Lesson 1/ Learning Event 1
In combat situations, wheeled vehicles often have to cross streams and other inland waterways.
When this is required, it is important to know whether or not the water is too deep for the vehicle
to pass through without a special waterproofing kit. "Fordability" refers to the deepest water,
measured in inches, that a vehicle can pass through without adding the special equipment.
Because Army vehicles are expected to travel cross-country, over rough terrain, they must be able to
climb very steep hills. "Gradeability" refers to the steepest grade the vehicle can climb at a steady
speed in low gear on a smooth, concrete road when fully loaded.
All tactical vehicles must be able to climb a 60 slope under their own power.
This is the distance from the center to the rim of a circle made by the outside front wheel of a
vehicle when the front wheels are turned as far as they can go and the vehicle is moved in a circle.
One of your jobs as a wheeled vehicle mechanic will be to adjust the steering turning stops so that
the vehicle turns in the correct circle prescribed by the manufacturer.
This is the distance from the surface of a smooth parking area to the lowest component of the
As you know, when a vehicle is driven over rough ground, the oil pan, propeller shafts, or other
components might be damaged. Therefore, military vehicles are designed with much greater ground
clearance than civilian vehicles.
This is the ability of the vehicle wheels to hold to the road without slipping or spinning. Several
factors determine the amount of traction a wheel has, such as the condition of the tire and the type
of tire tread.