After almost 10 years of running larger tires and off-roading, the factory ball joints on this 2009 JK rubicon have reached the end of their functional life. rather than replacing them with factory replacements we decided to upgrade them to the Dynatrac ProSteer Ball Joints. http://www.quadratec.com/products/56100_200X_PG.htm?utm_medium=video&utm_content=dynatrac_balljoint_install