Rear area rattle

Hello everyone, I have a quick question. I recently got a 2008 528i with 52000 miles and I am in love with the car.

The car is very solid and rides very quietly. There is however a moderately loud rattle coming from the rear area when going over bumps. I originally thought it was the deck behind the rear seats (where the speaker sits) but I was wrong.

I found out that if I push straight up on the rearmost roof trim next to where the back windshield starts, it silences the rattle. It takes moderate pressure, not just placing my hand on it. My guess is that it is either the actual rear windshield molding or the trim there are to blame. Going off of the information I've told you, what would be the most likely problem and solution?

On mine it was the third brake light housing. I took it apart and worked on it with hot glue and stuffed in bits of felt.

Felt has fixed all the interior rattles for me.

Great, thank you for the advice. Any tips on taking it apart?

Originally Posted by Tomahawk674

Great, thank you for the advice. Any tips on taking it apart?

The headliner/cover just pulls off and the light itself is locked in with a plastic slider - no tools needed except maybe something to pry against the sliding locking tab if it is a bit too tight.

Ok, I got the small cover off, but I still don't know how to remove the brake light. Any chance I can get a little more detail? I'm looking everywhere for a diagram but I can't find one.

Great, I was able to get the center brake light off. There are two little pieces of felt on each end, which look worn down. I'll try replacing those.

I have a 2nd rattle, super simple: The cover for the light in the driver foot well is ever so slightly loose. How do you remove that cover? (like you're trying to change the bulb inside I guess).

Those foot well lights just have a slot on one end that you pry against to pop it out.

As you learn to do more you will be surprised how much comes apart with no tools!

Well, the good news is that I fixed the rattle up from from the footwell light. The bad news is that the rattle from the rear is still present, and it was not the brake light assembly (took the light off and drove around, still makes a pop/crack sound when going over deep enough pot holes). It is not from the deck, the sound eminates from there the top of the rear windshield meets the roof.

I am really thinking it's the rear windshield vibrating. If I wanted to have an auto glass shop take the rear windshield out, and re-install with all new seals, what parts would I need?

I've found the part for the exterior molding, but I've heard there's more.

Try the rear arm rest/cup holders. It made an awful racket on mine. Lower it down and have someone sit in the back pressing on parts.

You can have them also press on the rear glass, headliner, etc.

Rattle remediation is a 2 person job, takes lots of perseverance but it really does pay off!

Listen to NoQuarter, the man knows of what he speaks. Good luck Bro

I have already sat in the the back pressing on things. The only time the rattle stopped was when I pushed straight up on the center brakelight. Considering the light is completely off of the car and I still hear the creaking, I think it is the fact that I was pushing on the actual rear windshield.

I've heard that the sound could be the windshield rubbing against the body of the car. I am going to try spraying some silicone oil around the perimeter and see if it helps. The creaking sound is very similar to the sound an airliner makes when the body flexes during take off or turbulence.

I was just able to find how the noise occurs. If I press on the piece of metal that's right above the center brake light, I can hear it. It's like I can hear the metal and glass touch or something.

Originally Posted by Tomahawk674

I was just able to find how the noise occurs. If I press on the piece of metal that's right above the center brake light, I can hear it. It's like I can hear the metal and glass touch or something.

I have a rattle in my 545 as well. Thought it was from the rear, then the middle then one day finally isolated it. It was the moonroof bug shield that pops up when you retract the moonroof all the way back. The shield looks like its made of some metal and always hit the moonroof when I go over bumps or dips.

Originally Posted by E60black

I have a rattle in my 545 as well. Thought it was from the rear, then the middle then one day finally isolated it. It was the moonroof bug shield that pops up when you retract the moonroof all the way back. The shield looks like its made of some metal and always hit the moonroof when I go over bumps or dips.

You can fix that rattle simply and cheaply, just take some of those rubber pads that are used on the bottom of lamps and things to keep them from scratching tables stick one on each end of the bug shield and one in the middle, this will keep the metal from hitting the glass and eliminate the rattle.

My rattle is definitely the rear windshield itself. If I knock the windshield itself from the outside I can hear the rattle from the outside. If I have someone press and hold the windshield while I knock it, the rattle sound is gone.

I'm going to have an auto glass shop re-install it.

RATTLE FIXED!

Took it to a windshield specialist. He took my rear windshield off, and said that nothing was really out of sorts. I bought new rubber seals that go around the glass on the outside, which the guy installed; the guy did say the seal that sits on the bottom of the windshield was rather worn.

He put some foam around where the windshield contacts the body/trim and the rattle is officially gone.

Originally Posted by Tomahawk674

RATTLE FIXED!

Took it to a windshield specialist. He took my rear windshield off, and said that nothing was really out of sorts. I bought new rubber seals that go around the glass on the outside, which the guy installed; the guy did say the seal that sits on the bottom of the windshield was rather worn.

He put some foam around where the windshield contacts the body/trim and the rattle is officially gone.

Congrats, hopefully it's gone forever now. If you ever need to replace the window trim rubber again (without needing to fix the rattle) just do it yourself, takes about 20 mins.