Anyone who has experienced seat rattle/headrest rattle...
 

Was the issue corrected and how so?

My car is in now for this (also, mirrors keep ceasing to fold in, gauge cluster is rattling still after being "fixed" a week ago, outside door strip under the driver and passenger windows is rattling and loose) and they are not wanting to do anything regarding because they have a vehicle exactly like mine on the lot that just arrived and it has the same issue. They are claiming its because various parts of Mercedes are hand assembled therefore things are not as "tight" as machine would have done and that the seats move in all of them.
I told them I called an attorney (which I did, waiting on a call back,) I am tired of my BRAND NEW $60,000 vehicle being in service and having issue after issue!
I told them these cars rattle like crazy and they need to call Mercedes and make them aware, perhaps a mass recall is in order.

Sorry to hear of all of your issues. I had both my front headrests completely replaced. No more rattles for me as of now.

Both my headrests replaced.
Driver side had the rattle, passenger side wouldn't move F/R

Both done under warranty.

I took mine in for headrest rattle. It ended up being the control panel for the sunroof. I would have bet money it was the headrests, as the sound did not appear to be coming from the sunroof control panel. But, it was, so they replaced it.
It's now rattling again. And my driver's door trim where I rest my arm is now getting creaky. And I get an occasional noise from the instrument cluster- usually if I hit a hard bump or pothole. I was going to wait until my next service to have this addressed, but I'm going to take it in sooner. It's driving me nuts.
I drove my 2014 the other day for the first time in a while and it was so refreshing. Absolutely no noises.

A good way to find out if it’s the head rests is to give the seat a good punch when not sitting in seat. Strike it where your upper back would be.

If I apply pressure against the seat/hold the headrest back with my hand of someone is sitting in the seat it stops rattling.

That's definitely the headrest. There is known issue with a broken clip rattling inside the housing and should be replaced under warranty.

I've also just managed to silence every single squeak in the cabin and it's glorious. 3M squeak reduction tape FTW...

Has anyone stopped the display screen from rattling/creaking?

both headrest replaced under warranty. No push back from dealer, they just did it!

Fixed under warranty. I think they mostly put felt tape everywhere. No push back.

Seat is rattling again! Something in the dash around the center control panel area is rattling off and on and my shift stick is rattling. I am so over driving a $60,000 car that sounds like junk!! I really do not think that I will purchase another Mercedes vehicle again and I've owned three!I am so sick of my brand new car staying in the shop!

And what would be the point in filing for lemon law when the dealership states that all new C300s have the same issues?!

Is this not grounds for a recall of all new C300s?

If it's still under warranty, keep taking it back (a hassle I know) until it's resolved or MBUS buys it back.

I've got a slight, intermittent dash squeak, that only happens right before the auto-stop engages. Assumption is telling me it's maybe the recirc door closing, but I can't replicate it by manually engaging recirc.
Haven't had my headrest rattles return since both were replaced.

Is the shifter loose? Being a US-spec car, I'll assume it's the same column shift lever?

Worst case, what's the next closest MB dealer? Here in N Houston, I've got 2 about the same distance away, but 1 is markedly better than the other.

Yes, the shift lever is a bit loose. It going back in for service as soon as they have a loaner vehicle available. We have three dealerships in Louisiana , mine in Covington, one in New Orleans-does not provide loaner vehicles and one in Baton Rouge where I purchased my previous MB-every time I had my car serviced with them it was returned damaged.

I go to Biloxi.
Well run and good service so far.

Have not had need for loaner yet - but nice little shopping center behind with a NEWK's restaurant....

Crazy that an MB dealer doesn't do loaners, especially in a bigger city like N.O.
I don't know which, but my dealer is not corp. owned, and IIRC the people I've talked to say that the owner also owns one of the LA stores, but not sure which one.

Where are you located? Our NO location is owned by the Saints owners, the Bensons, idk who owns Baton Rouge and the Covington owners also own an MB dealership in Buckhead, GA.

I'm in N Houston. I think they also own the BR dealer & another here in TX.

I found an attorney. Lemon Law in Louisiana states, 44 days in service within 1 year or 4 times having the same issue and can not correct it. I've owned my car for 6 months, it's been in service 22 days and going back in on Monday. This will also be the 4th attempt at correcting two of the issues.

Best of luck.
Into another MB after buyback, if successful?

More than likely no, what's the point if they tell me and I've seen that all of the C300 Coupes have these issues?