If you are testing yourself and your equipment to learn your ability or to improve your ability, be prepared to admit defeat. Destroying your equipment and the route in the process to say you have driven a road or trail helps defeat those who are trying to keep these routes open for continued use. You can always return to an un-abused trail or road to try again. A road or trail's rating comes from the worst spot that must be traversed. If you drive a stock vehicle, normal open differentials, tires smaller than 30 inches, or if you are an inexperienced Four Wheeler, add 1 to the number rating.
Weather is important in a route's rating and can change it quickly.
A normally dry section of road rated 5 can change to an 8 if it is turned to mud from a weeks worth of rain, or spring run-off, or if there is more than 6 inches of snow. These book can be purchased from the Association. They describe many of the 4WD roads in the National Forest and on BLM land. Dry, or less than 3 inches water crossing depth. 2WD under all conditions except snow.