Ball Joints! Upper and Lower Ball Joints
Ball joints are used to connect control arms to the knuckles which hold the wheel hubs or spindles. They are designed to allow the ranges of motion necessary for normal operation of a vehicle. They are essentially a metal rod with a ball on the end encased in a steel enclosure. Some ball joints are sealed and do not allow for greasing, while others are designed with fittings that allow regular lubrication.
The casing on sealed ball joints can crack, which will cause the interior to rust and fail. This is the most common cause of failure on these styles of joints. Issues elsewhere in the suspension can also take a toll on ball joints, as well as not regularly lubricating those ball joints which allow for it.
Replacing ball joints will vary in difficulty, and often it may be simpler to just replace the entire control arm. If you are unsure about how to proceed with a repair, always consult an automotive technician!
We have a large selection of ball joints from these manufacturers: