This applies to any year Toyota Prius between 2004-2009 otherwise known as the gen II(2) Prius. If you have a 2004, 05, 06, 07, 08 or 09 Prius and it is making a rattling brake noise over bumps (the little bumps in the middle of the road make it happen especially loud) then this how to fix article will likely help you out.
On my 2005 Prius, I had just replaced the front brakes with brand new pads and new brake hardware. Having done 100’s of brake jobs before, probably 1000’s, it went easily and I did everything like I normally do. When I started driving the car it took me a couple of weeks to notice I was getting this very metallic rattle over bumps, however, it would go away when I lightly push the brake pedal and hit the bumps. If you can get the noise to go away with slight pressure on the brake pedal then you have usually isolated the problem to the brake pads or the hardware.
What ended up fixing the rattling on my Prius?
It wasn’t the pad fitment, not enough grease, or because I used aftermarket pads. It was because of the aftermarket brake hardware that fits into the caliper bracket (the shiny metal pieces that help keep pads secure). I had replaced the ones in the car with the ones I got with my aftermarket brake pads. The new ones did not fit secure and were rattling around when I would hit bumps.
The Fix For 2004-2009 Prius Front Brake Rattle Over Bumps:
There are a couple of ways to go about fixing the annoying rattle. The cheap way or the expensive but better way. The best way to fix it would be to go to buy OEM hardware and pads from Toyota. Because these are generally very expensive and probably one of the most “marked up” items on a car, I tend to avoid buying brake pads from OEM dealerships.
I do stress however that if you don’t want to buy OEM be prepared to waste a decent amount of time in your life chasing brake noises, reduced performance, bad rotors, etc., while you plow through the masses of junk brake parts.
To fix the noise you are going to need to take apart the brakes again. And make sure that the brake hardware is fitting SECURELY in the brake caliper housing. You can apply grease between the hardware and the brake caliper bracket which helps with noise, as well as bend ears on the hardware that helps it stay in place.
I used needle nose pliers and made sure the brake hardware sat firmly in the brake caliper with no brake pads in place. You can also test out your fix by placing your brake pads back in the hardware on the caliper and trying to push them up and down and seeing if you can hear them make noise.
My Favorite YouTuber for Brake Install Good Practice Tips:
Ideally, buy some OEM Toyota front brakes for your 2004-2009 Prius and with the OEM hardware when you install it correctly you will likely not have to deal with this problem. That link goes to Amazon to a search for front brakes for a 2004-2009 Prius– from there look for OEM Toyota parts.
I also find eBay is a great source for OEM parts for less. You can also call your local parts department at your local Toyota Dealership and negotiate with them on the price for brake pads. Typically they will immediately drop the price at least 10% just by asking, sometimes much more if you pressure them or have bought a decent number of new cars from them.
It took me a while to figure out what was causing this noise on my Prius. I hope this article helps you save some time diagnosing the problem on your 2004-2009 Prius. All of these tips also apply to other cars with brake rattle, and the anti-rattle clips are always a great place to start with diagnosis.
Also, as a general rule of thumb, I stay away from parts store brakes unless they are Napa brand for my daily drivers. Otherwise, I am looking for well-known brands for brake pads like Akebono, OEM dealers, or higher performance pads like EBC, etc. I have bought many pairs of $15 rotors on Amazon and $12 brake pads on eBay to install on my own vehicles for the humor of it, and it isn’t funny at all when your rotors warp two days later and your brake pads stop working once you drive a little more spirited than normal.
Also, you don’t need fancy tools to do your own brake jobs. Just make sure you are using a high-quality floor jack and good jack stands. You can check out my complete beginner mechanic tool guide here complete with links to the best priced and highly recommended tools on Amazon.
If I had to choose one aftermarket brand on Amazon for 2004-2009 Prius Front Brake pads it would be these on Amazon. Note: these do not come with new brake hardware. If you live in a non-rust state and your brake hardware isn’t rusty you can absolutely reuse it after cleaning! Otherwise, buy new brake hardware on eBay here.