Ratings are part and parcel of all sports from golf to rock climbing to river running and definitely to four-wheeling. There are lots of systems for rating roads and trails. In Arizona the standard appears to be set by the Zuks of Arizona (ZOA) Club. It is a Class 1-4 system. Zukiworld has a Class 1-10 system designed for the Moab area but useless everywhere. Since we are 30+ year river runners, we prefer a Class 1-6 system. No one else uses a Class 1-6 except us. Below are all three systems. We list our own rating system last. For the purposes of this blog, we will use all three systems with ZOA's first; Zukiworld's second and ours last. Here is how the notation will be used in the blog
ZOA: 1; ZW: 2; JS: 1
Here are the ZOA Trail Ratings:
Ratings depend on a lot of variables, especially the type of vehicle and the modifications that have been done to it. One trail that would be difficult for a stock 4x4 might be easy for a modified one. Everyone has their own trail rating system, but I like the one from the Fun Treks books by Charles A. Wells. It's simple and easy to use. Think of a stock Samurai when reading the descriptions.
The only thing added is the EXTREME rating, because that's where the rock buggies come in to play. And that's a whole different ballgame.
#1- EASY TRAILS
Gravel, dirt, clay, sand, or mildly rocky road. Gentle grades. Water levels low except during periods of heavy runoff. Full-width single lane or wider with adequate room to pass most of the time. Where shelf conditions exist, road is wide and well maintained with minor sideways tilt. Four-wheel drive recommended on most trails but some are suitable for two-wheel drive under dry conditions. Clay surface roads, when wet, can significantly increase difficulty. #2-MODERATE TRAILS
Rutted dirt or rocky road suitable for most sport utility vehicles. Careful tire placement often necessary. Four-wheel drive, low range, and high ground clearance required. Standard factory skid plates and tow hooks recommended on many trails. Undercarriage may scrape occasionally. Some grades fairly steep but manageable if dry. Soft sand possible. Sideways tilt requires caution. Narrow shelf roads possible. Backing may be necessary to pass. Water depths passable for stock high-clearance vehicles except during periods of heavy runoff. Mud holes may be present especially in the spring. Rock-stacking may be necessary in some cases. Brush may touch vehicle. #3-DIFFICULT TRAILS
Some trails are suitable for more aggressive stock vehicles but most trails require vehicle modification. Lifts, differential lockers, aggressive articulation, and/or winches recommended in many cases. Skid plates and tow hooks required. Body damage possible. Grades can be steep with severe ground undulation. Sideways tilt can be extreme. Deep water crossings possible. Shelf roads extremely narrow; use caution in full-size vehicle. Read trail description carefully. Passing may be difficult with backing required for long distances. Brush may scratch sides of vehicle. #4- EXTREME TRAIL
Lift, lockers, aggressive articulation, large tires and winches REQUIRED. Body damage imminent. Breakage common. This is the mega crawler's playground, AKA the Rock Buggies. Do not attempt if you are not an experienced rock crawler. Click here for the source of these ZOA ratings. Note that the link probably won't work as it directs to a "Members Only" forum. If you are a ZOA Member, the ratings can be found in the "Trail Talk" section at the bottom.
-------------------------------------------------------------------------------------
Here are the Guidelines for the ZukiWorld difficulty ratings:
The following ratings are for Moab area roads in dry conditions. The effect of snow or rain varies greatly depending upon the altitude of the roads and the type of soil the bed consists of. Driver Beware!
1: County dirt road maintained for high clearance 2WD and 4WD use in adverse conditions.
2: County dirt road with infrequent or light maintenance after rain or snow, 2WD high clearance with low gears, otherwise light duty 4WD.
3: Road with frequent use, but seldom maintained. Dirt, sand and slick rock surfaces, with mud holes possible (note: maybe impassable when wet due to soil composition.). 4WD recommended under most circumstances due to ruts or wash erosion.
4: Road surface consisting of loose rock, dirt, and sand with some slickrock surfaces. Erosion, washes, gulches and rock steps no higher than 12". 4WD is recommended with good ground clearance and driving skills. Aggressive tires and limited slip would be a plus. Water and mud is possible.
5: Road surfaces are rutted, rocky and sandy with steps not exceeding 14", with considerable slickrock surfaces. Water not exceeding 12" with some mud possible. Good vehicle approach and departure angles are helpful. Tall tires (33" plus) and traction added device (lockers, limited slips) is recommended. Above average driving skills are desirable.
6: Roads are difficult with considerable erosion damage repaired just enough to be passable. Water in excess of 12" is possible with mud conditions. Steps not exceeding 24". Tall tires (33" plus) with traction added devices (lockers, limited slips) are recommended. A winch would be a plus. Enhanced suspension travel and ground clearance are helpful. Excellent driving skills are recommended.
7: Trail consists of rock; sand and considerable slickrock with many steps exceeding 24". Steep inclines and declines are prevalent. Enhanced off road equipment is required including locking devices (front & rear), tall tires, maximum vehicle ground clearance, and tow hooks. A winch is desirable. Excellent driving skills are required. Vehicle mechanical or body damage is likely. Roll over possibilities exist.
8: Extreme trail similar to #7 except a bit more extreme. Excellent driving skills are required. Vehicle damage is likely. Equipment or mechanical damage is probable. Lockers front and rear, as well as a winch are mandatory equipment!
9: Extreme and beyond, similar to #8. Vehicle damage is likely. Excellent driving skills are required. Roll over is very common. Winches, spare parts and tools are recommended. Be prepared to spend the night on the trail. Beyond the capability of most modified stock vehicles.
10: Let the carnage begin! Buggy territory. Street driven 4X4’s should not attempt this trail. Modified factory vehicles will not be able to complete this trail.
Click here for the source of the ZukiWorld ratings system.
-------------------------------------------------------------------------
Here is our own Class 1-6 rating system adapted from the official "International Scale of River Difficulty."
Class One: Suitable for all vehicles, even low clearance rental sedans. Most normal Forest Roads fall into this category.
Class Two: Suitable for Novices. 4WD seldom used. Few obstructions all easily avoided. Generally high clearance.
Class Three: Intermediate Skills & equipment required. Frequent 4WD may be required. Numerous obstructions. Some scouting may be advisable. Class III would be the maximum upper limit for a stock Samurai and is generally not advised for novice drivers.
Class Four: Advanced. Class IV routes are not suitable for stock vehicles. Clearance, suspension, gearing and other vital modifications are required to navigate these routes. Best navigated with other experienced drivers. Advisable to carry a full range of recovery tools and overnight supplies in case of major breakdown.
Class Five: Expert. Only highly modified vehicles driven by experts are capable of navigating Class V routes. Examples would be well known boulder and ledge problems. Most Class V routes are nationally recognized and named and have accumulated much legend and renown.
Class Six: Almost impossible to navigate. Suitable only for teams of experts with vast experience and highly specialized equipment. High likelihood of injury to vehicle and/driver. Navigation of Class VI routes usually brings national notoriety to the vehicle and driver.
Click here for the American Whitewater Association's Safety Code. Scroll down to the end for the description of the Class I-VI system.
