Excessive Cabin Noise

[pguest]

I have a 4 year old Avensis T3x on 16" alloys which has done less than 9000 miles because people will not use it due to excessive road noise which booms through the cabin. So it also has had 3 owners before 3000 miles I wonder why? I thought I can fix this, and the car was then half list price may 2010. I tried carefully sound insulating the hatchback with foam and stick on pads... no use! I changed the tyres from Dunlop sport 3000 to Michelin Alpin which helped the mileage no end but still noisy. I think I am stuck with the complicated rear suspension and perhaps neoprene bushes which are more like metal to metal. I have written to Mr T to see what he says, but has any other member changed rear bushes or sway bars or anything for a result that they did not expect in terms of cabin noise?

[acetip]

I have a 4 year old Avensis T3x on 16" alloys which has done less than 9000 miles because people will not use it due to excessive road noise which booms through the cabin. So it also has had 3 owners before 3000 miles I wonder why? I thought I can fix this, and the car was then half list price may 2010. I tried carefully sound insulating the hatchback with foam and stick on pads... no use! I changed the tyres from Dunlop sport 3000 to Michelin Alpin which helped the mileage no end but still noisy. I think I am stuck with the complicated rear suspension and perhaps neoprene bushes which are more like metal to metal. I have written to Mr T to see what he says, but has any other member changed rear bushes or sway bars or anything for a result that they did not expect in terms of cabin noise?

are you using the correct tyre pressure,is the foot pump or garage tyre inflator accurate.are your tyres what are described as low profile,which tend to be harsher.some makes of tyres tend to be nosier than others.tyre reviews wil advise road noise each make produces on a scale.next year al new tyres will be marked as to the noise they produce.but this can vary from car model the tyre is fitted to.

[cmia]

Booming noise,

could be bearings.

[pguest]

I did all the things like tyre pressure and making sure that they go the correct way round and jacked up and checked for bearing noise last year and again this year. It is a puzzle as the booming is like the floor pan was vibrating in stmpathy on certain types of road and there are lots of them in Anglesey. This is where you redo the road by covering it with tar pouring on small stones and sweep up the ones that dont stick. This is a very noisy surface. On smooth surfaces its as quite as a mouse. I wondered if the rear suspension had seized somewhere but it does depress with weight and the shocks appear to be working. Sell it and move on...that means its beaten you...no way!

[caveman_si]

Thinking along a different line have you checked to see if the window are all orginals? Some aftermarket windows dont provide the same sound deadening as the factory fit ones, and might not be something mechanical at all?

Ive had an issue with a replacement front window in that it made the car significantly louder. Had a bit of a fight with the insurance co and glass co but got it change to a toyota spec window in the end. Now the sound is fine again.

[Jamesbelfast]

Have you checked the interior roof liner. Could be a panel or lining vibrating at certain fequencies.

[pguest]

Thanks for the ideas, but I have found that underneath the body and petrol tank are protected from the heat generated by the exhaust by thin sheets of tin which if you strike them vibrate. It seems like health and safety overkill and by using self adhesive sound deadening I have actually altered the cabin noise. This is ongoing, a filthy job and I long for a pit, but they may be vibrating in sympathy. I wonder if anyone has removed them with a good result? I cannot imagine the car catching fire, the earlier model did not, but I know someone will disagree.