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8mm at 32K, is that normal?

Discussion in 'Gen 4 Prius Care, Maintenance and Troubleshooting' started by ykbj, Jul 29, 2019.

  1. ykbj

    ykbj Junior Member

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    Recently came back from the dealer, brake pads for all four corners measured 8mm at 32k km, 20k miles. Is that normal wear?

    I live in the great North and I have only been thru 1 winter. I do, however, do a lot of town driving, stop and go in downtown.
     
  2. 2k1Toaster

    2k1Toaster Brand New Prius Batteries

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    If you drive like most people on the 401, that would be normal.

    It all has to do with how often you use the friction brakes. Brake slowly and you use regen down to 7mph so your brakes last forever. Panic stop, or do lots of coasting at less than 7mph and you have no advantage. My guess is lots of stop and go, mostly creep, and then fast accelerations to fast stops are what is eating your brakes. And in that area, totally normal.
     
  3. alanclarkeau

    alanclarkeau Senior Member

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    I posted recently "They said there's over 10mm left - and considering that there was only 12-13mm originally, at this rate they said I should be right for 200,000+ km. It's driven 45,342 kms - which GOOGLE tells me is 28,174 miles."

    Someone posted later that NEW, there is only 10mm Fr, 9.5mm Rr. Which - GOOGLE search confirms. So - there's got to be less than 10mm!!!

    My suspicion is that they didn't measure it, but eye-balled it.

    I'll ask again at the next service. Or climb underneath and have a close look.

    UNLESS - They're measuring it to include the backing plate like BENDIX mention:

    upload_2019-7-30_9-56-41.png
     
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  4. Vman455

    Vman455 Senior Member

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    ^^^Yeah, I think Toyota's spec is without backing plate, but the easiest way to measure pad thickness is with a set of calipers.

    OP, that wear is totally normal--at the rate you're going, those pads should last you upwards of 100,000 miles. As 2k1toaster said, some changes to your driving style and you could go much further on the originals (I almost never use friction brakes above 7 mph, and my pads at 80,000 miles look almost new). Every few years, grease the slide pins, especially the rears, or they may start to eat the pads.
     
  5. ykbj

    ykbj Junior Member

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    First of all, thx for the reply everyone^^ Definitely appreciate it!

    I do travel a lot on 401 and the core GTA area. The problem on 401 or any major highway in the city is you have so many entrances and exits with people getting on and off. So you would be picking up speed right up to 120km/h and then drop to dead zero in just a matter of minutes.

    I will definitely be keeping a close eyes on the slide pins and make sure it's properly lubricated. Although at this rate the pads should only last me 130000 km. Hopefully they are not expensive to replace at the dealership. Trying to save every pennies!
     
  6. kithmo

    kithmo Couch Potato

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    Toyota spec has got to be without backing plate as the minimum (thinnest) thickness is less than the thickness of the backing plate.
     
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  7. Mendel Leisk

    Mendel Leisk Senior Member

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    We're at around 83K kms (a bit over 50K miles) and last time I had the wheels off the fronts looked to be about 6 mm remaining (new thickness is 10). Just eyeballing it; it's another year till I do my next full inspection.

    It's a third gen, but the new thickness are the same.

    Here's my log notes, from my last check:

    ====
    Thursday, March 23, 2017
    km: 66402
    * inspected front brakes, pads disassembled and lubed, calipers pins relubed
    remaining thickness (all): 7 mm (roughly)
    ====

    (Rears have even more, maybe 8mm now. I messed up on my first inspection of the rears, resulted in bevelled wear, and I replaced rear pads preemptively.)
     
    #7 Mendel Leisk, Jul 31, 2019
    Last edited: Jul 31, 2019
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  8. Vman455

    Vman455 Senior Member

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    If you're at all handy, they're pretty easy to replace yourself. Disconnect the 12v battery, let the car sit for several hours to depressurize the brake system, pop the brake fluid reservoir cap. Fronts are a sliding piston design so they get pushed straight in, while the rears with integrated e-brake are a typical rotating design, so you need a pair of needle nose pliers or a disc brake tool (plate with two nubs on it) to rotate them into the caliper. Other than that, it's pull out the old pads and put the new ones in, aligning the nubs on the rear pads with the concavities in the pistons, easy-peasy. If you can grease the sliding pins yourself, you can replace the pads, so I would say when the time comes, go for it!
     
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  9. liquidtenmillion

    liquidtenmillion Active Member

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    I know dealers frequently eyeball it, maybe every single time because when I was in my free service period I had 2 extra MM more then I had on the previous "inspection". The brakes certainly didn't grow in that time period.
     
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  10. Mendel Leisk

    Mendel Leisk Senior Member

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    I did my first brake inspection at 43K kms, and the fronts were around 7.5~8.0 mm, the rears around 7.5~7.0. So yeah, in the ball park. This is 3rd gen, but similar I think.

    I find a tire tread depth gauge more convenient, accurate enough. Most calipers do have a similar depth gauge, and that's what you need to use, since the backing plate gets in the way if you attempt to use the regular jaws.
     

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  11. ykbj

    ykbj Junior Member

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    I was in dealership for 48k km service and the brake pads on front and rear grew back to 9mm and 8.5mm respectively.
     
  12. bisco

    bisco cookie crumbler

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    magic toyota pads
     
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  13. kithmo

    kithmo Couch Potato

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    Regeneration of the pad material ?
    You better get them changed before they get too big. :LOL: