Ball Joint Inspection
WARNING: This page is about a different car, the 2010 Mercury Milan, 2010 Lincoln MKZ, and 2010 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.
- Prior to inspecting the ball joints for wear, inspect the wheel bearings. Install a new wheel bearing as necessary. Refer to INSTALLATION .
- Raise and support the vehicle by the frame to allow the wheels to hang in the rebound position.NOTE: In order to obtain accurate measurements, the suspension must be in full rebound with the weight of the vehicle supported by the frame.
- Inspect the ball joint and ball joint boot for damage.
- If the ball joint or ball joint boot is damaged, install a new ball joint as necessary. Refer to REMOVAL AND INSTALLATION .
- Inspect the ball joint for relative movement by alternately pulling outward and pushing inward on the wheel and tire assembly, at the 12 o'clock and 6 o'clock positions, by hand. Note any relative movement between the wheel knuckle and both lower arms at the lower ball joints.
- If relative movement is not felt or seen, the ball joints are OK. Do not install new ball joints.
- If relative movement is found, continue with step 5.
NOTE: Do not use any tools or equipment to move the wheel and tire assembly or suspension components while checking for relative movement. Suspension damage may occur. The use of tools or equipment will also create relative movement that may not exist when using hand force. Relative movement must be measured using hand force only.NOTE: To avoid lateral movement of the steering linkage and steering components, make sure to apply hand force only at the 12 o'clock and 6 o'clock positions of the wheel and tire assembly. - To measure ball joint deflection, attach a suitable dial indicator with a flexible arm between the forward front lower arm and the wheel knuckle at the forward front lower ball joint.NOTE: In order to obtain an accurate measurement, the dial indicator should be aligned as close as possible with the center line of the forward front lower ball joint.
- Measure the ball joint deflection while an assistant alternately pulls outward and pushes inward on the wheel and tire assembly, at the 12 o'clock and 6 o'clock positions, by hand.
- If the deflection exceeds the specification, install a new forward and rearward lower ball joint. Refer to REMOVAL AND INSTALLATION .
- If the deflection meets the specification, continue with the procedure.
- Inspect the ball joint for relative movement by alternately pulling downward and pushing upward on the upper arm by hand.NOTE: Do not use any tools or equipment to move the wheel and tire assembly or suspension components while checking for relative movement. Suspension damage can occur. The use of tools or equipment will also create relative movement that may not exist when using hand force. Relative movement must be measured using hand force only.
Note any relative vertical movement between the wheel knuckle and upper arm at the upper ball joint.
- If relative movement is not felt or seen, the ball joint is OK. Do not install a new ball joint.
- If relative movement is found, continue with step 8.
- To measure ball joint deflection, attach a suitable dial indicator with a flexible arm between the upper arm and the wheel knuckle or ball joint stud.NOTE: In order to obtain an accurate measurement, the dial indicator should be aligned as close as possible with the vertical axis of the ball joint.
- Measure the ball joint deflection while an assistant pushes up and then pulls down on the upper arm, by hand.
- If the deflection exceeds the specification, a new ball joint must be installed. Refer to REMOVAL AND INSTALLATION .
- If the deflection meets the specification, no further action is required.