Rattle underneath 2010 Prius at 25 - 30 mph

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Ross Edwards, Mar 13, 2018.

  1. Ross Edwards

    Ross Edwards Junior Member

    Joined:
    Jul 5, 2013
    5
    0
    0
    Vehicle:
    2007 Prius
    Model:
    II
    Just purchased 2010 Prius yesterday, and I can hear a slight rattling possibly coming from left side of car - seems to be underneath. I don't think it's engine.
    Comes on at around 25 - 30mph without fail, but also at slower speeds,& more so under medium acceleration. I can hear it more when passing close to a hedge or walls on the left. and very clear when I open the windows on the left side. I don't know if it continues after 35mph as road noise seems to take over.
    It's done 60k with last service at 54k
    I did 200 mile journey and got 60mpg on the computer. checked oil and it looks clear and at full mark.
    Could this be something as simple as exhaust shielding? or should I focus on brakes
     
    #1 Ross Edwards, Mar 13, 2018
  2. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    112,660
    51,280
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    yes, and there is more than exhaust shielding under there. there is a whole aero platform with poor design oil flap door. climb under, or put her on a lift.
     
    #2 bisco, Mar 13, 2018
    Grit and Mendel Leisk like this.
  3. Grit

    Grit Senior Member

    Joined:
    Aug 22, 2017
    6,486
    4,204
    1
    Location:
    Wilkes Land
    Vehicle:
    2012 Prius
    Model:
    Four
    Could be a rock trapped in between the plastic under carriage and vehicle chassis, rattling around. I test drove a Prius 2011 trim 4 w/o HUD package and same thing happens but at 40-45 mph.
     
    #3 Grit, Mar 13, 2018
    Mendel Leisk and Raytheeagle like this.
  4. Ross Edwards

    Ross Edwards Junior Member

    Joined:
    Jul 5, 2013
    5
    0
    0
    Vehicle:
    2007 Prius
    Model:
    II
    I've got it going to my mechanic to check a steering knock issue on Fri, so I'll get him to look at it on the ramp. More than anything I just want to rule out engine, otherwise I'd need to look at getting it back to dealer for refund. I can certainly deal with anything fairing related.

    It's not particularly easy to identify rattles whilst stationary that only appear at certain rpm's as you can't rev these cars!
     
    #4 Ross Edwards, Mar 13, 2018
  5. Raytheeagle

    Raytheeagle Senior Member

    Joined:
    Jul 1, 2016
    11,263
    15,512
    0
    Location:
    Bay Area, California
    Vehicle:
    2019 Prius Prime
    Model:
    Prime Plus
    If taking it to the mechanic, some other things for him to check:
    • Wheel bearing hub failing
    • Brake pad thickness
    • Failed boot on the strut tower
    • Wheel cover not fitting correctly
    Hope that helps(y).
     
    #5 Raytheeagle, Mar 13, 2018
    Bay Stater and Grit like this.
  6. Grit

    Grit Senior Member

    Joined:
    Aug 22, 2017
    6,486
    4,204
    1
    Location:
    Wilkes Land
    Vehicle:
    2012 Prius
    Model:
    Four
    Just realized it could be a fasten secure missing from one of the under carriage, at a specific r/ange of speed, part of the loose under carriage flaps as air passes through. Lift the ca/r and check for any missing fasteners.

    If not that, pound the carriage upwa/rds nea/r the vicinity where rattling is coming from, you might hea/r a rock/gravel moving a/round, or see a broken/loose flap pa/rt of the under ca/rriage.
     
    #6 Grit, Mar 13, 2018
    Bay Stater and Raytheeagle like this.
  7. Ross Edwards

    Ross Edwards Junior Member

    Joined:
    Jul 5, 2013
    5
    0
    0
    Vehicle:
    2007 Prius
    Model:
    II
    Thanks for tips
    That is not a missing bit in pic below I assume?
     
    #7 Ross Edwards, Mar 14, 2018
  8. Ross Edwards

    Ross Edwards Junior Member

    Joined:
    Jul 5, 2013
    5
    0
    0
    Vehicle:
    2007 Prius
    Model:
    II


    not sure why imgur links are now working?
     
    #8 Ross Edwards, Mar 14, 2018
  9. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    112,660
    51,280
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    can't see anything.
     
    #9 bisco, Mar 14, 2018
(You must log in or sign up to post here.)