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If you want to keep them from wearing out fast or just falling out. You can take a piece of fuel line tubing and cut a small sliver off the end of it and put it in the drive cups. That will help to keep the dog bones from moving around and wearing out too fast or falling out. You don't the slice of fuel line tubing too big our it will bind up the dogbone on the uptravel. So make cure to lift the arm up and turn the wheel to make sure there is no binding.