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Wheel bearing cost me 7-8mpg?

Discussion in 'Gen 2 Prius Fuel Economy' started by 80sguy, Jan 23, 2023.

  1. 80sguy

    80sguy Junior Member

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    *** I tried posting this before but I don't think I did it right so if it is on here twice, sorry***
    Hi folks, thanks for all the helpful information. Newer member but I learned a lot. I just replaced my '08 Prius with a second OE Prius, first one dueled with a deer and lost.
    We actually have three Priuses in the family and most get very similar gas mileage depending on who's driving and conditions, 43 to 49. The new one I just got is going to need a wheelbearing in the not too distant to near future. Could this have a significant effect on gas mileage? This gets 36 or 37 miles per gallon. It has 225 k on the odometer which is 35,000 less thin my previous '08. Put in a new 12 volt battery because it seemed like the ICE ran more then it should compare to my other ones. Plus I think that battery might have had a bad cell according to my charger. Like I said, the wheel bearing is not terrible at this point and while it's on my radar, I'm wondering whether I should keep this Prius and move on to something else. Since I live in deer country and my kids drive these cars a lot, As long as I'm only going to get mid to high 30s, there are other options that are bigger and safer. Please let me know what you think. By the way, recent oil change of 5W30 synthetic.
     
  2. alftoy

    alftoy Senior Member

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    Have you used a grid charger on any of your current Pri?

    The condition of the hybrid battery in the new to you Pri probably has much to do with lower mpg.
     
    #2 alftoy, Jan 23, 2023
    Last edited: Jan 23, 2023
  3. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    Wheel bearing isn't costing you that much. They can make a very loud racket with not much energy cost to the car.

    Something else is wrong.
     
  4. Kenny94945

    Kenny94945 Active Member

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    I doubt a working but worn, wheel bearing would "cost" 7-8 MPG.
    One quick test could be to drive and see if the hub/ rim is hot....eg bearing drag.

    It could also be possible the bearing has failed so much that wheel alignment is affected.
    But affected to 7-8 mpg...I vote no.
    But tire brand or wear might be the that 7-8 cost.

    I also agree with Leadfoot, there could be a noise, in my experience when a bearing fails, you know it.
    I also tend to think with such high mileage, you have a "worn" hybrid battery.

    Can't comment on whether you should stay with a Prius, yet this is a Prius forum :)
    Good luck.
     
  5. 80sguy

    80sguy Junior Member

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    That's what I was afraid of
    Grid charger? I assume that's for the hybrid batt...
     
  6. 80sguy

    80sguy Junior Member

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    Ty
    I think it's pretty slight wear...barely hear it, only when turning hard
     
  7. ColoradoCrow

    ColoradoCrow Active Member

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    Noise while turning? Did you check your CV Axles? Check the boots for rips and or tears? with 3 Prii in your family.Do you have the paid version of Dr. Prius. I think that software allows 3 cars. They you can run the battery tests in it. Sounds like the life of that battery is in question.
     
  8. 80sguy

    80sguy Junior Member

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    So I got the doctor Prius app and I got one of the OBD plugins that was recommended on the site. Stupid question but I cannot find where you buy the paid Dr. Prius. I just have the free one
     
  9. 80sguy

    80sguy Junior Member

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    What do you mean by grid charger?
     
  10. alftoy

    alftoy Senior Member

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  11. 80sguy

    80sguy Junior Member

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  12. JoeB

    JoeB Junior Member

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    I would start by cleaning the intake, putting a fresh air filter in, changing the PCV valve, installing new plugs, running a good fuel system cleaner through two tanks of gas, and driving the crap out of the engine for an hour before before assuming the bearing is at fault. It is just there are so many places that fuel inefficiency can happen that presuming it is due to a known problem is often wishful thinking.