mk0155

First off, many thanks to Kev525 who explained how this is done in this post
https://5series.net/forums/topic/235...4&#entry259384
I am quoting verbatim much of what Kev525 has already posted but with photos and hopefully my insights will help as well. I'm unable to improve on how Kev has explained it so why try.
The process for removing the non fold-down rear seats is very simple.
First thing to do is to remove the rear bench seat by pushing it backwards and upwards to release it off the two clips that hold it down.
Next thing is to get a torx socket (T50) and remove the seatbelt anchor bolts at the base of the seat back - one each side and two in the middle. Put the seatbelts up on the parcel shelf out of the way.

Close up

Undo the two smaller torx bolts (T40) which are located just above the two centre seatbelt bolts and which hold the bottom of the seatback in place. (located either side of the armrest at the base of the seat-back).

Now go into the boot of the car and release the two catches on the underside of the parcel shelf nearest the seat-back by inserting a pointed screwdriver into the recess and pushing it as per the instructions on the PDF file, shown below.

The part to push is a circular catch to which a spring is attached. Do not touch the spring. See below for the initial position of the catch before you rotate and release the pressure on the spring.

This photo shows the position of the catch when it's released. Note you can now see the spring.

Once the seat-back has been released from inside the boot you can pull the seat-back forward from inside the car. It will pop out when the 2nd catch is released. There are two metal curved locator pins on the bottom at each side which will just allow the seat to "roll" upward when you pull it forward.
Here?s a pic of a locator pin at the bottom of the seat

Here's where the locator pin is seated

This now gives access to the parcel shelf where it clips onto the metal underside in the top of the boot space.
Release the parcel shelf by popping the plastic lugs upwards and out of their holders.
Once these clips are out there is enough slack to slide in some thin foam between the parcel shelf and the metal base which the seat catches are bolted onto. I left enough sticking out to fold it down so that it covered the squeaky foam which sits between the metal support and the seat-back itself. (I used the sort that you lay between laminate flooring and concrete base which I had left over from a job I did in the house last year).

Alternatively buy some felt from a fabric shop, £6 for twice the amount needed. I did not release the parcel shelf and instead pushed the felt using screwdriver into the gap between the foam below the parcel shelf and the steel beam show in the pic.





While the seat is out, you may want to just see if the catches need to be moved backwards slightly to ensure that when the seat is clipped back in, that it's a tight fit. (2 torx bolts on the underside where you released the seat-back in the boot).

Refitting the seats is the opposite process, except you just locate the seatback at the bottom (using the curved matal locator pins) and then simply "snap" the top of the seat into the catches by pushing firmly backwards from inside the car.

Check where the locator pins are seated, this spot was rusted on my car, probably because it's beside the door (rain ingress) and the pins have scraped the metal due to body flexing. See the photos below to see what I mean. The locator pins were rusted slightly. I used wd40 to clean and heavier oil to lubricate. These may have been a culprit for the noise. A short cut for this whole procedure - take the bottom seat cushion off and lubricate the locator pins and see if this fixes the squeak.





Hopefully when everything is back in place, no more squeaks.