1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Possible bearing noise? 2018 C

Discussion in 'Prius c Care, Maintenance and Troubleshooting' started by Chetallica, Jun 5, 2024.

  1. Chetallica

    Chetallica Junior Member

    Joined:
    Jul 11, 2019
    15
    4
    0
    Location:
    Mid-Atlantic area
    Vehicle:
    2018 Prius c
    Model:
    One
    Hi Everyone,
    Getting a slight "howl" between 35 and 50 mph. When windows up, seems to be coming from the rear, and is louder than windows down. It's odd that it is only between these speeds though. No noticeable vibration, or pulling and zero dash light warnings. Also does it on straightaways and cornering.
    I am thinking it may be a bearing. Only have 80,000 but car does get driven pretty hard at times on less than desirable streets to and from work.
    Plan to run it in circles on a lot and then jack it up and do the "pull on wheel" test to see if I feel and looseness. Have a full brake replace coming up (drums, discs, etc) so may be a good time change the bearings (rear looks like no fun...) but also hoping maybe I'll find something when tearing down the brakes, although I would think something lodged in the disc or drum would cause noise all the time and not at certain speeds.

    Just throwing this out here to see if anyone has had the same issue with the speed and so on.

    Appreciate an input!
     
  2. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

    Joined:
    May 12, 2018
    7,427
    6,912
    1
    Location:
    Pennsylvania
    Vehicle:
    2018 Prius c
    Model:
    Two
    You ride the lightning but don't care to hear the thunder eh? :ROFLMAO:

    Our car had a bad rear wheel bearing around 71k miles.

    I paid a local mechanic $500 to replace the bearing. He did the job fast and we rolled out. The replacement bearing did not last.

    summary of linked thread: the new bearing had burst a grease seal and was oozing grease everywhere, including in the wheel speed sensor.

    I bought a $70 tool and I took the time to fix it myself with a $340 part from Toyota. Learned my lesson on that one.

    Good luck!
     
    Danno5060 likes this.
  3. Chetallica

    Chetallica Junior Member

    Joined:
    Jul 11, 2019
    15
    4
    0
    Location:
    Mid-Atlantic area
    Vehicle:
    2018 Prius c
    Model:
    One
    Nice user name to song correlation, well done! :)

    Thanks for the info and link. I revisited and tried to evaluate the actual sound after seeing some vids about Prius bearing noise (more like vibration and grinding). I have had bearing issues in the past, but talking older cars, like 70's and 80's and they did not sound like this. But this being my first hybrid, trying to be sure.
    Not sure howl was the best descriptor. Whirl maybe? Think I may try and throw the phone in the back when I get up to 35-50 and see if I can record the sound.
     
  4. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

    Joined:
    May 12, 2018
    7,427
    6,912
    1
    Location:
    Pennsylvania
    Vehicle:
    2018 Prius c
    Model:
    Two
    The sounds get described a lot of different ways, which is probably accurate because most of these cartridge bearings change sound over time.

    They start silent, then you get a whir, then a bit more of a howl, and when they're in really bad shape it's a drone worthy of a WWII bomber.

    They are insanely good at ventriloquism. You can be ready to bet everything it's THAT one, and... it isn't. Best diagnosis I know of is through a tool called Chassis Ears, but not every shop has one.

    Sometimes you can just lift each wheel and spin them by hand. They should be dead silent, a bad one will usually give a tick-tick-tick like a card in the bike wheel spokes when you were 10.
     
  5. Chetallica

    Chetallica Junior Member

    Joined:
    Jul 11, 2019
    15
    4
    0
    Location:
    Mid-Atlantic area
    Vehicle:
    2018 Prius c
    Model:
    One
    Got the car up in the air on both sides today and gave each wheel a good spin. Both fronts had typical, very light axle sounds as they rotate in N. Left rear, silent. Right rear, diff story: not super loud, but a definitive low "thumping" sound.
    I tried to capture the sound on the vid, you can hear it for sure. Sorry for bumping and phone sounds, I was trying to get as close as I could to the rear axle.



    So next issue, there are only two bolts visible from the backing plate and both are impossible to get a socket on. I am thinking the bolts will be accessible once the brake drum is removed. I am going to check the link above, but am in search of a removal and install procedure for 2018 C hatchback drum brakes. Also, wonder if I will need a code rest after unbonneting the speed and regenerative connector.
    If anyone has a direct link that would be awesome! I want to be prepared before I tear it down next week for the full brake overhaul and hopefully the bearing replacement.

    Always appreciate and input :)
     
  6. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

    Joined:
    May 12, 2018
    7,427
    6,912
    1
    Location:
    Pennsylvania
    Vehicle:
    2018 Prius c
    Model:
    Two
    Rear bearing replacement is super easy.

    Use your safest implement to lift the wheel in question, secure the car on stands.

    Remove the wheel. (4 lug nuts)

    Remove the drum (it slides off, unless you set the parking brake)

    Remove the wheel speed sensor connector from the backside. Mind the plastic strain relief clip.

    Remove the wheel bearing (four bolts, easily accessible with a socket wrench. Just spin the hub flange until one of its holes lines up with the bolt head, and you can get right in there.)

    Reassembly is the reverse. Took me all of 25 minutes. You can see a picture of my right rear wheel opened up on that link I posted earlier.

    The official instructions are in the repair manual, accessible from this link. I doubt it's worth a 2-day subscription just for a rear wheel bearing, but it's there if you need it.

    You'll need a Prius-savvy scan tool to reset the codes. I used an Autel AP2500E, and I like it. The AP200 is another good choice.

    Good luck!

    (Edited to add sensor wire step for future readers)
     
    #6 Leadfoot J. McCoalroller, Jun 10, 2024
    Last edited: Jun 10, 2024
  7. Chetallica

    Chetallica Junior Member

    Joined:
    Jul 11, 2019
    15
    4
    0
    Location:
    Mid-Atlantic area
    Vehicle:
    2018 Prius c
    Model:
    One
    Thanks again for all the info, you have been a huge help! I imagine my vid with the sound was the toggle, that yea, I have a bearing issue :(

    I saw some vids where the bearing bolts were accessed from the back by the axle (prob and older model) and when I was under there I saw no access at all. So on this year, they are accessed through the hub holes. Nice!
    I am replacing brake shoes and drums so since I will be that deep, this should be easy to get to.
    Thanks for the code tool tip too!
     
  8. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

    Joined:
    May 12, 2018
    7,427
    6,912
    1
    Location:
    Pennsylvania
    Vehicle:
    2018 Prius c
    Model:
    Two
    Sure you want to? It's pretty normal for Prius brake hardware to go well over 100k without needing replacement. The picture of my wheel opened up at 76k miles shows almost full depth remaining on those shoes, and that's fairly typical for a Prius.

    One step I forgot to mention in above: the wheel speed sensor connector. It'll be quite obvious, and it only adds a couple of minutes. The wire goes in through the backing plate, so remove that before unbolting the bearing, and do the reconnection last after the new one is in.

    There is a weird plastic coupler involved- not much to it but it took me two tries to work out how it went together.
     
  9. Chetallica

    Chetallica Junior Member

    Joined:
    Jul 11, 2019
    15
    4
    0
    Location:
    Mid-Atlantic area
    Vehicle:
    2018 Prius c
    Model:
    One
    I drive some pretty intense roads back and forth to work, and started to get some decent front disc wear. Checked the pads 2 weeks ago and they looked pretty good but have not pulled the drums yet.
    I was kind of prepping for an overhaul so got the complete DetroitAxle kit (discs, drums, springs, pads, etc) so I had everything if I needed it soon. Have used their brake products for years (I also have a Sienna) and quality and wear has been really, really good, so happy with their stuff.
    Am thinking if I pull the drums and everything looks good there, I might just hold off on the overhaul if I can get another 10 or 15 out of the original brakes. Keeping this car for the long haul, so if I wait, I at least have everything I need when I am ready to do everything.
    I did see the info about the coupler, noted and do not want to break the plastic clips, that's for sure!
    Thanks again for all the info! (y)