Lesson 2/Learning Event 1
FUNDAMENTALS OF AXLE ASSEMBLIES
Describe the fundamentals of axle assemblies.
Given information about the construction, operation, lubrication, and maintenance of axle
assemblies; types and principles of axle shafts; and principles of bevel gear differentials.
Answer 70 percent of the multiple-choice test items covering fundamentals of axle
Learning Event 1:
The term "wheeled vehicle" means that wheels are used to support the weight of the
vehicle and to propel the vehicle, not tracks, runners, or skids. To do this job, wheels
must be secured to a device that holds them in position so that they can roll and support
the load. This device is called an axle.
An axle is a cross-support between the wheels. The strength and design of an axle
assembly depend on what it is supposed to do. Think of a front axle, and you can see that
it must support the wheels so that they will roll and also turn in different directions for
steering. Now, think of a rear axle; it does not need steering ability, but it does have to
deliver energy to the wheels to make the vehicle move.
There are two major types of axles: the dead axle, used for the front of a vehicle if the
wheels are not powered, and the live axle for the rear where the wheels must be made to