I have a 96 4Runner and a 98 Tacoma. With in the last year I have had both of these cars break a ball joint while driving, thankfully while in parking lots. I have not seen much warning either time. Maybe an overlooked pulling feeling in the steering the day before but that's it. Why are these breaking. I change my own oil so I am never looking at the suspension. Should I be greasing something? Should I take it to a shop to have it greased (how often). I am just kinda shocked these keep breaking and really don't want any more to break. Any advise or better knowledge on this is much appreciated. Thanks!