Any of the 'wilderness' areas are off limits to vehicles and anything mechanized so that's where I'd start my searching. Nat'l forests next. Most are full of hiking trails w/maps available many places.
Just curious, if you're seeing all these vehicles and watching folks bugling from their trucks, it doesn't sound like you're too far from the road either.
Most days I couldn't tell ya who or what went down the rd. I'm in the woods most of the day. The rigs I do see in the middle of the day from camp I could care less about since most are just visiting or checking out new areas in their off time.