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

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    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

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    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
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  3. Grit

    Grit Senior Member

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    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
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  4. Ross Edwards

    Ross Edwards Junior Member

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    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

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    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
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  6. Grit

    Grit Senior Member

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    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
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  7. Ross Edwards

    Ross Edwards Junior Member

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    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

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

    bisco cookie crumbler

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    can't see anything.
     
    #9 bisco, Mar 14, 2018
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