Removing road noise?

[nielshm]

I think the Auris is pretty well build, and wind and engine is very low. But road noise or wheel noise is pretty loud, even with Continental tyres. In two months, winter tyres are put on, making noise sooo much worse. I'm thinking about getting some rubber plates to isolate the outside wheel noise from the cabin. The only question is, where is the best place to place this sound barrierer? Any one with experiense in sound isolation in Toyotas? 

[eygo]

you could try this company

 

https://www.nkgroup.co.uk/product/car-soundproofing-full-kit-no-engine-blanket/

[Gerg]

This was originally an info only website about car sound proofing, now they sell their own materials there as well:

https://www.sounddeadenershowdown.com/

Some of the principles recommended above relate to the materials used by the people in eygo's link above.

Some years ago, I fitted some of what they (above) call CLD, to the boot, bonnet (hood), doors, wheel arches and roof of a Mazda 6, to reduce road noise (I know it's an Auris you are asking about, but similar build).

I installed it in stages, so I was able to judge what area was most effective in reducing road noise. There was road noise improvement from each stage, and the doors and bonnet closed with an expensive-sounding thunk; all the panels sounded like they were made of wood when tapped.  But road noise was not reduced as much as I expected or wanted.  Overall, it was a bit disappointing, and no one place stood out as a particularly effective area this to fit this to.  To fit the CCF and MLV is harder and time-consuming, and the MLV layer needs to be as air-tight as possible (in the same way that a window that is not fully closed lets in a lot of sound).

In the end I sold the car before I could consider fitting the CCF and MLV.

I think in general, if there were any cheap and simple fixes for road noise, then they would have put them on at the factory.

I have managed to look in a partially stripped, new Range Rover, on the one I saw they used a CCF and MLV sandwich (that is pre-shaped) on the rear wheel arches.

My diesel Skoda has a mat that is effectively CCF and MLV that covers the bulkhead and some of the front wheel arches. But I don't think the Skoda is that good for road noise.  But, fitting some Dynamat (CLD) under the bonnet on the Skoda was cheap and very easy, and did make a small but worthwhile difference to engine and road noise. Not remotely as much as I think you are looking for, though.

HTH.

[Gerg]

I finally got around to popping the driver's door card off to fit some Dynamat to the door skin.

I have only done the one door so far, given the time of year, who knows when the other(s) might get done?

I used about one square foot of Dynamat, cut into strips to fit in between the door reinforcement bars. I think that is well under £10 worth.

A surprisingly good result, better than I expected. The road noise noticeably reduced (to me, not noticed by the wife), so is engine noise. The door doesn't go 'twang' when closed - more like a German car now. The car feels more solid - and I've only done one door!

I wonder if the un-damped door space was working like an amplifier?

This result is obviously extremely subjective, and I have no dB numbers to back it all up.

HTH

[Countrylad]

I noticed quite a lot of noise from my 2014 Auris Touring when I first bought it, especially on country lanes, and it didn't take very long to figure that stuff pinging up from the road surface was responsible for the noise. Much worse than on my old VW Passat - and for a while we wondered whether we'd made a mistake in buying the car?

I fitted a set of four mudflaps (the kosher Toyota ones, which weren't pricey), and it fixed the problem entirely. I understand that it might be costing me as much as 1 or 2 mpg because of the extra wind drag, but that's okay by me. And I've grounded the front flaps on kerbs once or twice. Darn that road-hugging chassis!

"I think in general, if there were any cheap and simple fixes for road noise, then they would have put them on at the factory."

I think there is huge pressure on car manufacturers to get the wind drag factor down, so as to reduce their emission levels and reduce the owners' VED bills, so they leave obvious stuff like mud flaps out. That way, it's up to the owners to decide whether they want to do anything about it. Most don't.

 

[Gerg]

I was thinking about sound deadening more than anything else. I never considered mudflaps!

It is often said that the best way to reduce road noise is to try to stop it at source.  I would never have thought that mudflaps would help here by getting close to the where it is being created.

I wonder if the flaps are diverting the airflow (with the sound energy in it from the tyre contact patch) away from the car underbody, so there is less opportunity for it to pass into the car body? 

I know what you mean about the VW.  They do 'heft' very well, I'm surprised they are not heavier than they are.  The job I did yesterday would have been a completely different proposition if I'd been doing it in the Skoda (been there).

As it was, I was looking to find out if there was something loose or broken in the driver's door, the sound when closing it was that bad!  I thought maybe there was an unsupported ECU or something.  In the event, there was nothing, but the moisture membrane had not been fitted properly at the factory, as witnessed by some water marks near the door speaker.  And it is always interesting to see how it is all made.

In the event, if I could find nothing wrong (apart from the above), then I thought I'd put some cut rectangles of Dynamat (aluminium backed bitumen-type sheet) on the door.  Toyota had thoughtfully put two tiny pieces of sound deadening (?), one behind the speaker and the other by the door handle.  They didn't seem to do much.

My problem with my Auris, is that with such a (until you accelerate briskly) refined powertrain, the car could benefit from a quieter cabin.

There is another way I think I detect that the general sound level has changed:-  the dash squeaks are a bit more obvious, and I can hear the other traffic (passing the other way) a bit more clearly.

I mentioned the Range Rover as it was brand new, and a quiet, luxury car, interesting to see how it might get to that point.

Having said all that, over time, I have driven Lexus LS400, LS430, GS350, IS300 and CT200.  I didn't think any of them were *that* quiet.

Maybe I just have hyperacusis?

 

[Countrylad]

45 minutes ago, Gerg said:

I was thinking about sound deadening more than anything else. I never considered mudflaps!

It is often said that the best way to reduce road noise is to try to stop it at source.  I would never have thought that mudflaps would help here by getting close to the where it is being created.

I wonder if the flaps are diverting the airflow (with the sound energy in it from the tyre contact patch) away from the car underbody, so there is less opportunity for it to pass into the car body? 

I think it's just that the floorpan on my Auris used to ping and clatter more from thrown-up road dirt and vibration than any other car I've ever owned. And the narrow sills and the cutaways at the bottoms of the doors probably mean that some of the dirt doesn't just hit the floorpan at right angles but gets spattered up the sides of the car - hence the noise. I wasn't comfortable with the thought of grit -blasting my paintwork!

Anyway, it only cost me about twenty five quid to fit the flaps, and everything on the car was pre-drilled to accept them, so it was a forty minute experiment that paid off. (For me, at least.) Apologies if I've hijacked your thread.  And good luck with the soundproofing.

Noisiest car I ever owned was a solid little Rover that had had its side pillar bent and repaired after a side impact. The doors were correctly fitted and gas-tight, but the roof rumbled at speed! Summat just wasn't happy in there - the bash must have stretched a few welds, I suppose?

What was I to do about it? I was still making up my mind, when some very kind gentleman broke in and stole the car. That was one less thing I had to worry about.