If you use dish soap to wash your car it'll take the wax off in just a few washes. I like to use turtlewashnwax or whatever it's called,so I only have to wax twice a year.But then again we don't get winters like you guys,when I lived in Calgary 20 years ago I can remember pulling inside a diy car wash (at -20C)washing my car,drying and then pulling out of there and getting stuck inside my car because the door froze to the weatherstripping
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