Have a 2005 GMC 3500 EB SMB permanent raised roof with about 99,000 miles and with Quigley 4x4. Planning to spend a few or so weeks perking up the west coast in April from southern CA to Seattle. Enjoy spending some time driving primitive roads, hopefully with some interesting stops or views, that might require 4x4 (H or L) but with such a big rig not a real rugged road or a true off-road. (Besides, we are over ¾ century old.) Suggestions?
There are lots of Forest Service roads in the Rouge River/Siskiyou and Siuslaw National Forests in Oregon. If you want to do some dune driving then stop in Florence, OR and visit the Oregon Dunes National Recreation Area.
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Larrie
Read detailed trip reports, see photos and videos on my travel blog, luinil.com.
Current van: 2002 Ford E350 extended body camper with Colorado Camper Van pop top and Agile Offroad 4WD conversion.
For Washington, buy a Discover Pass ahead of time. They're cheap, and allow free camping on state Department of Natural Resources (DNR) land, and free day use at state parks, but can be hard to find a vendor when you need one. DNR land includes some surprisingly good developed campsites not far from the overcrowded/unavailable Olympic National Park campgrounds, if you're going that way, and if you aren't put off by logging activity.