Off-Highway Trail Rating System
The Arizona State Association of Four Wheel Drive Clubs uses the following rating system to establish the relative difficulty of off-road trails.
Class 1
Passable by stock and two-wheel-drive vehicles; improved dirt, gravel, etc.
Class 2
Ground clearance required for stock two-wheel-drive pickups, vans, etc. Some mudholes or rocks that would stop most vehicles. Four-wheel-drive makes travel easy where others would have problems.
Class 3
Four-wheel-drive required in places, due to terrain and loose traction, for safe, easy travel. Low-range gears used occasionally. Street tires unacceptable.
Class 4
Four-wheel-drive required, usually in low range. Greatest amount of ground clearance handy due to moderate sized rocks and obstacles. Jacks and winches advised.
Class 5
Not advisable for novice drivers without experienced help. Potentially dangerous situations! Maximum ground clearance and lowest gears required. Jacks or winches indispensable when needed due to large boulders, steep inclines, etc.