Chrysler 300M Service Manual page 45

2 - 12 FRONT SUSPENSION
LOWER BALL JOINT (Continued)
The ball joint used in the lower control arm of this
vehicle is a sealed-for-life ball joint and requires no
maintenance lubrication. The ball joint cannot be ser-
viced separately from the lower control arm. If the
ball joint is determined to be defective it will require
replacement of the complete lower control arm. Refer
to DIAGNOSIS AND TESTING in this section for
proper testing of the ball joint.
NOTE: The ball joint does not require any type of
additional lubrication for the life of the vehicle. No
attempt should be made to ever add any lubrication
to the lower ball joint.
OPERATION
The ball joint is a pivotal joint on the lower control
arm that allows the knuckle to move up and down,
and turn with ease.
DIAGNOSIS AND TESTING - BALL JOINT
Raise front of vehicle using jack stands or a frame
contact hoist until front suspension is in full rebound
and tires are not in contact with the ground. Grasp
tire at top and bottom, and apply in and out force on
the wheel and tire. While applying force to the tire,
look for any movement between the lower ball joint
and lower control arm. If any movement is evident,
the lower ball joint is worn and the lower control arm
requires replacement. The ball joint is not serviced
separately.
LOWER CONTROL ARM
DESCRIPTION
The lower control arm is a steel forging with 2 rub-
ber bushings and a ball joint (Fig. 1). The bushing
isolating the lower control arm from the front cradle/
crossmember is a metal encased pivot bushing. The
bushing isolating the lower control arm from the ten-
sion strut is a solid rubber bushing. The lower con-
trol arm is bolted to the cradle/crossmember using a
bolt through the center of the pivot bushing. The ten-
sion strut is fastened through the center of the ten-
sion strut bushing and lower control arm. The lower
control arm ball joint connects to the steering
knuckle.
OPERATION
The lower control arm supports the lower end of
the steering knuckle and allows for the up and down
movement of the suspension during the jounce and
rebound travel.
DIAGNOSIS AND TESTING - LOWER CONTROL
ARM
Inspect the lower control arm for signs of damage
from contact with the ground or road debris. If the
lower control arm shows any sign of damage, inspect
the lower control arm to see if it is bent.
The only serviceable components of the lower con-
trol arm are the pivot bushing and the tension strut
bushing. The lower control arm is serviced as a com-
plete assembly otherwise. Do not attempt to
repair or straighten a broken or bent lower
control arm. It must be replaced.
REMOVAL - LOWER CONTROL ARM
(1) Raise vehicle on jackstands or centered on a
frame contact hoist. See Hoisting in Lubrication and
Maintenance.
(2) Remove the wheel and tire assembly from the
vehicle.
(3) Remove the ball joint stud to steering knuckle
attaching nut and bolt (Fig. 24).
Fig. 24 Control Arm To Steering Knuckle
1 - LOWER CONTROL ARM
2 - BALL JOINT STUD
3 - CLAMP NUT AND BOLT
CAUTION: Pulling steering knuckle out from vehicle
after releasing from ball joint can separate inner
C/V joint. See Driveshafts.
CAUTION: When lower control arm is separated
from steering knuckle, do not let ball joint seal hit
up against steering knuckle. If ball joint seal hits
steering knuckle, seal damage may occur. If ball
joint seal becomes torn, replace seal before assem-
bling lower control arm to knuckle.
LH