How-To soundproof your Mazda5

But it's these freakin' tires! This car EATS tires! My stockers one my 06 get loud after 5K miles and these Pirelli 18 inchers I have on my 07 do the same thing. I guess it's a good "reminder" for me to rotate. But I've noticed that even with rotation, once they start to make noise they always make noise. No matter which tire!

I have heard others complain of this but I just picked up the car a week ago so I cannot comment. But I wonder if it's a common alignment issue in all of them? Does anyone know the stock camber, caster, and toe specs in front and rear? I have noticed on the freeway at around 70-80, the car feels a little bit twitchy. Makes me wonder if the stock toe settings are really ideal.

Maybe someone with a lowered 5, that has had custom alignment, could comment as to whether the tire wear and/or noise got better?
 
You are the man!

I have been meaning to add sound insulation to my wife's Mazda5, but I never found enough info and guts to just rip stuff out. Thanks for being the pioneer, and now I can get more answers and possible courage to do it.

I was wondering if you can answer a handful of questions (a couple hands actually) about your installation:

1. Did you break/replace any tabs, hooks, or clips? My wife is quite squimish about me breaking her new ride.

2. Do you have diagrams / pictures on how to remove body panels and seats?

3. I read somewhere that one has to disable to the battery to remove the seats so the airbag wouldn't deploy. Is that so for the 2nd and 3rd row seats?

4. How long did it take for you to remove everything before adding sound insulation material?

5. What tools are needed to remove stuff? Metric socket wrench? Crowbar? Did you use a torque wrench? Did you have to apply thread lock when putting things back together?

6. How much materials did you end up putting in? How thick is the insulation? Did everything fit back in?

7. How did you layout the material? Cover all surfaces except for access holes? Did you cover the cavity from the metal skeleton to exterior surface panels? Did you apply material to the inside of exterior surface panels? Pictures would be great!

8. What is that black hatch with an arrow on it under the second row seats? Escape hatch? Porta-pottie?

9. Did you just fold up the carpet instead of removing it from the vehicle?

10. How much more quiet is the car now? Over the rough road surface, does the car still drone? (BTW, I have done some comparison between 2008 Mazda5 and 2007 BMW 335i sedan, and the difference is ~3 dB. I would describe the difference being ringing vibration vs. thud.) Attached is a picture of the frequency response at 80 mph over same stretch of road.

Any extra pictures will be greatly appreciated. Congrats again on completing the installation, and thanks for any answers that you may provide!

(cool)(yippy)
 

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^^ (wow) What a detail thugus. I have learned a lot on this thread, serious. 3dB difference between a Mazda5 and a 335i? If I tell you the dB I was used to resist at the pub Thu, Fri ad Sat during my junior high and college days, 3dB was peanuts :D...

I'm sold to those numbers you show, love my 2 $18K cars a little bit more now...

Oh, and for the tires, I don't put many miles a year on my cars, but the OEM ones on my 06 (bought in Jul 2005) don't show that they are going away anytime soon!! (headshake
 
In researching sound proofing stuff, I also learned quite a bit. For example, 3 dB is just my estimated weighted average across the frequency spectrum. There is dBA and dBC weighting which you can learn about on wiki. Max variation is actually around 5 dB between BMW and Mazda5, but it didn't cover much of the frequencies. If you go buy a digital sound meter from Radio Shack, it has both dBA and dBc weighting.

For me, I would like to be prepared as much as possible before starting a project. As much fun as it maybe to just dive in, I can't afford the down time and the wrath of my wife when CLEARLY it is my idea and project, not hers.

Unfortunately for me, the car is still brand new, so new tires are out of the question.

Hopefully experts in sound insulation can chime in and give some insight.

^^ (wow) What a detail thugus. I have learned a lot on this thread, serious. 3dB difference between a Mazda5 and a 335i? If I tell you the dB I was used to resist at the pub Thu, Fri ad Sat during my junior high and college days, 3dB was peanuts :D...

I'm sold to those numbers you show, love my 2 $18K cars a little bit more now...

Oh, and for the tires, I don't put many miles a year on my cars, but the OEM ones on my 06 (bought in Jul 2005) don't show that they are going away anytime soon!! (headshake
 
I have been meaning to add sound insulation to my wife's Mazda5, but I never found enough info and guts to just rip stuff out. Thanks for being the pioneer, and now I can get more answers and possible courage to do it.

I was wondering if you can answer a handful of questions (a couple hands actually) about your installation:

1. Did you break/replace any tabs, hooks, or clips? My wife is quite squimish about me breaking her new ride.

2. Do you have diagrams / pictures on how to remove body panels and seats?

3. I read somewhere that one has to disable to the battery to remove the seats so the airbag wouldn't deploy. Is that so for the 2nd and 3rd row seats?

4. How long did it take for you to remove everything before adding sound insulation material?

5. What tools are needed to remove stuff? Metric socket wrench? Crowbar? Did you use a torque wrench? Did you have to apply thread lock when putting things back together?

6. How much materials did you end up putting in? How thick is the insulation? Did everything fit back in?

7. How did you layout the material? Cover all surfaces except for access holes? Did you cover the cavity from the metal skeleton to exterior surface panels? Did you apply material to the inside of exterior surface panels? Pictures would be great!

8. What is that black hatch with an arrow on it under the second row seats? Escape hatch? Porta-pottie?

9. Did you just fold up the carpet instead of removing it from the vehicle?

10. How much more quiet is the car now? Over the rough road surface, does the car still drone? (BTW, I have done some comparison between 2008 Mazda5 and 2007 BMW 335i sedan, and the difference is ~3 dB. I would describe the difference being ringing vibration vs. thud.) Attached is a picture of the frequency response at 80 mph over same stretch of road.

Any extra pictures will be greatly appreciated. Congrats again on completing the installation, and thanks for any answers that you may provide!

(cool)(yippy)

damn dude. I have charted many things, but db level in my car isn't one of them (wiggle)

I would love to see that chart vs some of my previous cars. Had a 2004 WRX STi. The factory doesn't even put most of the sound deadening IN that car, to save weight. The road sings to you. Also had a 98 Integra GSR. I was proud that the factory rated them at 83db during WOT.
 
I want to know if it works!

Ha ha! I wanted to make sure whatever I change actually produces measureable result vs. I-just-spend-3-days-and-$500-so-it-must-be-better delusion. Perhaps we should start a website of just sound recordings and comparison between different models.

BTW, when I was doing the sound measurement, the dominant noise is road noise, followed by wind noise, then almost unperceptable engine noise and exhaust noise for the Mazda5. From what I read, adding sound deadening material and blocking any sound leakage will help the most. I also try to find info on placement of sound deadening materials, and the closest I come to is to add it to where sheet metals come together, so the resonance structure is bigger thus requiring more energy to cause resonance. Does this sound right to everyone?

And no, I haven't even bought materials yet, though I have spent some time thinking about it.

(uhm)


damn dude. I have charted many things, but db level in my car isn't one of them (wiggle)

I would love to see that chart vs some of my previous cars. Had a 2004 WRX STi. The factory doesn't even put most of the sound deadening IN that car, to save weight. The road sings to you. Also had a 98 Integra GSR. I was proud that the factory rated them at 83db during WOT.
 
Thank you for this post! I was wondering what was under all that plastic back there. What kind of insulation did you put in? Was it that mat-type, or something you sprayed/rollered on? And my previous car was a convertible, so the 5 seems like driving a library or something in comparison to me.
 
I was wondering if you can answer a handful of questions (a couple hands actually) about your installation:
I'll do my best. :D
1. Did you break/replace any tabs, hooks, or clips? My wife is quite squimish about me breaking her new ride.
No. Everything pops off quite easily.
2. Do you have diagrams / pictures on how to remove body panels and seats? 4. How long did it take for you to remove everything before adding sound insulation material?
I don't have diagrams but it is so easy I could probably just go do it again and take detailed pics. It only took about 1/2 hour to remove everything from the hatch to the back of the front seats. Both rows only have 4 14mm bolts holding them down. The third row has three of push pins that hold the back of the carpet up to them. The rear panels come out by removing the rear ties downs with a 10mm socket. there are two Phillips screws on the upper back panel and below the third row window are two covers that remove to reveal a 10MM bolt. Actually only the rearmost cover has to be removed on each side. The forward one doesn't have anything underneath it. Go look at your car and you'll see what I'm talking about. :) There are some push pins type thingies...you know...the push pin that has the middle part that comes up so that the whole thing can be removed? ...Anyway...you'll see two when you remove the third row and the rear most trim has a couple.
3. I read somewhere that one has to disable to the battery to remove the seats so the airbag wouldn't deploy. Is that so for the 2nd and 3rd row seats?
No need for the battery disconnect for the 2nd and 3rd row. I will disconnect it to remove the front seats since the airbags are in the seats themselves. 2nd and 3rd row have the curtains in the pillars not the seats
5. What tools are needed to remove stuff? Metric socket wrench? Crowbar? Did you use a torque wrench? Did you have to apply thread lock when putting things back together?
Phillips screwdriver, butter knife for the beauty covers & push pins (always worked best for me), 10mm socket, 14mm socket. No crowbar, no torque wrench. I did use my air ratchet to speed things up and tightened everything down with it too. No thread locker either. The seats just aren't put under the type of vibration that would cause the bolts to come loose.

6. How much materials did you end up putting in? How thick is the insulation? Did everything fit back in?
I used almost one roll of B-quiet Ultimate material. One roll = 50 sq. ft. I have probably 15 sq. ft. left. You can the the specs off their website. In some places it is doubled...like the spare tire well. Meaning: there are two layers. Everything fit back just fine. No issues.

In hindsight, I'd see if someone had material that was not 12" wide. I got all these rolls to sound proof my Excursion some more. I have a lot of the back of it soundproofed because of the aftermarket exhaust on it. 12" wide is great for my truck's large, flat floor and huge mutha doors. But on a small car like this is is a bear to work with sometimes.

I wasn't even thinking about doing the 5 until the night before I was going to do the truck I took my wife out to dinner and drove the 5. I thought..."this thing is louder than the Excursion! I should do this one first."
7. How did you layout the material?
As best I could. It's not an exact science really. I didn't have a planned pattern. I just made things work as best I could using the longest/largest pieces I could manage.
Cover all surfaces except for access holes? Did you cover the cavity from the metal skeleton to exterior surface panels? Did you apply material to the inside of exterior surface panels? Pictures would be great!
Yes, yes, yes..as best as I could reach. Even a smallish piece on the exterior panel can help prevent vibrations and unwanted resonance.

You basically start by tapping an area and if it vibrates continue to add dampening material until it "thuds".

8. What is that black hatch with an arrow on it under the second row seats? Escape hatch? Porta-pottie?
I have no idea. I ran out of time to pull off the cover and see. When I tear it apart again I'll pull it off and take a pic. :)

9. Did you just fold up the carpet instead of removing it from the vehicle?
Yeah, actually the carpet kinda automatically folds in front of the second row. You can see the bottom of it (white) in some of the pics. I basically picked it up and leaned against the front row.

10. How much more quiet is the car now? Over the rough road surface, does the car still drone?
I wish I had my church's decibel meter. I always seem to do mods and never get the baseline in which to compare from. The main part (right now) that is quieter is obviously the third row. A LOT less road noise and it just feels more isolated from the world when you're in the back. On thing though...the rear speakers sound awesome now!

The front is still loud (to me). I can really hear the engine...which isn't a bad thing...but I would like to quiet that down some more. And of course, the tire noise mentioned before. I think doing the floor pan will help a lot with that. The firewall looks like a real PITA. Having the exhaust header right there doesn;t help as far as keeping the noise out of the cabin. But it looks to be very hard to get to. We'll see...it's on my "list" for Wednesday...maybe...hopefully...

I WILL take better pics. Especially when I pull the door panels. I think it would be good to have a pictorial on that alone.
 
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You are awesome!

Thank you so much for answering all the questions! I am gaining more confidence with all your explanations.

On question 7, you answered that you covered the cavity from the skeleton to the exterior body panel. Does that mean there is a patch of sticky stuff that is not in contact with metal, or did you fill the cavity first with wood/ fiberglass/sheet metal first? Please excuse the shameless borrowing of your picture and highlighting the area of interest.

Thanks again for all the info!

(bowdown)
 

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I didn't fill that cavity with anything. I did put material on the sheet panel through the holes and then covered all the holes and in some cases doubled the material layers. Those 3 or 4 holes on the upper portion are now sealed. I think that helps the speaker and "pushes" the sound from it out instead of letting it go behind it and get all washed out.

If anyone is interested...that wire going across the floor is the fuel filler door release cable.
 
Thanks for the clarification. I think I may have said it incorrectly about 'fill the cavity'. What I meant to say was 'fill the opening hole to the cavity'. From what you have mentioned, you do cover the holes with the material, such that the cavity is complete enclosed. I have read elsewhere that people actually apply a layer of something to add support for the material over the opening of cavity.

For example, this is what I understand about your setup:

car interior -> material* -> opening hole to the cavity -> cavity -> material* -> inside of exterior body panel

vs. what I have read elsewhere:

car interior -> material* -> fiberglass / metal plate (same size as the opening hole)* -> opening hole to the cavity -> cavity -> material* -> inside of exterior body panel

where '*' means glued/stuck to the item after the arrow.

My main concern is that without backing plate over the cavity hole, the material will eventually become unglue and peel. I would rather not have to clean up a peeling mess after a hot summer.

I can't wait to sit in the 3rd row and actually hear a conversation in the 1st row!



I didn't fill that cavity with anything. I did put material on the sheet panel through the holes and then covered all the holes and in some cases doubled the material layers. Those 3 or 4 holes on the upper portion are now sealed. I think that helps the speaker and "pushes" the sound from it out instead of letting it go behind it and get all washed out.

If anyone is interested...that wire going across the floor is the fuel filler door release cable.
 
Isolating the back wave of any speaker from the front of the speaker actually makes the bass "work". Otherwise it's not very effective at all. Should sound much better!

I think I have a project. How much is this stuff? It's been a long time since I have purchased any.
 
Any more updates from monsta?

I am eagerly awaiting pics from your next sound proofing session. Show us your mad skill!

(bowdown)
 
Sorry...been busy moddin' my Excursion...

I'm gonna take the interior out of my 5 again in a few days and I'll get detailed pics.
 
oem soundproof

Does all the Mazda5 models from 2006 to 2008 have soundproof? If not, which ones have it? I'm planning to purchase either 2007 or 2008 Mazda5, at least a touring package.
 
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Should be the same sound insulation.

There should be no difference between 2007 and 2008 in regards to sound insulation. It is no $60k luxury cruiser, but neither is it a stripped track car. I would say it is on par with Honda Civic in terms of noise.

The major differences for 2008 model are the rear air condition vents and 5 speed auto gearbox. It may or may not justify the price difference for you.

Good luck!

Does all the Mazda5 models from 2006 to 2008 have soundproof? If not, which ones have it? I'm planning to purchase either 2007 or 2008 Mazda5, at least a touring package.
 
Thought I would resurrect this thread, and ask the OP, Monsta, a question. In your pics of the interior, I can see where the carpet folds up behind the front seats. It appears the underside of the carpet is molded to a very specific shape to fit the underlying surface. Based on what you've seen, is it possible to lay down a sound barrier that is "too thick", or if it's a barrier that is not as formable as one of the damping sheets (like fatmat): would this interfere with the carpet's ability to lay down properly?
 
Thought I would resurrect this thread, and ask the OP, Monsta, a question. In your pics of the interior, I can see where the carpet folds up behind the front seats. It appears the underside of the carpet is molded to a very specific shape to fit the underlying surface. Based on what you've seen, is it possible to lay down a sound barrier that is "too thick", or if it's a barrier that is not as formable as one of the damping sheets (like fatmat): would this interfere with the carpet's ability to lay down properly?

I would say, YES, but it would have to be pretty thick. Using the self adhesive sound deadening mat won't interfere. Some of the areas I did even have two "coats" with no isuues with carpet fitment. So I guess it really depends on what type you use.
 
Hey Monsta, thank you for the reply! You and a couple of others have asked me what I'm looking at for sound barrier. When you take a look at this stuff, you might have some additional thoughts about how well it will fit underneath the carpet. I think the problem (if there is one) will be that it doesn't form around the nooks the way a damping material does.

There's a thing called MLV, which stands for Mass Loaded Vinyl. It's a very dense substrate that is used in things such as home theater applications. It's sold in at least a couple of auto sound places that I've found on the net, but the interesting thing is that it's entirely possible to buy it directly from other sources, and probably save money.

Anyway, the best thing about MLV, from a barrier perspective, is that it really does appear to be the real deal. I've found sites that list its sound barrier properties, and MLV's properties measure up very well with what I consider to be the gold standard, Cascade Audio VB-3/4. MLV is not quite as good as VB-3, but it basically sits on the capabilities of VB-4.

There's more to a sound barrier application than just MLV, but it's the primary component. For more, this web site contains good info: http://www.sounddeadenershowdown.com/cgi-bin/index.cgi

I will probably wait until cooler weather, and I still want to think about it some more, but that's where my thoughts are right now.
 
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