See Figure 1
If the lower ball joint is found to be defective, replacement of the lower control arm is required.
- Remove the lower control arm from the vehicle.
- Shake the ball joint stud several times. If movement is noticed, replace the lower arm assembly.
- Mount 2 nuts on the ball joint stud. Using torque wrench, turn the nuts and the stud of the ball joint while watching the torque measured on the wrench. This value is the ball joint starting torque.
- Compare obtained torque to the standard value of 26-87 in. lbs. (10 Nm).
- If the starting torque exceeds the upper limit of the standard value, replace the lower arm assembly.
- If the starting torque is within specifications, the ball joint can be reused, unless it has excessive play.
- A new grease boot can be installed using a large socket for a driver.
Shake the ball joint stud a few times, then install the nut to the stud and use a preload socket (MB990326 or equivalent) and an inch lb. torque wrench to measure the breakaway torque of the ball joint. The readings should be as follows:
- Compression lower control arm ball joint: 4-22 inch lbs. (0.5-2.5 Nm).
- Lateral lower control arm ball joint: 13 inch lbs. (1.5 Nm) or less.
- If the measured value is higher than the standard, the lateral or compression lower control arm must be replaced, as applicable.
- If the value is lower than the standard, check that the ball joint turns smoothly without excessive plate. If so, the ball joint is OK.
- Also, check the ball joint dust cover for cracks or other damage, if found, the control arm must be replaced.
REMOVAL & INSTALLATION
If the lower ball joint exceeds specifications, replacement is required. However, lower ball joints can not be replaced separately, but must be replaced with the lower arm, as a unit. Refer to lower arm removal and installation procedure in this section.