Two problems related to brake disc caliper have been reported for the 2011 Mazda CX9. The most recently reported issues are listed below.
There was a ratal sound anytime I would go over a bump or dip at any speed. The ratal got louder. I went to my mechanic and he said the calipers in the front had to be replaced. Specifically the driver's side it looked worn and there was rust so he thought moisture had got into the calipers. Thought this was unusal. So both had to be replaced in addition to my brakes. It also caused my brakes not to function correctlyl.
Approaching a red light on a dry sunny day, my brakes failed halfway through coming to a stop. At first my vehicle (2011 Mazda cx-9 sport with 56,000 miles) was slowing down normally and then suddenly there was grinding/crunching noises and despite pressing the break, the vehicle was no longer stopping. I slammed the breaks, pumped a few times, and the vehicle simply failed to slow down or stop causing me to slam into the rear of the vehicle in front of me. I took the car into a mechanic who notified me that both of my "front calipers were possibly defective," and my front rotors were "uneven and wearing on the outside. " however, my brake pads were good and did not need to be replaced. Good thing I was already stopping for the red light; therefore I estimate going about 10-15 mph (speed limit on street was 35 and I was already midway through coming to a stop at the light). Imagine if I need to break while going 60-70 mph on the interstate! or worse, driving in the rain!.