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Do I need to change my rotors?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Roll Eyes, Nov 21, 2022.

  1. Roll Eyes

    Roll Eyes Junior Member

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    Hello all:

    I have just registered myself on this forum. 4 months ago, my 2005 Toyota Prius (2nd Gen) started making squeaking noise when braking and also while the car was moving (i.e., driving) on the street. I park my Prius on the street. When the Prius started making squeaking noise 4 months ago, I parked the Prius on the street and stopped driving it. I thought I need to change brake pads and probably rotors as well. I was busy with other things going on in my life and did not get a chance to replace brake pads and rotors on the Prius. I am driving another car that I own for the moment. Now with the Thanksgiving and Christmas holidays around, I have to time to replace the brake pads and rotors. Since the Prius was parked on the street for 4 months and was not driven, there is rust on the rotors.

    I would appreciate if you could take a look at the attached pictures of the rotors and give me your take or advice if my Prius rotors are bad and if I need to replace the rotors, along with the brake pads. The first 4 pictures are from the front passenger side rotor and the last 4 pictures are from the front driver side rotor. The Prius has 205K miles on it. Thank you in advance for your time for reading my post and any advice you may provide.
    IMG_20221121_140318.jpg IMG_20221121_140318.jpg IMG_20221121_140332.jpg IMG_20221121_140418.jpg IMG_20221121_140448.jpg IMG_20221121_140547.jpg IMG_20221121_140611.jpg IMG_20221121_140619.jpg IMG_20221121_140809.jpg
     
  2. Mendel Leisk

    Mendel Leisk Senior Member

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    Hard to judge from the pictures, but the pads look pretty low. The rotors do look bad, but nevertheless the rust looks uniform, maybe just “surface rust”, the consequence of protracted street parking.

    Try driving it for a bit; they might clean up. They’ll definitely protest at the start, take a step on the gas to break loose (hopefully). Then they will sound like hell for the first few blocks.

    Continue to drive for a few weeks and they may well just clear up. Don’t neglect the pads though; check the remaining thickness. Almost necessity to at least remove wheels for this. Service limit is 1 mm, but I’d get them changed if they’re 3 mm or less.
     

    Attached Files:

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  3. alftoy

    alftoy Senior Member

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  4. Tombukt2

    Tombukt2 Senior Member

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    Do you want to change your brake pads and rotors? Then go ahead and do so If you don't drive the car stomp on the brakes a bunch of times and see if that mess cleans up on a regular car it'll clean right up pretty quickly but you have to be applying the brakes in In the Prius you're not applying the brakes until the pedal's pretty smartly down they're using electric motors to stop your car mostly. So just give it a go see what you got you can also look into your rotors differently especially once they clean up and you can see your pad thickness is better you just have to look through the wheels and give it a go you'll figure it out kind of hard to explain but the pads are just two pieces of metal with material glued or bonded to those plates squeezing in between the rusty thing you're trying to clean with the pads You're looking for a quarter inch or so or better.
     
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  5. MCCOHENS

    MCCOHENS Member

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    On the outer edge of the rotor there is a blackish line where the rust looks different. This is where the brake pad is not touching the rotor. As the rotor wears there is a noticeable difference in thickness. It is a little tough to tell, because the rust on the outer edge is a lot thicker. But if you can feel the rotor where the brake pads touch is more than a millimeter or 2 thinner replace them. There is a spec for the thickness but it takes some precision measuring stuff you may not have. For reference my truck has worn the braking surface to the point that it is about 3 credit card thicknesses less than the outer part. It is getting new rotors.
     
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  6. Mendel Leisk

    Mendel Leisk Senior Member

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    Specifically, a 0-25 mm micrometer (for thickness) and a dial gauge with magnetic base (for runout (aka wobble). For the micrometer I'd get non-digital, simpler, cheaper, and no batteries to burn out. Not sure if there's such a think as a digital dial gauge, but I'd avoid those as well, if they exist. Both instruments are $25~50 on Amazon. The spec's for rotors are in post #3 attachment.

    That said, I suspect they're ok, and with a bit of driving and they'll clear up, no issues. It will be noisy at first though...
     
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  7. SFO

    SFO Senior Member

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    First confirm that the brakes still work, then get it up to a safe speed, shift into neutral, and gently apply the brake pedal. Rinse and repeat.
     
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  8. Roll Eyes

    Roll Eyes Junior Member

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    Thank you for your reply. Actually, I have checked ROCKAUTO over the weekend and was leaning towards purchasing one of the three brake pads and rotors kits with the red heart sign next to them. Are you referring to the last kit, "POWER STOP CRK5219 Evolution Geomet Coated Kit" that is priced at $80.79, currently?" Are the 4 things at the bottom of the picture on the last kit the caliper slide pins? Or do I have to buy the caliper slide pins, separately? I am sorry, if I sound stupid. I am totally new to the Prius maintenance subject. I am trying to educate myself.

    By the way, I have read some posts on this forum from other forum members who complained that when they replaced the OEM brake pads and rotors with cheap non-OEM brake pads and rotors, they lasted only for a few months and they were not as good as OEM ones, and they had to replace them again with the Toyota brand OEM brake pads and rotors. That is the reason why I wanted to keep these OEM rotors as long as I can, even though they look rusty. It may sound funny, I am also looking at the option of removing the existing rusty rotors from the Prius and remove the rust by soaking them in a rust removal liquid, or with white vinegar, or baking soda, and (if they look good) put them back on to the car.

    Also, I spoke to a car mechanic over the phone last week (the mechanic did not inspect the car yet), and the car mechanic suggested that I get the brake pads that come with a lifetime warranty from Auto Zone, who will give a free replacement of brake pads after they wear out 3 or 4 years down the line. I am doing my own research though as to the best course of action I need to take.

    If I do not need to change my brake pads and rotors, then I do not want to. Thank you for your reply.

    Thank you for your reply.

    I have seen a youtube video, where the video uploader suggested to put a finger on the center/surface of the rotor, press the finger against the rotor, drag the finger towards the outer edge of the rotor, and feel for a lip on the outer edge of the rotor. If you feel there is a significant lip on the outer edge of the rotor, it means the rotor is becoming thin, and it needs to be replaced.

    I do not know, if I am correct, but from the pictures I posted in this thread, my rusty rotors do not appear to have a significant lip on the outer edge of the rotor. Or it could be that rust is too thick that I do not see a significant lip on the outer edge of the rotor. I thought I would post the pictures of the rotors and get an opinion from the more experienced members of this forum.

    By the way, to my eyes, the braking surface of the rotor do not appear to have worn out by 3 credit cards' thickness in comparison to the outer edge of the rotor.

    What is the goal of your suggestion here? If brakes are working, are you suggesting this process to clear the rust off the surface of the rotor? Thank you for your reply.
     
  9. Roll Eyes

    Roll Eyes Junior Member

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    Thank you for your replies, Sir. Before I registered myself here and posted this thread on this forum yesterday, I have tried to research the issues on my own and have read some of your posts on this forum. You come across as someone with a great knowledge on Priuses & cars.

    From the 3rd picture and the last picture, the brake pads appear to have 3mm or more in width. In any case, I will either remove the tires myself and check the brake pads or have them checked by a car mechanic. From your and other members' replies above, the squeaking noise is due to the worn out brake pads, which probably need to be replaced, but the rotors appear to be fine and probably do not need replacement at the moment (of course, I will follow the suggestions to see if I can clear off the surface rust off the rotors). Is my assumption correct?

    FYI, I had purchased this 2005 Prius, used car, from the prior owner (who purchased from another prior owner) in 2019 when it had 190K miles on it, so I do not know anything about this Prius's maintenance history, or if these rotors and brake pads came with the new car back in 2005, or if one of the prior owners replaced the rotors and brake pads on this Prius.
     
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  10. Tombukt2

    Tombukt2 Senior Member

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    I 9mag9 ex you stomped them clear maybe last night ? So how they look. Now??
     
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  11. Roll Eyes

    Roll Eyes Junior Member

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    Just changed the brake pads with Duralast ceramic brake pads (cost including tax was $36.37 and came with a lifetime warranty) from Autozone by myself. Kept the same rotors. This is my first time doing the brake job by myself. It took a little over an hour on both sides in the front, and it wasn't difficult. The squeaking noise is gone now. Attached are pictures of the old brake pads that I replaced. Saved some $$$.

    IMG_20221130_185541.jpg
     
  12. dolj

    dolj Senior Member

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    Yeah, that pad on the left has no friction material on it–it is right down the metal. You found the cause of your squeaks.

    I'd be surprised if you didn't also damage the side of the rotor where that pad was located.
     
  13. Roll Eyes

    Roll Eyes Junior Member

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    No damage. I was prepared to replace rotors along with the brake pads, but I felt the rotors were fine. The rust on the rotors in the pictures in the OP is just surface rust. I felt that the rotors will last for another 50K miles, at minimum.

    The ride I heard the squeak was the last ride. A few years ago, I kept driving my Toyota Corolla, despite the squeaky noise, and the continued driving screwed my brake piston caliper. I had to spend some additional money to replace the brake piston caliper along with the brake pads and rotors. I learnt my lesson. This time, I stopped driving immediately after I heard the squeak in order to prevent further damage to other components.
     
  14. justlee

    justlee Junior Member

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    Your new pads will seat in fast with all that rust and that is a good thing! Did you replace or lube the pins so that you know the caliper can move to center itself and apply pressure to both sides of the rotor? I ask because only the pads on one side have rust dust on them. Maybe the piston side? Couldn't hurt to remove wheels and look at the brakes after a few thousand miles to see how things settled in. Both sides should wear about the same but the piston side pads usually wear a little faster because they get pushed against the rotor a little harder due to friction at the mounting pins. I almost never change rotors unless they are warped or have hard spots.
     
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  15. dolj

    dolj Senior Member

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    That's good to hear. I was thinking, "a stictch in time ...", and I see you're on to it. Good work!
     
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  16. Tombukt2

    Tombukt2 Senior Member

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    Rotors are so 8nexpensive these days as are pins and clips . Usually do all including struts and end links too . Just less things to do later . And all that's almost off anyway
     
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  17. ChapmanF

    ChapmanF Senior Member

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    Here's what's weird to me in that picture: on one pad of each pair, there's supposed to be a little spring clip with an end that bends around and points toward the rotor. It sticks about a millimeter past the metal backing of the pad. Its whole job is to make a shrill squeaking noise as soon as the pad is worn down to that last mm, so you know it is worn, well before the pad is all gone and the metal is touching the rotor.

    I don't see that clip on any of those pads. Were they there and you pulled them off before taking the photo? Or were these already some aftermarket pad that didn't have them?
     
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  18. Mendel Leisk

    Mendel Leisk Senior Member

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    I was thinking the left end pad was upside down??
     
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  19. Roll Eyes

    Roll Eyes Junior Member

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    I lubed the existing pins. I did not buy new pins and replace the pins.

    Yes, you don't need to replace rotors or anything in life, unless the replacement is necessity. It is a waste of resources; natural, monetary, and other.

    Thank you for your advice.

    Could be inexpensive, but is the replacement necessary? I do not want to make this planet Earth more dirty by throwing away perfectly usable things somewhere in the corner.

    The clips were there, but I just didn't take the picture of the clips. I just wanted to show you all and others the wear and tear on the old brake pads who might come here for help in the future with a similar problem.

    Possible. I am inexperienced person in these sort of things. The top of the brake pads as it shows in the picture were touching the surface of the rotors and that's where the brake pads were worn.

    Thank you all for your time and advice, which for sure helped me to make an informed decision and confidence in doing what I have done, and also helped me to save some money.
     
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  20. Tombukt2

    Tombukt2 Senior Member

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    Some people break those squeal inducers off .