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My recent Prius C transmission experience

Discussion in 'Prius c Care, Maintenance and Troubleshooting' started by eyecue, Dec 1, 2020.

  1. eyecue

    eyecue New Member

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    After reading about the Prius C air-cooled P510 transaxle, and some of the owner's experiences with it
    I decided to have my PC's transaxle fluid changed at 39,000 miles. The service manager at Toyota refused my request saying it would be a waste of money because this was a lifetime fluid. I then took the car to an independent mechanic who showed me that the drained factory fluid was very black and had a burning smell compared with the replacement Toyota ATF WS. The mechanic who has 20 years experience in transmission service suggested to change the fluid again after a couple of months to finish cleaning out the residues of the old fluid from the transaxle, and then every 30k/40k miles. For a combined cost of $240 for the two fluid changes, I personally consider this a good investment, given that this fluid not only lubricates the CVT gears but also helps cool the rotors and stators of the 2 electric motors within the Prius C transaxle.
     
  2. Max Taiwan

    Max Taiwan Active Member

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    I recently did a fluid change by myself. It was a little tricky pumping the fluid in but at the end it was very rewarding.
    My change was at around 60k km. Fluid was dark Red.
    If i were to DIY again I will use a electric pump, I did a manual crank pump.... took 15min to fill up.
     
  3. PriusII&C

    PriusII&C Active Member

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    I have two Prius: Gen3 Prius and Prius C. Both are year 2012 models. After reading many recommendations on Priuschat forum, I changed my 2012 Prius ATF by myself at 60,000 miles. The ATF looked fresh red, plug was clean too. So I postponed my 2012 Prius C ATF change until 100,000 miles. Again the fluid still looked quite clean, and no much deposits/dirt on the plug. This experience makes me to doubt the necessity of early ATF change. FWIW, I live in the Bay Area. Not sure if it has anything to do with it.

    Some people have done extension fluid analysis, and found out that there are metallic materials even at much early ATF change. So it becomes a personal opinion on when one should change their ATF. Of course, it doesn't hurt to change it early as a preventative measure.
     
    #3 PriusII&C, Jan 28, 2021
    Last edited: Jan 28, 2021
    michael.sfo likes this.
  4. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    That's in fact a Toyota dealership. Maybe post the name of the place, for local Toyota owners who don't like dealing with an adversarial service manager.

    Hopefully they used Toyota ATF WS? If you can DIY, four quarts of this at dealership part counter is around $40, and the drain and fill is on par with an oil change, maybe even simpler. I wouldn't bother with a second change; the drain-and-fill removed roughly 90% of the original fluid.

    Using a funnel and hose from above is very easy.
     
    #4 Mendel Leisk, Jan 28, 2021
    Last edited: Jan 28, 2021
  5. dubit

    dubit Senior Member

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    I passed on trying from above. Feeding that down, and then getting it to stay in the hole. So I used an outboard motor fuel hose & bulb like the one found here: GZYF 3/8" Marine Outboard Boat Motor Fuel Gas Hose Line Assembly W/ Primer Bulb - Walmart.com - Walmart.com

    I found the fluid in my transmission to be very dark however. Unlike the individual above. Have any of you also noticed that vibration we all seem to get right around the sweet spot when your car could either switch to full electric or stay running gas was reduced after the transmission fluid change? While it's still there, it's very much reduced.

    Oh, I did utilize Toyota fluid.
     
  6. fermuscolo

    fermuscolo Member

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    My Prius C 2012 has just reach 100.000 miles, never changed ATF, Its ok to change it now? Also Do I have to change Inverter coolant? Thanks
     
  7. topshot

    topshot Member

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    I would change ATF at least with Toyota WS. Inverter coolant is supposedly 150K (on my 2015 at least), but no harm in changing it now if you want. You should do the radiator coolant now though.
     
  8. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    I plan to do ours around 50k miles, which will likely be late spring. And then I'm maybe going to check up on this thread in 7 years to see if a second change is worth it.

    The point is I think one change is worthwhile; not sold on the value of a second or beyond when considered with our expected usage.
     
  9. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Have done 3 changes (on a 3rd gen), first around 15k kms, 2nd and 3rd progressively spread out: first was by far the darkest, second so-so and third pure overkill. In hindsight: that first one only, at those kms (aka 10k miles), seems prudent. If you do a second, maybe around 50k miles, or more. This all hinges on fluid “appearance”.