How to: Cheaply STOP/Lessen Your Prius C Trunk Rattles!

Hello Priuschat!

I recently installed a 10" Alpine Type R Subwoofer (Installed Alpine Type R 10" Subwoofer! | PriusChat), but the trunk rattles were annoying and made listening to music less satisfying. I was able to completely remove mine with only FELT pads intended for chairs. Note that i went for sound quality, not overpowering bass on my setup. I am only pushing 20% of the subwoofers' capabilities.

First, you have to keep your rear liscence plate from rattling. In order to do this, apply 3 or 5 Felt Pads to the back of the licence plate. One near the top right, one in the top left, one in the top middle. This was sufficient for me.



Second, have a look at the inside of the trunk door/lid. You will see a black automotive carpet type pad attached to the inside of the lid. On the inside of this carpet, its hard plastic, and this was the other main source of my rattles. You will see that it is fastened by plastic pins that are secured. Don't take these out. Instead, kind of pry the carpet piece so that you can fit a felt pad onto the top of the carpet piece on the inside.

Awesome tip! I just bought a bunch of those felt pads to put on the bottom of my house furniture, I am definitely going to give this a try.

My C came with rubber pads behind the license plate. Good tips though. Thanks.

Its definitely a lot cheaper than products like dynamat. And in my opinion its better because its less work and just as effective.

Thanks! I thought it was the jack handle parts and have repacked it and rewedged it under the spare. Then I wedged the license plate, better not repaired. Now the pad.... Thank you.

There is simply no accounting for musical taste, is there? (the videos)

I immediately needed a dose of Bach. Here's a rare clip of Glenn Gould 'practicing'

Haha i wasn't showcasing my musical taste, i was showcasing the sound system. I honestly hate those commercialized rapper songs, but they do have great bass.

OK. Try converting the audio of this to mp3; give it a whirl on your new alpine and let me know what you think. Playing the Bach cello suites on a bass significantly increases the difficulty, by the way. The bass on my laptop seriously sucks.

I was fed up with my license plate rattling and bought two well nuts (nuts with rubber feet) and two machine screws and screwed them into the bottom license plate holes. I did this for under two dollars. Dunno how costly felt pads are but the nut+screw is guaranteed to last longer w/out adhesive or fabric degradation issues

That sounds like a good idea too. I think i might do the same to mine when i get the chance. It will certainly last longer than my felt pads haha. Thanks for sharing.

Can you post a picture of the well nuts please? Those will be my next attempt. My rear plate rattle has improved but not eliminated.

I don't have any of the rattling noise discussed on this thread, but would recommend 3m double sided tape under the license plate, just stack one small strip on top of another until you get the thickness you need to eliminate the contact causing the rattle. Easy to apply and unseen under the plate. Hope this helps.

Amazon.com: well nuts: Industrial & Scientific

Thanks for the tip! In my case, i had rattling because of excessive BASS. hahaha. you shouldnt have any unless you have a subwoofer,

I open and close the hatch 30 - 50 times a day. It used to rattle each closing - annoyed me. I drilled a couple of new holes for the bottom, put a sheet of closed cell foam behind it and bolted it down. This was the hard way to do it which involved taking off the hatch liner (not difficult with a plastic wedge to pop the fasteners) but finger/hand contortions to thread the bolts. But. it. doesn't. rattle. at. all.

Does your C3 have a hatch liner on the inside?

Does your C3 have a hatch liner on the inside?

Hatch liner? Can you describe what you mean by a hatch liner? I do have the privacy lid that drops down so that you can't see what is in the cargo hold or trunk area...

At the top of this thread, Daze's 3rd pic down and he calls it "black automotive carpet type pad attached to the inside of the lid.".

This is what I,m referring to as a hatch liner.