Prius sound proofing

I'd be interested in how you do this as I'd sacrifice some MPGs for better sound-proofing too. Some here have suggested starting with the wheel wells. Maybe putting foam rubber behind the front wells to prevent sound-transfer from the road into the body. Also, how about some foam rubber along the firewall? The door panels can be easily removed and you could add foam or other sound-proofing material inside them.

When I had my dash plate out about a year ago, I should have considered putting foam rubber as far down the inner fire-wall to mitigate noise transfer from the engine compartment.

 

Yes, there have been some folks who went the dyna-mat route so search. I've been kicking the idea around but if I do it will be with much less costly carpet padding and added to easier to get spots (lower hatch, front foot wells) first. Next will be replacing the stock tires when they wear out with something quieter; possibly continental ecotec's.

 

Search Dynamat - many here have done it - it makes sense to do when you swap the door speakers.

Sonically it helps a bit (not a lot - but it is noticeable) - I think the biggest improvement is the door/skin 'feel/sound'. Much more like a Lexus door closing (thud).

I don't think carpet foam will do much - but there are makers of knock off Dynamat that should be fine...

I did doors, under rear seats, back side panels, below tire etc. Tap on the outside skin of the car, and it sounds solid.

Did it make much of a difference with my premium sound system - not really.........................

 

i am thinking of spraying foam insulation in all the cracks and crevices. that seems to be where most of the noise is coming from.

 

Outside of the possible toxic effects, I'd be worried about it trapping any moisture and accellerating rusting...

 

hmm, hadn't thought of that. maybe if i did it when the weather is really dry. i don't think it's toxic, you use it for home insulation.

 

Personally, I think most of the noise issues can be corrected with different tires. My Michelin Energy Saver tires have rendered noise a non-issue.

 

I doubt it's the tires. I know when I drive mine it sounds like a window is slightly cracked, but of course none are open.




iPad ?

 

I do not recall the OEM tires, but I seem to recall they were Yokohama's. I now have Michlin Energy Saver A/S. I have read they are not too good in snow, but I have a second vehicle for those situations. I am very pleased how queit they are ... and LRR too.

Unfortunately, I read elsewhere that they are hard to find now.

 

Regarding noise levels in the Prius gen 3, when I bought my 2010 the interior noise was so bad that you could not carry on a conversation above 45 mph. I might not have known the cure except that I had exactly the same problem with my 93 Camry which I just got rid of (nearly 20 years of trouble free operation). I bought new tires for the Camry from Tire Rack after reading their very detailed tests and thought I was driving a new car. Same thing this time. Original tires were Bridgestone Ecopia ep20, all season, optimized for low rolling resistance, ie high mileage. I bought new rims (used toyota) and Bridgestone Ecopia ep100, a summer tire. Same result, talk at normal levels at 70mph and enjoyable driving for the first time. I put the all season back on in the winter.

 

So the new tires you bought for the Camry that were quiet and cured the noise were the Ecopia ep20?

 

i think he was saying the prius came with the ep20's and he changed to the ep100's.

 

Dynamat won't block road noise. Dampening metal vibration is only the first step to sound deadening. To block the exterior sound, in addition to a layer of Dynamat, you will need a layer of closed cell foam and then a third layer of Mass Loaded Vinyl. The closed cell foam creates an air barrier by decoupling the MLV. The MLV, which has a mass of 1lbs per square foot, does all of the sound blocking. For the doors you could add a fourth layer of 3M Thinsulate.

After my sound deadening project, I lost a couple MPG with an extra 100lbs of weight. I can live with that. I've done this to the entire floor and all four doors of my 08. The last step will be the firewall and rear hatch door.

 

Dynamat helps, but I agree it's not the total answer. I did it a few weeks ago and it has dampened most of the road noise.
I still think adding more dampening to the wheel wells will help too:
Dynamat 2.0 | PriusChat

 

Carpet padding is the answer for floor and firewall noise...That is what lexus uses...has been used for decades in the upper end cars..

 

I've owned two Prius, 04 and our 10 and the cabin noise is my biggest complaint. I wonder where I would start to find a RELIABLE shop to do this work for me. I would hate to go thru all of this and end up with a car full of rattles, any ideas?

 

I was hoping someone would mention the type of foam( and where to get it) one uses to seal the doors, a layer (1"x 1/2")? applied correctly would stop all the dirt and water from entering(I always have dirt after it rains coming up from the sills), I'd think the noise would also go away
Dynamat on the inner door panels will change the vibration frequency, changing the sound, it'll be a lower frequency, some of it will be there but it "works". Everything vibrates, (metal echos more then carpet and sound deaden-er), dynamat absorbs vibration lowering the frequency of vibration, and the sound level.