Road Noise

[sam82]

Hello

I have a 3 week old X3 35d and the road noise is terrible when comparing to my old Volvo.

Is this is a common no issue with X3s? or do I need a visit to dealer?

[X5Sport]

Common with all recent X’s in my experience.  BMWs are noisier due to removal of sound deadening and addition of runflats.  My X6 is much louder than my E53 was.  I thought there was something wrong too.

[gs223]

What speed(s) are the problem? My car gets a bit noisy at speeds >50mph, seems to involve some kind of resonance in the cabin. Do a web search for "bmw x3 exhaust boom" and you'll find some links.

[sam82]

[quote="X5Sport"]
Common with all recent X’s in my experience.  BMWs are noisier due to removal of sound deadening and addition of runflats.  My X6 is much louder than my E53 was.  I thought there was something wrong too.
[/quote]

Many thanks for the info

[sam82]

[quote="gs223"]
What speed(s) are the problem? My car gets a bit noisy at speeds >50mph, seems to involve some kind of resonance in the cabin. Do a web search for "bmw x3 exhaust boom" and you'll find some links.
[/quote]

As you mentioned when I hit 50+ it’s feels like I have left my sunroof open. Will try the exhaust boom thanks a lot for the tip

[gs223]

Having done a bit of research, I found links to an outfit called Sound Deadening Shop, https://www.deadening.co.uk/ and made an enquiry, and this was their feedback:

The BMW X3 suffers with body boom as do many modern hatchback type vehicles. We recommend treatment as follows;

A 2 stage treatment. Applying one product and then another product over the top as a 2 stage process:

Stage 1) Treat the metal body panels with Silent Coat 2mm Mat to reduce panel resonance and body boom.
Use on all metal panels up to 50% coverage for most cost effective results, or 100% for a fully comprehensive job. The Silent Coat 2mm product can be used on any metal panel in your vehicle, with the most common areas to treat being the floor, doors, wheel arches and bulkhead.
Concentrate initially on the rear floor and wheelarches of the vehicle as this is where most noise is generated. Car manufacturers apply little if any noise damping material in this area.

Front and rear inc. doors. Recommended pack: http://www.deadening.co.uk/products/sil ... dening-mat

Boot only recommended pack: https://www.deadening.co.uk/products/si ... olume-pack

Stage 2) Use these products straight over the 2mm you have just applied. These tackle airborne noise that is not directly generated by the body panels.

Floor & Boot; Use Dodo Pro Barrier MLV, this is a barrier treatment to block unwanted noise intrusion into the cabin from outside. 100% coverage is recommended for the affected boot/floor areas. Use this product to treat the boot and cabin floor to help block road, exhaust noise and tyre roar.

http://www.deadening.co.uk/products/dod ... arrier-mlv

Doors, sides & roof; Use Silent Coat Isolator Closed Cell Foam, this is a closed cell foam treatment for vertical areas (doors&sides) and the roof. Silent Coat Isolator is a special formulation closed cell foam with excellent thermal and acoustic properties ideal to reduce noise, insulate the vehicle and to isolate barriers and trim panels. (It can also be used on the floor as a substitute for the Pro Barrier if budget is a concern.)

http://www.deadening.co.uk/products/sil ... arge-sheet

For these stage 2 products we'd recommend having a measure up to determine the correct amount needed. We suggest applying stage 2 products like a blanket, covering 100% of the panel.

If I take this on, I'll post again.

[gs223]

One useful post: http://x3.xbimmers.com/forums/showthread.php?t=1316217

[moggyboy]

I spent £320 with a sound deadening company, quite possibly the one your quoting and it made no noticeable difference. I measured decibels before and after, no change.
Save your money.

[Pinewood]

I found changing from run flats to normal tyres made a HUGE difference. I no longer notice road noise.