4WD Trail Rating
The task of rating 4WD and off-road trails is never easy. It seems that every club, region, group, or organization wants to rate things a little differently. Some people prefer simple Easy-Moderate-Difficult ratings, while some prefer a 1-5 or 1-10 rating.
Even organizations that use the same numbering system (such as 1-10) - use different methods to arrive at those numbers. Trails that I (shane4x4) update, as well as many of the larger 4x4 sites use the system described by the Colorado Association of 4WD Clubs (below).
Some people, particularly newcomers to the sport, find a simple 1 - 5 rating based on vehicle type is useful. The following 1 - 5 rating system is based on several systems found on the Internet. It roughly corresponds to levels 1, 3, 5, 7, and 9 on the CA4WDC system. A rating of 0 has been added for the occasional off-highway road that has been through-paved. These are usually narrow, one-lane roads with steep grades and hairpin turns but have a tarmac surface.
- 1 Colorado Association of 4WD Clubs Rating System
- 2 Vehicle-based rating (1 - 5)
- 3 External Links
Colorado Association of 4WD Clubs Rating System
Easy Graded dirt road. Dry, or less than 3" water crossing depth. Gentle grades. 2WD under all conditions except snow. No width problems, two vehicles wide.
Dirt road. Dry, or less than 3" water crossing depth. Some ruts. Slight grades, up to 10 degrees. 2WD under most conditions. Rain or snow may make 4WD necessary. Usually one and a half to two vehicles wide.
Dirt road. Rutted, washes, or gulches. Water crossings up to 6" depth. Passable mud. Grades up to 10 degrees. Small rocks or holes. 4WD recommended but 2WD possible under good conditions and with adequate ground clearance and skill. No width problems for any normal vehicle. Vehicle passing spots frequently available if less than two vehicles wide.
Rutted and/or rocky road. No shelves but rocks to 9". Water crossings usually less than hub deep. Passable mud. Grades moderate, up to 15 degrees. Side hill moderate up to 15 degrees. 4WD under most conditions. No width problems, vehicle passing spots frequently available if less than two vehicles wide.
Rutted and/or rocky road. No shelves. Rocks up to 12" and water crossings up to 12" with possible currents. Passable mud. Moderate grades to 15 degrees. 6" holes. Side hill to 20 degrees. 4WD required. No width problems.
Quite rocky or deep ruts. Rocks to 12" and frequent. Water crossings may exceed hub depth with strong currents. Shelves to 6". Mud may require checking before proceeding. Moderate grades to 20 degrees. Sidehill may approach 30 degrees. 4WD necessary and second attempts may be required with stock vehicles. Caution may be required with wider vehicles.
Rocks frequent and large, 12" and may exceed hub height. Holes frequent or deep (12"). Shelves to 9". Mud 8" deep and may be present on uphill sections. Grades to 25 degrees and sidehill to 30 degrees. Water crossings to 18" and may have strong currents. 1-1/2 vehicles wide. 4WD required. Driver experience helpful.
Heavy rock and/or severe ruts. Rocks exceeding hub height frequent. Shelves to 12". Deep mud or uphill mud sections. Steep grades to 25 degrees and can be loose or rocky. Water crossings may exceed 30" in depth. Side hill to 30 degrees. One vehicle wide. Body damage possible. Experience needed. Vehicle Modifications helpful.
Severe rock over 15". Frequent deep holes over 15". Shelves over 15". Mud bog conditions (long, deep, no form bottom). Over 30" water crossings with strong currents. Steep grades over 30 degrees. Sidehill over 30 degrees. May not be passable by stock vehicles. Experience essential. Body damage, mechanical breakdown, rollover probable. Extreme caution required.
Severe conditions. Extreme caution recommended. Impassable by stock vehicles. Winching required. Trail building necessary. May be impassable. Impassable under anything but ideal conditions. Vehicle damage probable. Personal injury possible. Extreme caution necessary.
Vehicle-based rating (1 - 5)
The following rating system is based on several 1 - 5 rating systems. It is naturally subjective. One person's easy road is another's moderate. However, if used carefully it should give a newcomer an idea if he/she can make the trail in their vehicle. Fractional ratings indicate in-between values. For example, a road rated 2.5 should be passable with a high clearance 2WD vehicle but is more difficult than a 2.
0. Very Easy
The road is fully paved and in good condition. Most passenger cars will have no trouble at all. Such roads were typically once unpaved trails that have been paved-over with no other improvements, typically having steep grades and tight turns. A rating of 0.5 indicates that there are high berms (perhaps old erosion control berms that have been paved-over), large pot holes or other obstacles that may require higher clearance than some passenger cars.
1. Very Easy
The road is unpaved but well-maintained with an all-weather surface (such as decomposed granite, gravel or recycled tarmac). Passenger cars should have no problem unless there is unrepaired damage. A rating of 1.5 means the road may be heavily washboarded or otherwise less-well maintained but still easily passable with a 2WD low clearance vehicle.
The road is passable with a 2WD high clearance vehicle. Probably not passable with a passenger car due to deep ruts or high erosion control berms. A rating of 2.5 means the road is probably passable with 2WD but you may want to think twice without 4WD.
A high clearance 4WD vehicle is probably required but a 4WD crossover should be adequate. 3.5 is approaching the jeeps-only range. A skilled driver may make it in a 4WD crossover but you may want to leave this one to the real jeeps.
Jeeps or better only. High clearance, short wheel base, off-road tires and low range are probably required.
Custom extreme terrain vehicles only. Even jeeps won't make it.