Moog K500134 Ball Joint Problem Solver patented cover plate design allows for tighter tolerances vs. traditional cover plate designs, providing a more durable and extended life part. Exclusive cover plate protects against contaminants leaking into the bearing surface. Moog engineered steel composition results in a stronger component Greaseable socket design allows new lubricant to flush contaminants from the assembly, reducing corrosion and wear Loose or worn chassis parts can lead to premature tire wear