Sponsored by:

Fixing rear window rattles

Old 09-27-2013, 10:20 AM
Thread Starter
Join Date: May 2012
Location: Somerset West, South Africa
Posts: 175
Default Fixing rear window rattles

Cross posted from 6Speed

I have finally gotten down to fixing the last rattles on my 991 after the Porsche workshop failed to remedy the problem - so I had a go.

Sorry - no pictures - when I get going, I get going. But it's simple and I have tried to describe it as best as possible. Holler if something is not clear.

Fixing rear window rattles on the 991

One of the most common sources of rattles on the 991 are the rear windows. The windows are mounted in a floating frame held onto the body with a plastic tab on the rear end (the narrow part of the glass), a similar tab on the top (about the middle of the glass) and two nuts which hold the two window adjusters which are located top and bottom on the front side of the glass at the B pillar.

There are two sources of rattles - the first is the contact area of the bottom frame to the body work. Nothing holds this in place so it can
move freely resulting in possible squeeks and rattles when driving over rough surfaces.

The second source relates to the top of the window and the plastic peg. The glass may be slightly loose in the frame here - and that does not

To identify if you have a rattle simply work your way into the rear seats and tap the glass from the inside firmly with your finger and listen
to the sound. If all you are getting is a thump then you don't have an issue here. If you get a "thump" followed by a "krr" everytime your
finger bangs the glass then it's time to do some work. Do this at various places over the glass - you'll get the hang quickly.

It's fairly easy to perform the fix. You need only very basic tools. You need to find a 1/2 inch wide stip of very thin double sided tape (not
much more than the thickness of a sheet of paper. I found some nice stuff in an art shop). The length of the strip is about 3/4 the length of
the rear window you want to fix. You may also need a piece of rubber fuel hose (the stuff sold in spares shops). About an inch is what you are
looking for.

The double sided tape goes between the bottom of the rear window frame and the body work. For this the window has to come out just a little bit
so you can place the tape. This is simple:
Remove the plastic trim piece where the seat belt goes in (B-Pillar). Simply pull it out - it just clips in. Now remove the B-Pillar trim - again, just pull it out towards you (right angles to the pillar) - it just clips into place. You now see two nuts (one is hidden by the seat belt). These hold the window adjusters in place. Remove the nuts. Don't turn the adjusters (you need to stick an allan key into them to turn them if needed).

Now lightly push the rear window at the bottom outwards and it comes out about 1-2 inches (the top of the window remains in place). Stick a bunched up cloth into the gap to hold the window open like that.

Now take the opportunety and clean the underside of the window frame and the exposed body work so your double sided tape will stick better.
Place the tape on the underside of the exposed window frame as far back as you can get it in - don't worry if you can't get the tape all the way
to the rear part of the frame (that is still connected at the back so it gets tight there).

Once the tape is ready remove the cloth and place the window back - there is a small locating pin at the bottom of the window at the B-Pillar. During this
manouver push the frame up so the double sided tape does not stick prematurely onto the body while you are still moving the frame.
Once back in place, put the two nuts back while applying downwards pressure into the frame from the outside to help the double sided tape bond.

If all is well the frame will now no longer move when you push outwards on the glass from the inside.
(Side note: You could also consider a thin bead of clear slicon instead of the tape, don't use too much in case the frame ever needs to come out).

Note the B-Pillar trim has 4 metal clips. Take some lithium grease (or thick silicon grease) and apply a good bit on each. This will prevent the
clips from vibrating if they aren't completely tight (they seldom are). Now clip the trim pieces back into place.

Repeat the tapping. All good ? Concentrate on the top part of the window now. If you hear a bit of "Krr" there it's time to use the fuel line.
Feel with your fingers around the top of the window behind the roof liner (there is quite a gap there and the roof liner is flexible). At around the middle of the frame you should be able to feel the small plastic pin that holds the top of the glass in place. That is about where you are going to simply force in the piece of rubber fuel line. Note there is a fairly wide gap between the glass and the body work - all along the top.
The rubber fuel line fits in nicely with just the right force and it applies permanent pressure to the glass pressing it against the frame so
there is no chance of a rattle here.
(Side note: You can also consider stuffing a length of foam into the gap)

Good so far ?
Now get moving on the other side of the car...
Rainier_991 is offline  
Old 09-27-2013, 10:34 AM
draxa's Avatar
Join Date: Aug 2006
Location: Kent, England
Posts: 882

Thank you, Rainier; you are a man after my own heart! I, too, am fixated by rattles and squeaks.
My first 997 was perfect bar a slight buzz/rattle from the instrument binnacle. Man, I tried everything - including the Porsche fix of tape inside the mounting screws - and my favourite of some felt crammed in the join. (I find most of these internal rattle issues can be remedied with (a) felt, (b) WD40, (c) an elastic band or (d) a spot of Presstick) but in this case I finally admitted I was beaten.

My second 997 was completely silent, even after 30,000miles.

My current 991 is behaving well - after almost a year - except for the driver's seat which seems to squeak when I move in it PARTICULARLY during warm weather. This is a small issue which I can live with.

I will hold on to this 'fix' you have provided above just in case.......
draxa is offline  
Old 09-27-2013, 11:53 AM
Join Date: May 2003
Posts: 722

Porsche seat squeaks are usually the seat belt receptacles.
Easy to isolate but surprisingly difficult to eradicate!
WCE is offline  
Old 09-27-2013, 12:11 PM
Thread Starter
Join Date: May 2012
Location: Somerset West, South Africa
Posts: 175

Originally Posted by WCE View Post
Porsche seat squeaks are usually the seat belt receptacles.
Easy to isolate but surprisingly difficult to eradicate!
Porsches fix is to clad them with thin self adhesive felt. This works well for the rear.
The fronts however are a bit more tricky.
I fixed mine by simply readjusting the neck. Loosen a bolt below and behind the seat where the neck ends and rotate as far back as possible - this allows the plastic receptacle to clear the leather so it does not come into contact with it - that contact creates the squeek and inaddition will wear the leather at that spot quickly.

Also - sometimes the insides of the receptacles can start to rattle. You can try squirting a bit of WD40 in there - usualy helps for a while.

Rainier_991 is offline  

Thread Tools
Search this Thread
Quick Reply: Fixing rear window rattles

Contact Us - About Us - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to and affiliated sites.
  • Ask a Question
    Get answers from community experts
Question Title:
Your question will be posted in: