I wait for a warm day (anything over 34) and I hand wash it. A car wash is going to grind the road salt/sand/dirt into your paint and scratch it. If you are talking about the self car wash, different story, that's a good idea. I also make sure my car goes into the winter with a lot of wax on it and every chance I get during the winter months its in the garage getting another coat. I probably wax my car more than some people wash theirs.

Pat