i live in Wisconsin. the salt rusts right through the rocker panels. its rare to find a truck that doesn't have some signs of this starting mine was so bad when i bought it last year that i can put my fist through it on both sides. and its a 99 silverado. normally i wouldn't have bought a truck with rust this bad but i got the truck for 3,000 bucks (he was asking 5,600) and all of the maintenance documented from 0 miles when the truck was new. i got it from the first owner so i just couldn't pass it up.
1999 chevy silverado Z-71- 5.3, CAI intake, catback, nelson tuned, lpp lt's, vette servo, e-fans.