The connections may only need tightening to eliminate
leaks; however, leakage may occur at various points in
the power steering unit if the seals are defective.
Power steering (fig. 3-2) adds the following
Document conditions and report them to the mainte-
components to the steering assembly: a hydraulic pump,
nance shop for replacement of any defective seal.
a fluid reservoir, hoses, lines, and a steering assist unit
whether mounted on the linkage or incorporated in the
The types of steering troubles that develop in
steering gear assembly.
vehicle operations that should be documented and
turned in for repair are as follows:
Excessive play in the steering system
Vehicle pulls to one side when braking
Front-wheel tramps (high-speed shimmy)
Tires squeal on turns
Improper tire wear
Hydraulic power is used to turn a whole section of
a machine on a vertical hinge. This design is called
articulated steering and it is controlled by a steering
wheel, a hydraulic control valve, and hydraulic
cylinders. (See fig. 3-3.) The pivot is midway in the
vehicle, so both parts share equally in the pivoting. This
action produces the effect of four-wheel coordinated
steering, such as the front-and-rear wheels run in each
others tracks, backward and forward.
Wheeled equipment may be designed to steer by
angling the front wheels, the rear wheels, and or both
These problems must be documented and turned in
the front-and-rear wheels (fig. 3-4). Front-wheel
steering is the standard method. The vehicle follows the
Figure 3-2.-Power steering linkage assembly.