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 reading should be 3–22
inch lbs. (0.3–2.5 Nm).
If the measured value is higher than the standard, the upper control arm
must be replaced.
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.
Fig. 1: Measure the torque of the ball joint to see
if it needs to be replaced
Also, check the ball joint dust cover for cracks or other damage, if found,
the upper control arm must be replaced.
