Well, I ordered some sound deadening today as part of this project
I went with Silentcoat, a progressive company that specialises in this field and offers products in Silentcoat, Dynamat and Dodo mat variations.

I opted for the Silentcoat 2mm bulk mat as the initial mass loading material to assist with panel resonance.
Iys got a really sticky back that adheres well to the panels and adds bulk reducing and tinny noises / resonant rattles.
Silent Coat 2mm Mat Bulk ? Sound Deadening Shop

This will be topped with Dodo liner CCF9 which is a closed cell foam with excellent Thermal and Accoustic properties ideal to reduce noise, insulate the vehicle and to isolate barriers and trim panels.
Dodo Liner CCF9 Pack ? Sound Deadening Shop

The plan is to completely cover the boot, spare wheel well area and wheel arches.
Between this and the add on door seal I'm hoping to significantly reduce any unwanted noise in the cabin as much as possible.
Hoping to get started on this in the next few weeks

 

Jim
If you get your car too quite inside, you could fall asleep while driving.

 

Lol, point taken Jay.
On some long distance runs sometimes covering 600 - 900 miles in some days I've came close to nodding a few times.
The car's not the noisiest by any means, but there's definitely a little wind noise still, but mostly road noise I want to eliminate as much as possible.


Onwards n upwards mate

 

I should clarify, it's by no means a noisy car, I'm simply looking to make improvements to existing
As noted before, we did some trial runs with duck tape and a sound meter app, which was inconclusive, but db ratings were around 73db - 74db

Having tried a piece of A4 paper by opening the door and inserting, then closing the door I find that there is little, in fact almost zero resistance, where there should be some if it's a good seal.
This is true even on the drivers side door, where I've replaced with an OEM door aperture seal at around £100 iirc, quite disappointing

To be honest I'm not a huge fan on non OEM add ons / mods etc, but willing to try this in regards to the door seals.
Its's basically a £50 gamble of sorts approx.
The plan is to add the 3m seal to the door aperture adjacent to the existing, as well as add it to the door leading edges as shown in the video.......My hope is that it performs as it should and creates a definitive seal whereby the paper or similar will have resistance to the point of tearing. This will tell me that the seal is effective, should reduce wind noise and aid to a quieter drive.

I agree that the bulk of the noise is mostly road noise from the big 20" wide low profile tyres, so sould be worth looking at doing the front as well as the rear arches
Once that's done and the sound deadening arrives, I'll be removing the entire rear carpet and body shrouds etc adding the Silentcoat to the floor, spare wheel well, rear wheel arches, seat back and underside of the parcel shelf probably. The 2 prong method of the deadening mat stuck firmly to the body adding substance / weight followed by the acoustic liner really should help.

I'll do a few runs afterwards and should know to what degree if any I've succeeded almost by ear but will try the sound meter app again of course.

The ideal would be to remove the interior and coat the entire inside, the doors and even the roof, however, unlikely I'll go that far.
I may go down the route of cladding the inside of the doors at some point, but we'll see....

 

Looking back at some of the sound readings we done some time ago and wanted to share.
At some points we found decibel readings ranging from 64db to 73 - 74db when travelling at 70mph approx.
This wasn't totally scientific, more of a pointer, but differences like certain road surfaces and weather conditions would also obviously have to be taken into account.

Please see charts and graph below that show the meanings so they can be taken in context.




Realistically I'd like to be in the "moderate rainfall" area....lol

 

Hello Jim, did you already get the 3M tape? Been thinking about applying something like that to the drivers door as there's absolutely more wind noise there then on the other side. Otherwise I think the XJ is a pretty quiet car, especially the V8. I once managed to try to restart the engine when it was already running!

Guus

 

Hi Guus, yes I already have the 3M tape, but haven't had the time to fit it yet I'm afraid. Also really don't want to be fitting it in cold weather, need to wait until the temp gets a little higher for best results.

Noise levels - To be honest I think it's noisier than it should be at speed, between wind noise and tyre road noise for a car in its class and want to make it better


"Having tried a piece of A4 paper by opening the door and inserting, then closing the door I find that there is little, in fact almost zero resistance, where there should be some if it's a good seal.
This is true even on the drivers side door, where I've replaced with an OEM door aperture seal at around £100 iirc, quite disappointing

To be honest I'm not a huge fan on non OEM add ons / mods etc, but willing to try this in regards to the door seals.
Its's basically a £50 gamble of sorts approx.
The plan is to add the 3m seal to the door aperture adjacent to the existing, as well as add it to the door leading edges as shown in the video.......My hope is that it performs as it should and creates a definitive seal whereby the paper or similar will have resistance to the point of tearing. This will tell me that the seal is effective, should reduce wind noise and aid to a quieter drive.

I agree that the bulk of the noise is mostly road noise from the big 20" wide low profile tyres, so sould be worth looking at doing the front as well as the rear arches
Once that's done and the sound deadening arrives, I'll be removing the entire rear carpet and body shrouds etc adding the Silentcoat to the floor, spare wheel well, rear wheel arches, seat back and underside of the parcel shelf probably. The 2 prong method of the deadening mat stuck firmly to the body adding substance / weight followed by the acoustic liner really should help.

I'll do a few runs afterwards and should know to what degree if any I've succeeded almost by ear but will try the sound meter app again of course."

 

You could feed 1/4" tubing through the weather stripping if the weather stripping on the Jag allows. Get a little soap and feed it the tube through, it will fill the "dollar bill void" nicely. The door will be a little firmer to shut but the wind gap will close and the car will be quieter.

Cheers,
Griff

 

Thanks Jim. On My car drivers side is definitely noisier then the passenger side. I read that you already replaced the seal without much improvement and since mine still looks good I'm not going to invest in that. Let us know if the tape helps!

Maybe Griff's idea on the hose is an option too or some other fill.

Guus

 

Yes I've also considered this as an option too....see here.....
<iframe width="854" height="480" src="https://www.youtube.com/embed/4XR-J7VTN80" frameborder="0" allowfullscreen></iframe>

 

Well, the sun was out, a nice day and after my "head cleared" somewhat.....big night last night for daughters' 30th, I decided to tackle the add on door seal.

Here's a few videos below, the product is shown in an earlier post. The videos show the door seal, pre add on product and seal obtained.
The product in place, and also the end result

Check out the existing door seal prior to adding the add on version

Here's the add on door seal in place

door seal fitted - YouTube

Here's the paper test afterwards

after door seal - YouTube

It seems like a real improvement.
I took a test drive and definitely seems better wind noise related, now have to address the tyre road noise with the sound deadening.


The doors seem to close tighter, forming a better seal as you'd expect. There's almost a "sshhh" noise as I open the door like I'm releasing a vacuum somehow.
Onwards n upwards


Jim

 

Well, finally got around to making a start on my sound deadening, emptied the boot, that was a feat in itself.....lol
Then carpet removed and everything was vacuumed out and cleaned up ready to start.......

I started around 12.30 pm and didn't finish until around 6.30pm so took a fair old while, unsure if it was me being slow or what, but didn't expect that long........
I used Silent Coat 2mm sound deadening Silent Coat 2mm Mat Bulk ? Sound Deadening Shop
It's a really nice sticky self adhesive product with a nice finish, applied all over and stuck well with the use of a roller. I stopped at this and may add the Silent mat later....we'll see.....

here's a few pics








Then put the carpet back in place and loaded up as normal and went for a run to test.
Certainly made a difference in a positive way and glad it's done n dusted, out the way, may look to add the Silent mat at a later stage.

Thanks
Jim