Hi all, my cabin fan sounds like a helicopter and steering wheel vibrate on mode 3 , maybe I should mention that I have replace the windshield at the mercedes, and after this the problem began ..
crossfire 2004 automat

 

I can't help you there. My first guess is debri in the fan blower.... but you say the steering wheel is shaking too. I have no idea!

 

Second that opinion.
The whole dash in the truck that I just got shook when the fan was moved to the 3rd & 4th position. Figured the fan cage was tore up. Got home researched the vehicle and fan noise and sure enough there was a fix. Removed the truck's fan and there was a very small piece of plastic (1/2") and that was all it took.
So, remove your fan (don't know the proceedure) and let us know what you find!

 

I removed the fan once on the Crossfire. Very easy to do. Just a few screws to remove and the whole unit drops down. You can feel around in there for any debri. Also check the cabin air filter while you are in there.

 

I haven't done that either! One of these days!

 

Second this. I had to figure it out one night when I had loud noises were coming from mine. Took it out, found one of those twirly tree seeds and an acorn in it.

 

My car sat in the garage at home and in a garage at work. I never parked it under a tree and always babied the car. After 3 years I took the cabin filter out (very easy to do). I was shocked at the garbage in there (mostly leaves). I have no idea how they got in there with the way I take care of the car. It is good to replace the cabin filter once in a while.... or at the very least take it out and clean it.