See Figure 1
Ball joints are pressed into the lower control arms and cannot be removed. In the event of a defective ball joint, the lower control arm and ball joint must be replaced as an assembly.
Defective ball joints are determined by checking the rotational torque with a special preload attachment and spring scale. Torn ball joint dust boots can be replaced. Replacement of the ball joint dust boot is accomplished by removing the lower control arm from the vehicle and chiseling off the old boot. Coat the inside of the new dust boot with lithium grease and press it into the ball joint using the proper tool. Check the ball joint stud threads for damage and repair as necessary. Check the ball joint preload and install the lower control arm by reversing the removal procedure. Please refer to the Lower Control Arm Removal and Installation procedure in this section.
Rear Wheel Drive GLC and 1979-82 626
- Check the dust boot for wear or cracks, and replace if necessary.
- Raise the vehicle until the wheel is off the ground. Grab the tire at top and bottom, then alternately pull it toward you and push it away to check for ball joint end-play. Wear limit is 0.04 in. (1mm). If necessary, replace ball joint and control arm assembly. See control arm removal and installation procedure above. When installing ball joint nut, torque to 43-51 ft. lbs. (58-69 Nm) on the GLC and 46-69 ft. lbs. (62-93 Nm) on the 626.
- Raise the vehicle and support it securely. Remove the front wheel.
- Unbolt the ball joint where it connects to the lower arm. Put the hook of a spring scale in the outer bolt hole. Turn the ball joint back and forth several times and then measure the rotating torque on the spring scale. Turn the joint slowly and make sure the scale stays at 90 degrees to the joint lever. Rotating torque should be 6.3-10.9 lbs. Otherwise, replace the ball joint.
This procedure is usually done with a preload attachment tool, such as Mazda No. 49-0180-510B or equivalent . Do not attempt to make this test without the proper tool.
- Raise and support the vehicle safely. Remove the wheel.
- Remove the cotter pin and nut (which secure the tie-rod end) from the knuckle arm, then use a puller to separate the tie-rod from the knuckle.
- Unbolt the lower end of the shock absorber.
- Remove the nut, then withdraw the rubber bushing and washer which secure the stabilizer bar to the control arm.
- Unfasten the nut and bolt which secure the control arm to the frame member.
- Check the ball joint dust boot for cracks and tears. Replace as necessary.
- Shake the ball joint stud a couple of times before measuring the preload. Check the amount of pressure required to turn the ball stud, by hooking a pull scale into the tie rod hole in the knuckle arm. Pull the spring scale until the arm just begins to turn, this should require 4.4-7.7 lbs. on the 626, MX6 and 1986-89 RX-7, 1-2.2 lbs. on the 1986-87 323, 4.0-6.8 lbs. on 1988-89 323 and 1.1-2.6 lbs. on the 929. If the reading is lower than 1.2 lbs. on the 1979-85 RX7, replace the ball joint and the suspension arm as a unit.
REMOVAL & INSTALLATION
Rear Wheel Drive GLC and 1979-82 626
Refer to the Control Arm removal and installation procedure. When installing the ball joint nut, torque it to 43-51 ft. lbs. (58-69 Nm) on the GLC or 46-69 ft. lbs. (62-93 Nm) on the 626.Front Wheel Drive GLC
- Raise the vehicle and support it securely by the front crossmember. Remove the front wheel.
- Remove the pinch bolt and nut from the bottom of the strut. Pull the ball stud out.
- Remove the two bolts attaching the joint lever to the lower control arm, and remove the assembly.
- Install in reverse order. Check and adjust front end alignment, if necessary.
See the following procedure for lower control arm removal and installation. If the ball joint is defective, the control arm and joint are replaced as an assembly.