Will a Car Wash Hurt Your Car’s Finish?

It'll clean your car, but at what cost?

Will taking your car through an automatic car wash damage the finish? Sadly, the answer is yes. While some types of car washes are worse than others, any time you wash your car—even if you are carefully hand-washing it—you are essentially applying abrasive and/or harsh chemicals to the paint finish and the risk of swirls and scratches in the finish is always there. That’s the bad news. You can minimize the degradation of your paint’s appearance. Plus, most modern car finishes applied at the factory include a topcoating that is very durable and should hold up for at least ten years.

Tunnel car washes with rotating brushes

The “traditional” old-style car wash with rotating bristle brushes is much maligned in favor of other, newer car wash technologies that are described as gentler to your car’s finish. But head-to-head comparisons have shown that the old-school car washes will actually cause less damage to your car’s finish than the newer alternatives because the brushes do not hold onto abrasives (like grit) to the extent that soft cloth scrubbers do.

Soft-cloth car washes

Some car washes that are not “touchless” feature flaps of cloth that massage your car clean and seem less aggressive. But they do retain the abrasives from every car that has preceded yours, more than brushes do. And, latent abrasives in the scrubbers are the primary offenders when it comes to car finish damage.

Touchless car washes

Car washes that use the “laser wash” approach do not have the abrasive effect on your paint finish that car washes making direct contact with the vehicle do. But there is a trade-off. They do not get your car as clean, as a little scrubbing is necessary to dislodge some of the grit and grime. And, they use more caustic detergents to compensate for the lack of direct contact. A touchless car wash is okay once in a while, but regular exposure to these chemicals will degrade the finish.

Washing by hand

Most auto detailers who pursue the perfect car finish insist that only hand-washing will get you there. But even with hand-washing there are risks. Using the same sponge to clean the vehicle’s painted surfaces and the tires and wheel wells is a common mistake that introduces abrasives into the cleaning process. Take care to segregate your sponges, and rinse and clean them, as well as your microfiber towels, religiously. When washing the inside of your car, there’s only one type of polish that you should be using—and it’s already in your pantry.

Here are a few tips for safe and effective automatic car wash use:

  • If you are waiting in line at a car wash and the vehicle in front of you looks like it is fresh from a week of off-roading in the mud, give up your place in line and come back another time. Car washes of all types “self-clean,” but not that fast. It takes a few cycles of rinsing to rid the brushes or soft cloth of excessive grit that can damage your finish.
  • Evaluate the facility. If it’s clean and modern on the outside, chances are good that they take care of the washing parts, too. You should never take your car through a dirty car wash—or do these 10 horrible things to your car.
  • Most of the “extras” are probably not worth paying for. A spray-on “wax” will give a nice sheen but will fade in a few days and is essentially a waste of money—just like these seven ways that you’re wasting money on your car. Do select the undercarriage cleaning, but only a couple of times a year.

The Family Handyman
Originally Published on The Family Handyman