Cabin noise: road noise or vibration?

My Prius is the quietest car I've ever owned. If you think it is noisy, start by doing a 4 wheel alignment. Mine went bad and the car got noisy. After a 4 wheel alignment, it was quiet again. Same thing in the Matrix I owned before the Prius. Doing an alignment made a huge difference in road noise.

 

heard a metal rattling sound, sounds like it was coming from the front steering wheel, heard the sound when i went over a bump on the road, anyone had this ?

 

This car is definitely NOT quiet. Don't you hear the little engine screaming when you have to pick it up to freeway speed? Rattles will never go away in this car I'm sorry to say, especially since it annoys the heck out of me. But I've come to realize that this car has some of the cheapest and hardest plastics on earth inside it and obviously Toyota didn't spend money on the interior, only the powertrain, which I love btw. I call it my lil rattler.

The Matrix is even louder! A friend had a late model one, and it was loud. Not much insulation and very weak pick up, but overall efficient and good utility with the hatch.

 

I went online to Amazon and bought a couple rolls of Dynomat. Also make certain you have a good pair of heavy sissors and a door panel tool. Simply remove the two small screws holding each front and rear door (one is hidden by a small plastic cover that can be removed with a very small blade screw driver), gently peel down the plastic cover making certain to keep the black tar sealant in place, trace all the open metal door panels to a heavy piece of construction paper and transfer to the Dynomat. Put it in place and begin to peal the cover paper away a little at a time.

It takes about an hour per door to do it right. Go to the trunk and do the same under the spare tire. I also did this under the hood.

The doors now close with a "thunk" like a high end Lexus and the car is much, much quieter at all speeds. The cost and effort is well worth the excellent results.

 

Definitely both, but the annoying sounds are the vibrations / rattles...oh Toyota...

 

I have eliminated most of the squeaks and creeks from the console bridge by wrapping the guide tabs/snaps with Teflon plumbing tape. There are three separate covers on the bridge: radio, shift handle panel and cup holder. All three of these panels have guide snaps that align these ccomponents with the main housing. By wrapping these tabs with Teflon tape I have substantially quieted the interior from these annoying squeaks. Aaaaaaahhhhhhh.