Hey all, I have a problem that started around 30k miles. Now have 52k miles, so driven it for awhile with no breakdown. There is a humming noise that comes from the front end somewhere while the vehicle is under power. It starts at low speed and becomes very noticeable around 25mph. Its ridiculously loud at highway speed. It's not a continuous hum though, it rises and falls in pitch with the speed of the motor, not the wheels. I know it is not the tires, I had those changed about 10k miles ago and it didn't make any difference whatsoever. It's not the motor, if I am at highway speed and put it in neutral and hit the gas, it doesn't make the sound at all. I think its either in the front diff, the tranny, t-case or possibly a wheel hub. The morons at the dealership were completely stumped as well as some other mechanic shops, which has led me to many wasted days trying to figure this out. I'm about a week away from just getting rid of the stupid thing and buying something new. Any help would be greatly appreciated.

Matt

 

Sorry,
Its a 2008 CX-9 Sport AWD with the basic alloys.

 

hey have you figured out what it was? i am having the exact same issue and mechanics are unable to locate the problem