Road and wind noise too high even after sound deadening

[Johan Mer]

I have a T6 and the noise in the cabin is to high to be comfortable for me. Below 100 km/h it's mainly the road noise that's disturbing, above 120 km/h the wind noise takes over. The road noise varies quite a bit depending on the type of asphalt.
It is a 4MO panel van with left and right sliding doors running on rather quiet winter (and summer) tires.

I have put in 4 mm sound deadening in front wheel arches (from outside and inside), front doors (on and behind window carrier steel plate), on the sliding doors, panel sides, on the back wheel arches and back door. Not sound deadening on roof or floor though.
It is insulated with 12-20 mm closed cell foam all around. and have bulkhead in place.

What more could I do and is it unreasonably to expect it to come even close to a normal car?
Is it any difference between T6 and T6.1 or another model e.g. a multivan?

I have tinnitus, so that's the main reason I really need to get the sound level down.

Other than the noise I really love the van, but if I can't get the noise level down I have to sell it.

 

[DaveD]

I have a T6 and the noise in the cabin is to high to be comfortable for me. Below 100 km/h it's mainly the road noise that's disturbing, above 120 km/h the wind noise takes over. The road noise varies quite a bit depending on the type of asphalt.
It is a 4MO panel van with left and right sliding doors running on rather quiet winter (and summer) tires.

I have put in 4 mm sound deadening in front wheel arches (from outside and inside), front doors (on and behind window carrier steel plate), on the sliding doors, panel sides, on the back wheel arches and back door. Not sound deadening on roof or floor though.
It is insulated with 12-20 mm closed cell foam all around. and have bulkhead in place.

What more could I do and is it unreasonably to expect it to come even close to a normal car?
Is it any difference between T6 and T6.1 or another model e.g. a multivan?

I have tinnitus, so that's the main reason I really need to get the sound level down.

Other than the noise I really love the van, but if I can't get the noise level down I have to sell it.

I've also got a 4Motion with twin sliding doors. Mine is noisy compared to a car of the same value but I just accept that it's primarily a commercial vehicle, not a luxury saloon car, I think it's bound to be noisier. I think that a 4Motion is probably a bit noisier than a 2WD because it has more transmission components including a prop shaft running the length of the vehicle that turns even when the Haldex unit is not sending drive to the rear axle. It doesn't trouble me. I rarely go over 120KPH and usually I cruise at 110KPH.
I can't think what more you can do, tyres play a big part and I just replaced mine, which were nowhere near worn out, but they had become noisy, and like you it was very sensitive to different surfaces. The new ones are much quieter. Could you try swapping your wheels front to rear to see if that changes anything?
The wind noise is, IMO, a fact of life with a vehicle which has such a large frontal area and a bit of a blunt shape. Roof racks etc may make it worse.
I wonder if you can find a fellow Swedish T6 owner and compare vans - if his / hers is noticeably quieter you may have a specific problem such as a noisy wheel bearing that you aren't aware of.
Good luck, tinnitus is horrible and I hope you find a solution.
I can't advise you about a T6.1 but I'm sure others will.

 

[mmi]

HALOsonic - Active Noise Management Solutions

HARMAN, global leader & innovation pioneer in audio technology, offers HALOsonic suite of active noise management solutions, raising drive comfort & safety.

www.halosonic.co.uk

 

[Paynewright]

The biggest difference in mine was carpet lining all the wood panels and roof panel - stops the noise bouncing around - bit like fitting carpets and curtains in a house stops echo.

I’d even consider carpeting the bulkhead.

I used 4 way stretch carpet and high temp contact adhesive from Harrison trim supplies onto ply panels rather than the OEM hardboard panels.

 

[JOG]

@DXX recommends soundproofing the skuttle under the windscreen. (It does require removal of the wipers to get proper access)

 

[Johan Mer]

The biggest difference in mine was carpet lining all the wood panels and roof panel - stops the noise bouncing around - bit like fitting carpets and curtains in a house stops echo.

I’d even consider carpeting the bulkhead.

I used 4 way stretch carpet and high temp contact adhesive from Harrison trim supplies onto ply panels rather than the OEM hardboard panels.

Yes, I've considered making it plusher inside might help.

I've also got a 4Motion with twin sliding doors. Mine is noisy compared to a car of the same value but I just accept that it's primarily a commercial vehicle, not a luxury saloon car, I think it's bound to be noisier. I think that a 4Motion is probably a bit noisier than a 2WD because it has more transmission components including a prop shaft running the length of the vehicle that turns even when the Haldex unit is not sending drive to the rear axle. It doesn't trouble me. I rarely go over 120KPH and usually I cruise at 110KPH.
I can't think what more you can do, tyres play a big part and I just replaced mine, which were nowhere near worn out, but they had become noisy, and like you it was very sensitive to different surfaces. The new ones are much quieter. Could you try swapping your wheels front to rear to see if that changes anything?
The wind noise is, IMO, a fact of life with a vehicle which has such a large frontal area and a bit of a blunt shape. Roof racks etc may make it worse.
I wonder if you can find a fellow Swedish T6 owner and compare vans - if his / hers is noticeably quieter you may have a specific problem such as a noisy wheel bearing that you aren't aware of.
Good luck, tinnitus is horrible and I hope you find a solution.
I can't advise you about a T6.1 but I'm sure others will.

Yes, will at least go to a dealer and test drive a 6.1!

@DXX recommends soundproofing the skuttle under the windscreen. (It does require removal of the wipers to get proper access)

Yea, heard about that but thought it was more addressing engine noise, which doesn't bother much?

 

[JOG]

Yea, heard about that but thought it was more addressing engine noise, which doesn't bother much?

Noise is noise..........it all adds up!

 

[RedUn]

The biggest difference in mine was carpet lining all the wood panels and roof panel - stops the noise bouncing around - bit like fitting carpets and curtains in a house stops echo.

I’d even consider carpeting the bulkhead.

I used 4 way stretch carpet and high temp contact adhesive from Harrison trim supplies onto ply panels rather than the OEM hardboard panels.

This

Go for full plastic bottle insulation and then carpet all hard surfaces! Mines lovely and quiet now even at high speeds!

 

[Johan Mer]

This

Go for full plastic bottle insulation and then carpet all hard surfaces! Mines lovely and quiet now even at high speeds!

Promising!

HALOsonic - Active Noise Management Solutions

HARMAN, global leader & innovation pioneer in audio technology, offers HALOsonic suite of active noise management solutions, raising drive comfort & safety.

www.halosonic.co.uk

That's advanced tech!

 

[RunDSG]

@DaveD and @Johan Mer it could be interesting to compare decibel levels in our vans. I’ll happily record mine and share.

Yes, road surfaces will be different, and we can’t control weather, but it could be an interesting comparison.

If you want to try recording db at 80, 100, 120 km/h. I’m happy to do the same. There’s apps for iPhones and android that do this.

Call agree to all place our phones in the same spot in the cab.

 

[Graham Jones]

@DaveD and @Johan Mer it could be interesting to compare decibel levels in our vans. I’ll happily record mine and share.

Yes, road surfaces will be different, and we can’t control weather, but it could be an interesting comparison.

If you want to try recording db at 80, 100, 120 km/h. I’m happy to do the same. There’s apps for iPhones and android that do this.

Call agree to all place our phones in the same spot in the cab.

Good idea...I'll be in that.

 

[RunDSG]

Good idea...I'll be in that.

Had a go this morning…

On typical dual carriageway. Moderately smooth road surface.

Using phone mount holding my iPhone securely directly below rear view mirror. High as possible.

40mph 77dB
50mph 81dB
60mph 83dB
70mph 85dB

Rough patches made it jump 3-5 dB.

Used this very clever app.

‎Decibel : dB Sound Level Meter

‎Decibel Meter Pro is full of features sound level meter with exclusive accuracy of measurements and integrated Spectrum Analyzer. Calibrated with professional dB meter. The world is a noisy place: cars, power tools, crowds, machinery, and other common sources produce amounts of noise that can...

apps.apple.com

Doesn’t feel excessively noisy to me, comparable to my Golf, but I don’t suffer from sever tinnitus.

Now I think I need to do the same test in the Golf… hmmm…

 

[bobbybasic]

before/after sound deadening with measurements -

 

[Graham Jones]

Had a go this morning…

On typical dual carriageway. Moderately smooth road surface.

Using phone mount holding my iPhone securely directly below rear view mirror. High as possible.

40mph 77dB
50mph 81dB
60mph 83dB
70mph 85dB

Rough patches made it jump 3-5 dB.

Used this very clever app.

‎Decibel : dB Sound Level Meter

‎Decibel Meter Pro is full of features sound level meter with exclusive accuracy of measurements and integrated Spectrum Analyzer. Calibrated with professional dB meter. The world is a noisy place: cars, power tools, crowds, machinery, and other common sources produce amounts of noise that can...

apps.apple.com

Doesn’t feel excessively noisy to me, comparable to my Golf, but I don’t suffer from sever tinnitus.

Now I think I need to do the same test in the Golf… hmmm…

Well here are my results from an interesting morning testing

Using my phone, Samsung Z flip... app used. .Sound Meter by Splend Apps. Phone was hand held (by my understanding wife) head height between driver and passenger seats.
My van is 2018 T6 manual. LWB panel van which has carpeted floor and fitted out by myself, only for day camping.
We also tested my wifes' 2018 Polo , which we always loved it's quietness.
All figures are the Average shown on the app for each different speed.. as some bumps and rough sections made it jump, same as RunDSG.

Results..( figures in brackets are kmh. cause I'm in Oz.

T6 Polo

40mph (65) 78dB 79dB
50mph (80) 80dB 80dB
60mph (100) 81dB 80dB
70mph (110) 81dB 83dB

Just a thought, but this thread might be of interest in the Wheel and Tyres section. I am running Michelin LTX Trail tyres. Polo has Continentals.
Cheers.

 

[CJW]

The biggest difference in mine was carpet lining all the wood panels and roof panel - stops the noise bouncing around - bit like fitting carpets and curtains in a house stops echo.

I’d even consider carpeting the bulkhead.

I used 4 way stretch carpet and high temp contact adhesive from Harrison trim supplies onto ply panels rather than the OEM hardboard panels.

This matches my recent experience too. I was adding layers (deadening > insulation > floor > carpet lining > headlining) slowly over the last few weeks and drove it regularly in between. Each layer has a distinct effect. The deadening removes sources, sheet foam insulation attenuates, carpet and headlining absorbs. It was only at the final stage that I’d now consider the van quiet.

 

[JOG]

Sound deaden under the windscreen skuttle

 

[DaveD]

Sound deaden under the windscreen skuttle

I did my van in stages, one day the doors, next week another part, and so on.
The most noticeable improvement in noise levels came from sound deadening the scuttle panel.

 

[mmi]

The most noticeable improvement in noise levels came from sound deadening the scuttle panel.

Can you say what noise was reduced most by this - engine, wind, or even road noise?

 

[DaveD]

Can you say what noise was reduced most by this - engine, wind, or even road noise?

I think mainly engine noise (it was quieter stationary idling) but potentially a bit of road noise too.

 

[onlytheone]

I think noise on a transporter is just something that has to be put up with, my t6 is sound deadend and insulated to the hilt and converted camper so its carrying weight and is so friggin noisy, it really pisses me off, I think its more noticeable to me since my daily is a 45k luxury car with no noise at all, then I get in the T6 and sounds shit, I even put a new set of 17" Devonports back on, they did reduce it a fair bit after removing the 20"s and drives better.