Since I bought the xjr in October last year I've been tracking down a few creaks and rattles in the cabin.
These have included
1. the drivers door card; installed two missing grey clips, almost gone but still a little rattle left
2. the two speaker grilles either side on top of the dash; installed some small strips of foam backed tape, gone
3. drivers seat, outer lower plastic cover over the seat belt anchor, sprayed mating plastic tangs with silicone lubricant, almost gone, a small creak left

Its getting nice and quite now except for one noise that I'm having trouble with and is very annoying.
There's a creak coming from the top edge of the windscreen/windshield. Happens even when travelling over very small undulations. Its not the rear view mirror, headliner or sun visors. Happens on cold or hot days, takes a very smooth surface to silence it.

I'm suspecting slight movement of the windscreen/windshield trim finisher (Part nos C2C7977 (RH) and C2C7970 (LH) ) against the body of the car and or the glass.
In an attempt to get rid of it I've lifted the edge of the trim finisher, which is rubber, and sprayed silicone lubricant between it and the body and it and the glass but it hasn't improved things at all.

I know some will say get a life and just turn up the radio... but that doesn't work for me I'm afraid!
Any comments or suggestions gratefully accepted.

 

Not going to be the most helpful, but I have had previous experience with what I thought was a windshield creak. In the '70-'90 era General Motors A/B body there was a rubber bumper at the rear center of the hood (threaded into the cowl panel), which when it dried up with age had my car sounding like the windshield was going to shatter every time I went over a bump! I didn't believe my friend that said "it's that hood bumper right there" but sure enough, I changed it and silence.

Point being, I believe "windshield" creaks can originate from entirely different sources but the sound travels through the glass and will leave you chasing your tail.

Our Jags don't have any rear hood bumpers, but you may be onto something with the cowl trim panel. Are all the plastic clips in place? They all like to get brittle and fall apart at this age. Or maybe it's the mounting for the wiper motor or something else inside the cowl?

 

Well I had another go at this this evening.
This is the seal that I thought was the cause of the creaking. If I press the center of the trim with my finger I can hear the creaking inside the car.


I had squirted silicon lubricant under the rubber edge on the glass and body side of this trim piece and creaking was still there afterwards.
Tonight I lifted the edge of the rubber on the body side with my finger nail, got my little finger under the edge and filled with silicone grease all the way across the top of the windscreen from one side to the other. Wiped off the excess
Bingo! Took her for a drive over some crappy rough roads (don't have to go far for those in rural Ireland, in fact just outside my gate!) and the creak is gone ... deep joy!
I could tell that the rubber edge of the trim had been moving during the drive as afterwards some of the silicone grease had been forced out from under the rubber edge.