If there is a substantial bear issue, I'd press
the local yokels that run the place to install
those metal bear boxes/containers that you see in
campgrounds throughout Yosemite.

Spent about 10 days up in Tuolumne this past summer
the bears were much less of an issue compared to
the summer of 92/93? when we were there..

http://timschneider.org/goob_goes_yos/ggy.html

(search down the page for the word 'bear' if you
 dont want to read the entire long boring story)

that year, they were can-opening cars left and
right (think it was drier that year in the mtns?)

they were pretty much absent this year.. needless
to say, I'd think they'd be able to rip
open a vanagon door in pretty short order, I wouldnt
take any chances personally, our vehicles are precious
enough to us as is

cheers,

 -tim

90 syncro westy
mesa, az