How I Easily Eliminated Interior Rattles/Buzzing Sounds!

I was hearing a very annoying buzzing/rattling sound coming from the rear trunk/liftback area of my Gen. III any time I would drive without the radio on. But I could not figure out exactly what was causing it.

I decided to put rubber treatment on the rear liftback seal as well as all rubber stoppers around it in the liftback itself as well as in the channel where it meets the body of the car. I also treated all of the 4 side door rubber seals as well as the sunroof rubber seal.

What do you know? This did the trick! I can now drive my Prius without going nuts. It's nearly silent!

I used a product called 303 Protectant just because that's what I had lying around and it's pretty good stuff for rubber. However, I think there is specific car door and window rubber seal products that probably last longer. I plan on re-doing this about every 6 months, only take 10 minutes. I'd also recommend you check your rear 3rd brake light lens to make sure that's screwed in tight (phillips screwdriver required) as well as your license plate.

Also note that if you have a drink in your cup holders while driving, that can cause a buzzing sound.