iron remover. CarPro says its IronX works to "dissolve the sintered iron by forming a water soluble iron complex" and turns purple or red as it works; it is pH neutral, rules out anodized surfaces and unknown aftermarket finishes, and must not dry on the wheel in direct sun (CarPro). Skip acid cleaners: Mercedes-Benz says acidic wheel cleaners used on brake dust "could damage wheel bolts and brake components" (Mercedes-Benz).
4. Scrub the tire sidewall with soap and water, which is what Consumer Reports names for tires (CR), then rinse and dry the wheel.
5. Tire dressing last, on a dry tire, on the sidewall only. One maker's directions: "Surface must be 100% dry"; spread it "evenly across tire sidewall surface and wipe off any excess", and let it dry, "Preferably 1 ~ 2 hours", before the car is driven (CarPro).

LA tap water is hard. LADWP's 2022 averages are 8.6, 9.8 and 16.3 grains per gallon across its zones, where more than 7 counts as hard, and LADWP lists "fewer water spots on air-dried dishes and automobile finishes" among the benefits of softened water. Left to air-dry, those minerals stay on the paint as spots (LADWP).

• Dry straight away, roof and glass first, then down the sides.
• Blot or lay the towel flat and draw it toward you, without pressure; Consumer Reports suggests blotting rather than dragging (CR).
• Use plenty of plush microfiber, and swap to a dry towel when one stops absorbing.
• A blower clears water from mirrors, badges, grilles and wheels that would otherwise drip later. XPEL names "an electric blower or plush microfiber drying towel" for its color film (XPEL).

Spots that stay after a wipe with clean water have started to etch: see how to remove water spots from car paint or water spot removal.

Streaks come from residue: cleaner drying before you wipe it off, a towel that is dirty or treated with softener, or the film that builds up on the inside of the windshield. So:

• Work on cool glass in the shade, one window at a time.
• Use two towels: one damp with cleaner to clean, one dry to buff.
• Inside, spray the towel, not the glass. That's AAA's tip (AAA), and it keeps overspray off the dash.
• Wipe across outside and up and down inside, so you can tell which side a leftover streak is on.

Tinted windows: film makers disagree on cleaners, so follow your film's own care card. 3M allows "standard pH neutral glass cleaners" without abrasives and asks you not to clean the windows for 48 hours after installation (3M). XPEL allows "mild, non-ammonia glass cleaners" on its PRIME film (XPEL). LLumar says to use "your favorite household cleaner" (LLumar). If you don't know the film, a non-ammonia, non-abrasive cleaner is the cautious choice.

Yes, but a deep-pile microfiber mitt is the better tool. It holds more solution and lets grit sink into the pile; a flat cloth holds little and pushes what it picks up across the paint. If you use cloths, use several, fold them into quarters and turn to a clean face often.

Look after them, or they stop working (The Rag Company):

• No fabric softener or dryer sheets: softener "coats and clogs the fibers so they stop absorbing and start smearing".
• No hot water or high-heat drying: heat is what damages microfiber.
• Wash wheel and interior towels apart from paint, glass and drying towels.
• A towel or mitt that touches the ground goes to the wheels from then on, never back to the paint.

Dark colors show the most, because dust, pollen, water spots and fine scratches are all lighter than the paint. Silver, gray and white hide light dust and fine scratches better; white shows road tar and dark grime instead.

Dark paint also gets hotter. Berkeley Lab researchers measured the roof of a silver car up to 45°F cooler than the roof of a black car, both parked in the sun in Sacramento (LBNL). On hot paint, shampoo and water dry before you reach them, which is where the spots come from.

• Wash early or late, and in the shade even more strictly than on a light car.
• Rinse and dry one section at a time instead of soaping the whole car.
• More mitts and towels, changed sooner, and a blower, so fewer passes touch the paint.
• Check in daylight from an angle: swirls on dark paint show in direct light. Some fine scratches can only be polished out (swirl marks).

A clean, dry car is the moment to add protection. Hyundai says to "wax the vehicle when water will no longer bead on the paint" (Hyundai), and Consumer Reports suggests wax at least once a season (CR). A spray sealant is the quick option; a ceramic coating is a professional job (wax or ceramic coating; car wax and sealant).

Between washes, take bird droppings off as soon as you see them: Hyundai warns they "may damage painted surfaces in just a few hours". How often to wash in LA sun, dust and rain: how often should you wash your car.