I posted the following message over at a Edmunds.com Mazda 5 forum and someone told me about this place and gave me a link so I could visit to let me know that I wasn't alone with this problem. And boy am I glad I came over and joined. I, too, have the same front suspension crunching/grinding noise and this is what I posted:
Hey, all!
I'm wondering if anyone has experienced the following: My Mazda5 produces an ugly sounding crunching, grinding noise from the front suspension whenever it is cold outside and I go over a large bump of some sort like a speed bump or a deep undulation where the suspension really articulates. It only happens when it's cold out, and since I live in NYC and we're in winter it gets cold out here.
I took it to my Mazda Service Center - and my 5 is still there - and they have checked everything out and said that everything is fine with the car and that they didn't find anything broken or worn or anything in the front suspension. Of course, I asked: "Then why is it making such a noise?" They explained the same thing to me that they explained the first time I took it a couple of months ago (see, I was growing worried since the noise was very disconcerting to me), which is that the type of suspension that the 5 has (E-type) can make noise in the cold whether when the rubber components rub against the metal components and in the cold it makes a harsh noise over larger bumps.
They said that whenever I go pick up my car that they will put it on the lift for me and take me under it to explain what they mean. I look forward to that, but in the meantime I wonder if any of you - especially the ones in Canada where it's really cold - have experienced this.
On a side note, my car has a strange tapping noise emanating from the dashboard anytime I go over any size or type of bump on the road at at least 20mph. The tapping is not obviously heard by passengers not familiar with the car unless you pay close attention to it, but it drives ME and my wife absolutely INSANE - especially at night when I like to drive in peach and quiet and all I hear is tap, tap, tap over any road irregularity. They are taking my dashboard apart to try and find the noise since one of their "technicians" finally heard it when I took him along for an umteenth road test. Previously, they thought I was crazy since they weren't able to hear anything, but this time around the tapping/clicking noise was pretty obvious. Anyone experience this?