Why cars rust

the new spray on ice preventer is more corrisive than salt.

Here in Indiana they use it long before it snows, once it gets wet that crap is all over the car. The combonation of cheap recycled steel and the salt it is going to rust.

I had an oil filter rust out on my old plow truck after one season of plowing and letting the truck sit all summer. Let's see, it was filled with OIL

The only way to have a rust free car would be to have it in a climate controled room, never get wet, every single metal piece painted when it was clean, dry & rustfree.

My 81 Imperial is rust free on the surface, but I had it on the lift and my mom ask why her car had rust on it. The driveshaft and other steel parts that are not painted had rust on them. 15,000 miles, stored winters (never driven in snow) driven in the rain 4 times in the 1st 7 years. Has been washed maybe 3 or 4 times since 1993.

There is drains in the panels for water to run thru. they get clogged up with junk and that causes rust.

the comment about keeping one clean and doing proper maintenance is correct to a point. But if you drive a car on salted roads there are places you cannot get to and that is where it will start to rust.