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Ball joint service: Insights and replacement tips for a variety of vehicle applications

Typically, lower ball joints experience load-carrying forces and are generally prone to wear sooner than upper ball joints, which are generally referred to as follower joints.
<p>Typically, lower ball joints experience load-carrying forces and are generally prone to wear sooner than upper ball joints, which are generally referred to as follower joints.</p>

Ball joint service isn’t always as straightforward as we’d like. Certain vehicles are prone to premature wear, some ball joints are not available separately from the OEM, theoretically requiring replacement of an entire control arm or steering knuckle assembly, and some are just downright difficult to access. In this article we provide insight and replacement tips for a variety of vehicle-specific examples.

Ford Transit Connect van

Lower ball joints on these vehicles have been known to fail after as little as 20,000 miles. The main issue is a weak plastic bearing that doesn’t hold up to the rough conditions of heavy usage in daily commercial service. In addition, the tightness of the area around the ball joint makes it impossible to grease the joint, eliminating the chance to flush away contaminants.

The OE ball joint uses an internal torx at the end of the stud. The knuckle must be removed in order to replace this joint, making this a two-hour job per side.

Not available separately

In many vehicle applications, an upper or lower ball joint may not be available from the OE source as a separate service part, requiring the replacement of an entire control arm or knuckle assembly. Aftermarket ball joint makers often have developed replacement ball joints that are designed for the application, eliminating the need to purchase a more expensive complete assembly.

Always check with your suspension parts suppliers on the availability of replacement joints in those cases where the OE does not offer joints separately. To cite only two examples, ball joint replacements are not available through the OE for 1996-2005 Ford Taurus and Mercury Sable station wagons, or 1989-1997 Mazda Miata MX5 vehicles. However, aftermarket replacement ball joints are readily available with superior design and construction from aftermarket sources such as MOOG.

Just because the OE doesn’t offer ball joints separately for a given vehicle, never assume that you’re forced to buy a complete suspension assembly. Always check with your aftermarket sources.

Ford Super Duty and Dodge Ram

These vehicles that are equipped with straight axles are originally fitted with non-greaseable lower ball joints. Due to the commonly severe duty use, a quality greaseable joint is required during replacement. In addition, improper installation can lead to a variety of steering issues as well as ball joint failure.

All straight axle and twin I-beam designs have manufacturing variations: horizontally between the upper and lower taper holes in the knuckle/axle and between the mounting locations of the upper and lower ball joints.

Plastic doesn’t last long

Vehicles equipped with polymer bearing surfaces don’t provide sufficient load-carrying capability, especially in rough service environments. Examples include Ford Expedition, Explorer and F-150 Heritage, F-250 and Ranger, Lincoln Navigator, Mazda B2300 and B3000 and Mercury Mountaineer vehicles. Load stress and debris contamination can quickly erode the bearing surface, and water contamination can corrode the ball stud and housing.

When installing a replacement ball joint, technicians may note that the new ball joint may not fit tight in the opening in the lower control arm. The lower ball joint hole has been known to experience wear, especially when the ball joint has been replaced several times. If a traditional ball joint is installed in this situation, it will move and shift during operation, which can quickly damage the control arm in addition to causing unsafe handling. Lower ball joints in these applications are difficult to press out.

When removing, an air hammer or chisel is not recommended, as these tools can further damage the control arm ball joint receptacle. A specialty press tool (MOOG’s T40003 is but one example) should be used to avoid mushrooming the housing of the old ball joint and damaging the control arm.

GM light-duty truck ball joints

The original equipment upper ball joints on 2007-2011 GM light-duty full-size pickups and SUVs feature an integral joint (part of the upper arm) with a non-greaseable plastic design and a 1.062-inch ball joint stud. This design has been prone to premature failure in as little as 36,000 miles. Aftermarket upper arm/ball joint assemblies are available with a larger diameter ball and higher-quality greaseable ball joint.

Lower ball joints on 2002-2007 Chevy Trailblazer and GMC Envoy, 2002-2004 Oldsmobile Bravada and 2004-2007 Buick Ranier feature a relatively small diameter stud ball and an OE-style polymer bearing. In severe conditions load stresses (in addition to water and debris contamination) quickly erode these bearings. Aftermarket (non plastic) joints are available, but be sure to remove the old OE-style ball joint flange during removal of the original joint. The flange must be bent upward with a hammer and chisel before attempting removal.

Pressed-in lower joints

Dodge Caliber and Jeep Compass vehicles feature a lower control arm that incorporates a pressed-in and crimped lower ball joint. The OE service manual recommends replacing the entire control arm. However, aftermarket lower ball joints are available for these applications.

Using a suitable press, press the original ball joint down and out of the control arm. Replacement (greaseable) ball joints are available with a larger diameter flange that press into the control arm in the downward direction (same direction as pushing out the OE joint).

Tags: Mike Mavrigian  Moog 
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