Sorry for double posting. Phone will not let me edit my post. How many are effected by the water pump issue? Is it super wide spread? I didnt see any TSBs on it..?
it's a well known Ford design flaw .... it's not a Mazda engine in the 2013 CX-9, it's the Ford Duratec 3.7L engine
https://www.fordf150.net/forums/viewtopic.php?t=120721
this unfortunate owner had a 2013 CX-9, engine failed at 61,000 miles due to water pump seal failure and coolant leaked into the engine case....
https://www.carcomplaints.com/Mazda/CX-9/2013/cooling_system/water_pump_failure_led_to_engine_failure.shtml
the problem is the water pump blade is made of plastic and starts deteriorating and starts to wobble which in turn stresses the blade axis and causes the seal to fail and allows coolant into the engine cavity
see video below :36 second mark , just a sheer madness design, one side of water pump is coolant other side is engine oil, water pump is buried deep inside on the side of engine block, so it's not an easy job to replace, it can be done, but you need the right tools and experience.
If O-ring seal break coolant start leaking, tell tale sign is if you keep seeing coolant level dropping for no reason.
There should be no coolant drop, it is a closed loop system.
So, in the above links where owners aid there was no warning prior to engine failure, that's not true, all they had to do was check the coolant level on a regular basis, they would have noticed the coolant dropping dangerously low.