Build-a-Ball Joint Rock KrawlerThe Rock Krawler Build a Ball Joints were used in our Early JK long arms and on TJ long arm systems when the front upper was on the driver side connected to the stock housing location. We do not use or recommend grease on the build a ball! Grease attracts more dirt and debris then it is worth while doing more harm to the joint itself. We simply recommend putting in a few drops of 3 and 1 oil every time you perform an oil change.