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New 12 volt battery improved MPG

Discussion in 'Gen 2 Prius Fuel Economy' started by aolm, Apr 15, 2011.

  1. aolm

    aolm Junior Member

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    My 05 battery was showing 9 volts on the MFD... and we got the red triangle a couple of times on start up. I have read on the site that my MPG might go up with a new battery and I have picked up 4-5 MPG's. I thought my low MPG"S were due to aftermarket tires. The battery was $250 (you have to use the dealer)... a lot for a car battery but it will pay back a little every fill up. I'm gently driving to about 51mpg.
     
  2. F8L

    F8L Protecting Habitat & AG Lands

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    That is great news. :)

    YouCan also purchase and install an Optima D51 yellow top battery. They are cheaper, higher cranking amps and a deep cycle battery. Installation is a little more complex than the stock battery but instructions included with the purchase make it simple.

    Elearnaid.com sells the optima kit for $180.
     
  3. aolm

    aolm Junior Member

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    Can you post the instructions?
    Tks
     
  4. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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  5. F8L

    F8L Protecting Habitat & AG Lands

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  6. richard schumacher

    richard schumacher shortbus driver

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    $250 is a bit steep for an OEM battery with dealer installation. MSRP is about $140. Five years from now when it needs replacing again look for a dealer who will do the job for $200 or so.
     
  7. mlbumiller

    mlbumiller Junior Member

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    I was just quoted $367 for the aux 12v battery plus $99 install @ Temecula Toyota CA

    Told the high price is due Prius is only vehicle to use that size battery.
     
  8. MJFrog

    MJFrog Active Member

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    Find a more reputable stealership if they're going to charge that much.
     
  9. ystasino

    ystasino Active Member

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    First, 9V is so low, I am wondering whether it is an erroneous reading. Is 9V sufficient to power up the car?

    I got mine for ~ $178.37, changed at 11.9V w/o charge and got quoted as high as $320 and $240. Shop around.
     
  10. cwerdna

    cwerdna Senior Member

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    As I answered in another thread. Run away! That's a TOTAL ripoff.

    I changed it myself to Toyota Prius 12 Volt Auxiliary Battery with install kit for 2004 - 10. There is no cost savings going w/the Optima battery but there are claims that it's superior to the OEM one.
     
    1 person likes this.
  11. Oldwolf

    Oldwolf Prius Enthusiast

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  12. mlbumiller

    mlbumiller Junior Member

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    thanks !! i am taking this quote to my dealer ship and getting the parts manager and general manager to explain the dealerships rip off price
     
  13. striker308

    striker308 Three time Prius owner

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    i just had to get one last night. North town Toyota in williamsville NY had the Blck one(the one used in the pri w/nav and smart start) for $138.97 after NYS got the taxes it cost me $157.62 there was no core charge and that confused me as EVERY other battery I have ever gotten for one of my cars had a core charge. The guys there also told me to swing by Sears hardware and pick up a 12V lawnmower starter battery ($12.93 w/tax) and hook it to the Jump start connection and ground under the hood so I could keep all the memory and settings when changing the Aux Battery. They even asked me if I had brought the car in for the inverter coolant pump swap yet. Good crew over there...... Much better than at Fuccillo Toyota where I bought the car.
     
    Max Finch and garglo like this.
  14. 05azprius

    05azprius New Member

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    out of curiosity, why would anyone pay to replace a battery???

    oh and my MPG has sucked...i've had the car for a month, the 12v was dead from sitting after the accident (unknown timeframe sitting), i ran my "special" battery charger on it (brings them back to life by desulfating) and it has been holding charge ever since, however i started with around...42-45mpg, and it has been slowly decreasing, down to 36mpg average. also there are no other signs of issue except i noticed my mpg screen keeps resetting.

    i went in to the battery voltage display and it says 9.8V. going to go grab my battery tester and load it down, and see what happens (if it kills it...it kills it, autozone says they have the optima d51 in stock for $166 here, toyota dealer quoted me $99 for oem, i claimed i was a shop and they told me $72)
     
  15. 05azprius

    05azprius New Member

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    battery failed the load test...
     
  16. richard schumacher

    richard schumacher shortbus driver

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    And that's why people pay to replace them.
     
  17. 05azprius

    05azprius New Member

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    i understand why you PURCHASE a new battery, i don't understand why you would pay someone $50-100 to INSTALL something that takes 10 minutes and a pair of pliers.
     
  18. richard schumacher

    richard schumacher shortbus driver

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    Ah! Thanks for the clarification.
     
  19. Solar1953

    Solar1953 Junior Member

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    After reading all this, and the fact that my 07' mileage is down from the usual 42 MPG or so that I usually get to around 40 or even less, I am looking into replacing teh 12V battery; My question is: are there any tricks to replacing it, or any step-by-step procedures that must be followed? Or is it as simple as, was stated above, using a pair of pliers (actually wrench) and about 15 minutes work?
     
  20. richard schumacher

    richard schumacher shortbus driver

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    I lean pretty hard to the follow-the-steps side. How to remove the ventilation covers and the multiple attached cables safely may not be obvious, and it is annoyingly easy to lose a particular bolt and screw into certain dark deep body spaces. Maybe I'm slow, but it took me a good hour to install an Optima using eLearnaid's very good kit, their instructions and every one of the tools they call out (and I wish I'd had a bench vise also, to help get that dang positive clamp loose). Swapping in an identical Toyota battery should be a bit easier but if you've never swapped a battery before think carefully about making this your first.