I have a '91 Navajo that I have run all year round in Wisconsin. Also had 10 mile commute on "salt road" I've seen them salting bare, dry pavement in winter before it snows. Anyway, rust wise it was great till about '99 or '00. Driver side rocker now gone (like every explorer over 5 years old), driver door going.
10 years b4 rust catches up in WIS = not too darn bad!
Wish I could say that about the trannie