88 Auto Suspension and Steering
shown in Figure 5-9, is a plate that contacts the body when
the strut rod attempts to move downward past a certain
point.
To protect the piston rod from water and dirt, a
dust cover, or dust boot, may be installed over the rod,
Figure 5-10. On some vehicles, the dust cover and bumper
are a single unit.
Other parts of the MacPherson strut wheel assembly
include a lower control arm and ball joint, a strut rod, and
a sway bar. Figure 5-11 shows a typical MacPherson strut
wheel assembly. Most MacPherson strut systems use a
single-mount lower control arm and a strut rod. Some
systems, however, have a lower control arm with two
frame mountings. The moving parts of the suspension are
isolated from the frame and body by rubber bushings.
MacPherson Strut Variations
On a small number of vehicles with MacPherson
struts, the basic design has been modified somewhat to
Bumper
Coil
spring
Strut
Nut
Washer
Upper stop
Spacer
Upper
mounting
Bearing seat
Bearing upper washer
Bearing seal
Bearing
Bearing lower washer
Bearing spacer
Coil spring
upper seat
Coil spring seat
Strut cover
A
Nut
Ball bearing mount
Shaft Strut assembly
B
Figure 5-3. A—Exploded view of a MacPherson strut assembly. Note the strut mounting bearing and other related parts. B—Upper
end of strut is free to move on a ball bearing mount. (General Motors, Hyundai)
Nuts
Washers
Shock tower
Strut
assembly
Figure 5-4. The MacPherson strut upper mounting is generally
fastened to the inner fender. (General Motors)