Rear windshield rattle?

[E92TiAg335i]

Hey guys.

Recently picked up a mint sub 40k mile 1 owner M4 from major dealership.

Car is super clean, however, under heavy acceleration/deceleration, i noticed the car makes a TON of rattle noises from the rear window.

Anybody know how to fix this/what could be causing this?

[tanzm4_]

Originally Posted by E92TiAg335i

Hey guys.

Recently picked up a mint sub 40k mile 1 owner M4 from major dealership.

Car is super clean, however, under heavy acceleration/deceleration, i noticed the car makes a TON of rattle noises from the rear window.

Anybody know how to fix this/what could be causing this?

In my case with my f82 it's the housing around the brake light which can be fixed if you put some felt tape around the seal or make sure you back seats are fully latched.

[MIA_F80]

Originally Posted by E92TiAg335i

Hey guys.

Recently picked up a mint sub 40k mile 1 owner M4 from major dealership.

Car is super clean, however, under heavy acceleration/deceleration, i noticed the car makes a TON of rattle noises from the rear window.

Anybody know how to fix this/what could be causing this?

Happened to mine twice and both times it was one of the tires having uneven thread, as you accelerate it rattles all the way back to the car. Check the tires, almost positive that's the case.

[E92TiAg335i]

Originally Posted by MIA_F80

Happened to mine twice and both times it was one of the tires having uneven thread, as you accelerate it rattles all the way back to the car. Check the tires, almost positive that's the case.

I'll check but they're brand new

[hlm2c]

Could be the black plastic pieces above the seats that you can flip up to reveal a hook (maybe for baby seats).. Installing a piece of felt tape in between the edges and on top of the hook can help.

Or for me, my dash cam installer, when tucking the wires away on the rear right corner of my car hastily put back a section of the C pillar back incorrectly, leaving part of it unhooked on the inside so it rattled during my cold starts until I went back to re-adjusted it. Now it's solid and rattle free again.

[FlyingLow78]

I’ve had the majority of my car’s rear seat interior apart to fix all of the rattles. I found noises around the third brake light cover, the speaker grills, the child seat anchors, the c-pillar trim, the seat latches, the backrest anchors, the entire rear deck lid, and even the airbag mounts.

[LVI]

Originally Posted by FlyingLow78

I’ve had the majority of my car’s rear seat interior apart to fix all of the rattles. I found noises around the third brake light cover, the speaker grills, the child seat anchors, the c-pillar trim, the seat latches, the backrest anchors, the entire rear deck lid, and even the airbag mounts.

Is there anything that WASN’T rattling back there?

[jcortez75]

Here is the felt tape I used to quiet down all the rattles in my f36: https://amzn.to/2YLnDT9

I also went ahead and added felt tape on all the door storage bins since the lining is all plastic. Anything I stored in them would rattle like craze.

Another key area is the storage unit on the underside on the driver-side. I store several sunglasses, probably more than I can fit, either way since the inside housing is all plastic, it rattles like crazy.

[E92TiAg335i]

Bump. Anybody else?

[HyeM3]

Do you have an aftermarket exhaust? If so check and see if that metal brace that holds the midpipe in place is rubbing against the exhaust. Mine does and on rough roads it rattles against it and causes vibration in the cabin that sounds like it's coming from the rear windshield

[bsmf8x]

Yes it's either the speaker or brake light housing, I deal with it too

[overfreeze]

It's the 3rd brake light housing. I took it to a dealer for them to fix and they put some felt tape on the inside of the panel. It helped a little bit, but it didn't completely go away. It only happens on bumpy roads or during hard acceleration. Super annoying.

[E92TiAg335i]

Originally Posted by overfreeze

It's the 3rd brake light housing. I took it to a dealer for them to fix and they put some felt tape on the inside of the panel. It helped a little bit, but it didn't completely go away. It only happens on bumpy roads or during hard acceleration. Super annoying.

Damn! Not sure if there is any kind of DIY for this. This is interesting.

[N1rve]

How do you guys even hear rattles under heavy acceleration over the screaming of the passengers and being yelled "NO!! Slow down!! I hate this!"? Maybe I need to get my ears checked.

[E92TiAg335i]

Originally Posted by N1rve

How do you guys even hear rattles under heavy acceleration over the screaming of the passengers and being yelled "NO!! Slow down!! I hate this!"? Maybe I need to get my ears checked.

Only when I have my girlfriend or mother in the car 😂

[bsmf8x]

Originally Posted by E92TiAg335i

Damn! Not sure if there is any kind of DIY for this. This is interesting.

Originally Posted by overfreeze

It's the 3rd brake light housing. I took it to a dealer for them to fix and they put some felt tape on the inside of the panel. It helped a little bit, but it didn't completely go away. It only happens on bumpy roads or during hard acceleration. Super annoying.

You guys tinted? They remove the housing to tint for me and I think it had to do with that, as on the 4 series forum they have the same issue with tinted cars.

I'm going to do the felt tape. Keep in mind the 4 series forum all bought some new clips that broke from getting tints but our cars don't have the same set of clips, and they won't fit so don't order those like I almost did lol.

[E92TiAg335i]

Originally Posted by bsmf8x

You guys tinted? They remove the housing to tint for me and I think it had to do with that, as on the 4 series forum they have the same issue with tinted cars.

I'm going to do the felt tape. Keep in mind the 4 series forum all bought some new clips that broke from getting tints but our cars don't have the same set of clips, and they won't fit so don't order those like I almost did lol.

Can you post a DIY of the tape method?

[overfreeze]

Originally Posted by bsmf8x

You guys tinted? They remove the housing to tint for me and I think it had to do with that, as on the 4 series forum they have the same issue with tinted cars.

I'm going to do the felt tape. Keep in mind the 4 series forum all bought some new clips that broke from getting tints but our cars don't have the same set of clips, and they won't fit so don't order those like I almost did lol.

Yep, my rear window is tinted. It started rattling after I got my tints done, so removing the panel was probably the cause. I wonder if buying a new panel would fix the issue.

[bsmf8x]

Originally Posted by E92TiAg335i

Can you post a DIY of the tape method?

if my rattles are 100% gone then yes. I hear it like crazy if I floor the car with the windows up and music below 50%. So I'll test it with music off and if it's a proper fix I'll post up my method, otherwise if it doesn't make a big difference then no point.

[E92TiAg335i]

Originally Posted by bsmf8x

if my rattles are 100% gone then yes. I hear it like crazy if I floor the car with the windows up and music below 50%. So I'll test it with music off and if it's a proper fix I'll post up my method, otherwise if it doesn't make a big difference then no point.

Amazing! Yes, I hope it fixes it.

From what you described— this is 10000% my exact issue.

[ONEof500]

Originally Posted by overfreeze

Yep, my rear window is tinted. It started rattling after I got my tints done, so removing the panel was probably the cause. I wonder if buying a new panel would fix the issue.

They likely broke the blue center clip when removing the housing. Replaced that clip plus some felt tape no rattle.

[ONEof500]

This is the part

https://www.ecstuning.com/b-genuine-...SABEgId_vD_BwE