I drive my CRV on Pennsylvania state forest roads year round and have
had no problems. These roads are unpaved and not maintained very well
during the winter (plowing) and I have not had a problem. They are also
very muddy in the spring.

I do take it easy though, no real rough stuff and such, but there are
many grades that I climb and descend. I also run M&S tires that have a
slightly aggressive tread pattern. One reason for buying my CRV was for
running these roads as they are a wonderful place to view wildlife and
there are many primitive camping spots and trout streams along them.

Here's 2 pics from my travels.

http://tinypic.com/i35tn7.jpg

http://tinypic.com/i35tv7.jpg

Here's a pic of my wifes van when I used it on a forest road last
summer. She was not happy.

http://tinypic.com/i35u9i.jpg