and end up in Carson City, Nevada. My questions is that it doesn't seem to have access to the Devils Canyon/Sequoia Parks? Is there something missing on my map/routing software or do I have to take the Western route 99, which doesn't look to be as good a road, and is a bit out of our way, to get to them?
When going north on US 395 when you arrive at Minden/Gardnerville take SR 88 over the Sierras and that will get you into the Stockton area. From there it is fairly easy to access Yosemite and Sequoia and, of course, San Francisco, the Pacific Ocean and the Giant Redwoods. You can take a few short miles detour and visit Lake Tahoe off SR 88 as well. The great American author Mark Twain in his book
Roughing It called Lake Tahoe 'the fairest picture the whole earth affords, it's air is the air the angels breathe'. It is worth a visit. There are other passes over the Sierras south of SR 88 but SR 4 Ebbetts is not all that RV trailer friendly and is narrow in places and so is the top section of SR 108 Sonora Pass. SR 88 is a very RV friendly route as is US 50 and IR 80.