One problem related to sway bar has been reported for the 2007 Mazda CX9. The most recently reported issues are listed below.
Two weeks ago I brought in my car due to noise and steering issues. The right ball joint was found to be very loose and about to fail, so it was replaced. The mechanic looked at the left ball joint and determined it was tight and therefore did not recommend replacement. Yesterday, while driving, the left ball joint failed. My tire got wracked and locked-up sending me into a skid. I had to be towed. The axle broke, plus the sway bar, strut and control arm all need to be replaced, between the two repairs, the cost is quite high. This could have been deadly at high speeds.