300blackout

Ever since I installed larger aftermarket wheels with low profile tires my car developed a annoying rattle in the hatch.
I spent countless effort to find the source. I Plastidipped the metal tabs that hold the plastic hatch under cover, I tried felt tape, insulation, etc.

Well, I finally found the source. It's the LED third brake light.

xbox

Yep.

Realised that 6-months ago, with lots of help from DraggonRR

https://mbworld.org/forums/amg-gt-gt...ml#post7279633

300blackout

Thanks xbox. Sure wished I saw that post earlier, much earlier. At least the rattle is gone now

Surge

Unfortunately, @DragonRR 's photo is no longer visible, and he's not replying. Can someone else post of photo of the 3rd brake light rattle fix? I have tried putting some cardboard between the light and the glass. Didn't really work...

Mazspeed

I could use the photo as well, having same issue. Thanks

JSwan724

If you are still under warranty, it is important to take the car to the dealer and have the service department write it up and log it in the Factory GT database.
If there isn’t a fix already, the factory may develop one and make it availble to everyone.

FWIW; Besides helping the next owner who has the problem, it’s the way several “fixes” have come about. One was the protective screens on the intakes that are now standard. Ask me how I know.

Regards

Jerry

Surge

What they did at the dealership in my case was remove the panel and add felt/fabric tape between them. You can also add those round adhesive backed pads between the trim pieces as an interim solution, to see if the sound goes away.

I no longer think the rattle is coming from the hatch area. The service tech used the Chassis Ear and thinks it’s the passenger side hood hinge. I also think it could be one of the roof trim pieces (it runs parallel to the glass or carbon roof panel). Getting that checked this morning.

JSwan724

Surge
Have you tech check the shock mounting brackets and shock both extended and closed. If the shock looses its gas/pressure it’s gonna rattle.

Regards

Jerry

Surge

Thank you Jerry, will do!

Currently waiting for a new hood hinge to be installed. If you press down on the hood when closed, at the corner close to the windshield, right above the hinge, you can wiggle it on one side. That’s where the tech thinks it’s rattling.

hhcheng23

My car was in dealer for the hatch rattling last week.
Dealer replaced the third brake light, and left/right/rear trim panels, and apply felt tape at contact area.
Hatch area is rattle free now.
Rear control arms are also replaced due to squeaking over speed bumps.

Jason

Just had the felt job done to the 3rd brake light Friday. I thought they had it until I got on the highway and it's as bad as it was. Will call them Monday.

Surge

Update:
my rattle has been fixed! It was indeed one of the hood hinges that was rattling.

Oddly, the rattle 100% seemed like it was coming from the rear, not the front.

If you have a rattle check your hood as follows:
with the hood closed, grab the corner above one of the hinges (at the base of the windshield). Try to pull the hood corner up and push it down. See if it has play. Mine had about 1-2mm, not much; but that’s what was causing a metallic rattle when going over bumps.

Jason

Hmm so a rattle that sounded like it was coming from the trunk was actually coming from a hinge at the front hood by the windshield?

Surge

Yes! I didn’t believe it until the work was done.
I think it’s due to the aluminum space frame(?) chassis, sound travels in this car differently than in traditional body on frame cars.

Jason

Dealer isolated and fixed my noise in the trunk. Figured I’d add details in case it can help anyone. Seems we all have different culprits. Mine was the “Rear Trunk lock motor making noise”, mb part# 190-740-23-00. Noise is completely gone finally and such a relief as it was annoying.