How do I know when my car needs a wax job?

The early days of car wax advertised some dubious claims.
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Some people may see a wax job as an extra for their car, something you do on special occasions to provide a little extra shine. But waxing your car is actually something that should be done on a regular basis. Too often car owners provide regular maintenance on the engine of their vehicle and ignore the exterior altogether, save for a few trips through the gas station car wash. The exterior of your car needs regular care as well. While neglecting the paint job may not lead to mechanical performance issues, it will result in a lower resale value, just like if you never changed your oil or got a tune up. Regular exterior maintenance will keep your car looking new for years after purchase.

And it's not just a cosmetic benefit either, regular waxing helps to protect the paint job and clear coat on your car by preserving oils in the paint that help to prevent oxidation. This is when the oxygen molecules in the air react with, and in this case burn up, the free radicals in the paint. The result is a dulled finish, and waxing can help to prevent this ugly process. Regular waxing also protects the paint from the daily wear and tear our cars get from being exposed to the outside world. Bird droppings, wind, rain, hail, tree sap, smog, ultraviolet rays from the sun -- you name it. There are a host of threats to your car's shiny finish.


As for how often you should wax your car, you'll get a different answer depending on who you ask. Wax manufacturers recommend that you apply a new coat every 45 days or so. Some newer synthetic waxes claim to provide protection for up to one year. It also depends on your preference and available time and money. If you want a showroom look all the time and have the resources, you may want to get a wax job once a month. Cars parked in a garage can go longer without a wax as those exposed to the elements.

Aside from the preference factors and recommendations, there are a couple of easy tests you can perform to know whether or not it's time to break out the cotton cloth. The age old water beading test is one. During your wash, take a close look at how the water behaves on the surface. If it beads up nicely, then your last wax job is still hanging in there. If the water doesn't bead at all and forms large "sheets" on the surface, it's time for a wax. Another quick test is performed after your car is washed and dried thoroughly. Fold a 100 percent cotton terrycloth towel until it's hand-sized and thick. Apply firm pressure to the car's surface and twist the cloth back and forth in a clockwise and counter clockwise direction. If you hear a squealing noise, then you're due for a wax job.


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  • "Auto Detailing." 2009.
  • "Car wax: Quality shine for less." April 2009.
  • "How long does a coating of wax last?" 2009. Questions&faqQuestionID=12§ion=_12#_12
  • "How Often Should a Car Be Waxed?" 2009.
  • "Waxing." 2009.
  • "What is Oxidation?" 2009.