2016 Prius Two Eco - rear brakes, what am I doing wrong

Discussion in 'Gen 4 Prius Care, Maintenance and Troubleshooting' started by King_V, Apr 17, 2026 at 2:17 PM.

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  1. King_V

    King_V Junior Member

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    2016 Prius
    Model:
    Two Eco
    So, I did do a bit of digging first, but I'm wondering if I'm doing something wrong. I've done more than my share of disc brake replacements in the past, and even last year. Never did it on a Prius or any hybrid though.

    I've got about 80k miles on my Prius, and I was told that the rear brakes are very low. Of course, the dealer would love to do it, and insists that the rotors also need to be changed. I can only imagine what they'll charge. I figured I might at least attempt to inspect it myself.

    I am aware of the weird cross-like thing that I'll have to rotate back in if I put new pads on, but at this point, I'm just looking to inspect, and see if I can get the caliper off.

    This is what I did:
    1. Opened car with fob, and opened hood
    2. Disconnected negative terminal of battery
    3. Loosened lugs
    4. Jacked up car
    5. Removed lugs and tire
    6. Realized I couldn't even turn the hub, thus went back and released the parking brake (it's a mechanical one)
    7. Now could turn the hub via hand on the studs, but there's some resistance
    8. Removed caliper bolts
    This is where it gets weird. I completely removed the top bolt, but left the lower on, but very loose (could easily turn with fingers), figuring I could just pivot the caliper without fully removing it.

    The caliper would barely budge. Couldn't do anything with hand, and using large flat-head screwdriver as a pry, I maybe got it to move a hair, at best.

    Are there any extra steps I've missed? I'd really like to give it a try again this weekend, probably on Sunday.


    As a side note - for that part on the caliper that I have to rotate back in, will a typical needle-nose be strong enough to do it, or should I get a particularly heavy duty one because it needs a lot of force? I've read in a few places that the specific tool to rotate it back into place is awkward.

    EDIT: while I'm on this, are the typical semi-metallic pads the norm on a 4th gen Prius, or do I need to get something different?
     
    #1 King_V, Apr 17, 2026 at 2:17 PM
    Last edited: Apr 17, 2026 at 3:09 PM
  2. rjparker

    rjparker Tu Humilde Sirviente

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    this should work
     
    #2 rjparker, Apr 17, 2026 at 2:27 PM
  3. King_V

    King_V Junior Member

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    Two Eco
    That looks straightforward enough, but it's the rear brakes I'm working with, and there's some extra considerations like the rotating piston retraction, the car possibly attempting to push the rear brakes even when off (hence why I assume the battery disconnect is required), and so on.

    Just wondering if I had missed something in my steps.
     
    #3 King_V, Apr 17, 2026 at 5:42 PM
  4. Mendel Leisk

    Mendel Leisk MMX GEN III

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    Have a look at the rear brake drag link in my signature, might be related.

    (on a phone turn it landscape to see signatures)
     
    #4 Mendel Leisk, Apr 17, 2026 at 8:28 PM
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  5. BiomedO1

    BiomedO1 Senior Member

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    You need to remove both caliper bolts. Some pads has an indexing nipple that slots into the piston. Don't know if yours operates like that. I'm pretty sure that's why you couldn't just rotate the caliber out of the way - like you would do with a front caliber. If it has that indexing nipple - it must be aligned when you put it back together, otherwise you'll be dragging a pad; once the piston pushes back out.

    Hope this helps...

    Yes; don't forget to disconnect the battery - you don't want the piston pushing themselves out.
     
    #5 BiomedO1, Apr 17, 2026 at 10:03 PM
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  6. Fubar XIII

    Fubar XIII Member

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    Vehicle:
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    Model:
    Two

    Been there, done that. Twice now.
    My first set lasted 230,000 miles, though they were THIN. Should've done at 200k. Ok, maybe 175k. Live & learn.
    Second set only went about 105k. Those were semi-metallics. Turns out we're supposed to use ceramics. And I thought those were just for high-performance sports cars, et cetera. Put a new set of ceramics on last summer.

    As for the plus sign in the rears, that messed me up, too. I'd never had to do anything like that before. First time I actually cranked it so far the screw came out of the nut. Yup, you can do that! If you go the wrong way. After a few minutes of fumbling around I got it re-threaded and then knew which direction I was supposed to go. Trial & error. You learn more from your mistakes.....
    As for how to twist said part, I went with a pair of medium-sized channel locks. The jaws are solid & won't pop off easily, you can, of course, adjust them, and they put pressure on both sides at the same time which really seemed to make things move a bit quicker though nowhere near fast. Be patient. I held the jaw end of the pliers in my hand and left the handles sticking out the side so I could apply pressure straight down on the part. It doesn't take much force to move it but there is a steady resistance to it, as if you are turning something through thick grease. Steady pressure worked great.

    After you get the screw in far enough to put the caliper back on, you're good.
     
    #6 Fubar XIII, Apr 19, 2026 at 2:14 PM
  7. Mendel Leisk

    Mendel Leisk MMX GEN III

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    These gizmos work good:

    upload_2026-4-19_12-17-12.png

    Lots of brands available.
     
    #7 Mendel Leisk, Apr 19, 2026 at 3:17 PM
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