Hi folks, since Mazda HVAC systems have so many similarities across models, I though I'd post here instead of the Mazda5 forum.

My HVAC fan blows and operates normally, except it has begun making a deep rumbling noise. I don't know if this happened suddenly or gradually, as my son has been driving it for the last few months, but it started somewhere between 80k and 100k miles.

I changed the two cabin air filters, which turned out to be very dirty, hoping that would fix the noise, but it hasn't.

Anyone else have this problem? What was the fix and how much did it cost?

Thanks...