I have recently used a grease needle that fits into a conventional grease gun to inject grease into the ball joint cups , tie rod cups and far upper control arm cup on my C230 . I did this also on my former Ferrari Mondial QV . The difference is noticeable upon driving -- easier steering even with P/S . Is there really any reason to add lube though ? Seems the moving parts would wear slower . Bought the grease needle at Advance Auto .