Make my Prius QUIETER

I was thinking that spraying the wheel wells with Rhino Bed liner coating might not be a bad idea. I wouldn't use a spray can but have it done in a shop that specializes in bed liners.

 

I have done this, a slight improvement in road noise. I have also under coated the body with it, took off the under body panels. Sight improvement.

 

dynamat and the like. do under the carpeting, inside the doors and the hatch under the tyre. buy new tyres and spray the wheel wells. you'll have yourself a rolls royce.

 

There is no easy solution. Mass loaded vinyl married with closed cell foam is the only truly effective sound blocker that I know will work in vehicle application. Although there is some closed cell foam used in aircraft for heat and sound blocking that is somewhat effective.

A little dynamat goes a long way to deaden reverberating body panels but it is not a sound blocker. Lining your car with something like dynamat only makes your car heavier and the dynamat guys richer.
Lots of good info here: Sound Deadener Showdown | Your Vehicle Quiet

 

Maybe good tires? Michelin MXM4s might do the trick?

 

Ear plugs... J/K

 

I know that this stuff works in industrial settings. Not sure how you'd get it retail, though:

Mascoat Sound Control-dB

 

I too am interested in making my Prius quieter as my commute to work often requires me to take highways / interstates when the surface level streets are clogged. Has anyone ever taken detailed measurements to narrow down the origin of the noise and how sound deadening material helps quiet things down?

 

I purchased a set of Dunlop sp blue response by far the quietest tyre I have had now concrete M50 is bearable we don't Need to turn the stereo up to drown the noise

 

See post # 4 from Bisco.

That is the answer.
Biggest of the list would be to remove the seats and carpet and line the floor with Dynomat.
Yet that will quiet the car.

Have fun.

 

Except, Dynamat isn't a good noise blocker--it's a vibration damping mat that stops panel resonance. To block noise, you need mass, and the most effective way to do that is with heavy, mass-loaded vinyl over a decoupler, usually closed-cell foam.