Finally got my c300 Sport last week and it drives great. i will post pics of it soon. Took it on the highway the other day and noticed it sounds like a window is cracked open when driving. Definitely more noise than my other vehicles. All windows were up, doors were closed, sunroof was closed. Im going for a couple hundred mile drive tomorrow and will try to pinpoint it but most likely Im gonna have the dealer look at it. Any ideas? Is this normal? Just seemed like too much road noise to me especially since I don't remember the test drive being like this. It sounded like a window was not all the way up. Everything else is great. I love taking turns at 40 mph

 

The big mirrors are most likely your problem, they tend to make a lot of noise if its windy outside. Other than that you might have a bad seal on one of the windows or doors, but I'd go with the mirrors first.

 

I thought that might be the problem after reading everyones posts about the mirrors but it seemed like a door or window wasnt sealing correctly. Tomorrow I will see if it comes from one side of the car or both sides. If its both sides, most likely its the mirrors but it sounded like it was coming from the passenger side. Thanks again

 

It's a known issue with the W204. I brought it up with my service advisor on our A-Service and he said MB knows about it but there isn't a TSB out for it yet. Our car has done the same since day one, happens at about 68-70 mph.

-Ryan

 

If that the case, will they issue a fix?

 

What the he77... I thought I was the only one. I kept thinkin to myself how this is one of the loudest cars (at highway speeds) I've ever ridden in, but people kept saying this is their quietest car ever... I thought it was just me.

Now I kno I'm not

 

They should have mounted the mirrors lower, on the door.

 

Yeah it's the mirrors. At highway speeds they produce lots of wind noise. You could try aftermarket mirrors if you can't live with the noise...or turn your radio up

 

When I first picked it up I heard a wind whistle from the drivers rear door area. Wife and daughter couldn't hear it. When I brought the car in for the 1000 mile check up I told the SA about it when I picked up the car he told me they had to do a minor adjustment to the drivers side rear door no whistle now.

 

any complaints about the mirrors - blame the euro-safety-crats for mandating them, along with the foolish upright grills designed to "save" pedestrians from impacting the hood.