1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Transmission fluid replacement?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Gando, May 30, 2021.

  1. Gando

    Gando New Member

    Joined:
    May 29, 2021
    1
    0
    0
    Location:
    Nashville
    Vehicle:
    2015 Prius
    Model:
    IV
    Do I need to drain & replace transmission fluid on my 2015 at 164K?
     
  2. xliderider

    xliderider Senior Member

    Joined:
    Apr 19, 2012
    7,869
    3,116
    0
    Location:
    Honolulu, HI
    Vehicle:
    2011 Prius
    Model:
    Three
    Are you the original owner? Has the transaxle fluid ever been drained and replaced?

    How long are you planning on keeping this car?

    Posted via the PriusChat mobile app.
     
    Valiant V likes this.
  3. jerrymildred

    jerrymildred Senior Member

    Joined:
    Oct 28, 2016
    11,508
    14,110
    0
    Location:
    Tampa, FL
    Vehicle:
    2017 Prius
    Model:
    Two
    No, but you probably should. Most owners, I imagine, never change it and don't have a problem. But it's cheap and easy, and it might prevent a problem. When you drain it, you might be surprised at how dark it is compared to new stuff. Just make sure it's the Toyota ATF-WS.
     
  4. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    55,539
    38,709
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    My opinion, the optimum time for transaxle fluid change is after the cars been on the road about 10k miles. So yeah, time for a change.
     
    Grit and jerrymildred like this.
  5. Too Old to Clean EGR

    Too Old to Clean EGR Junior Member

    Joined:
    Jan 21, 2020
    15
    11
    0
    Location:
    Los Angeles, CA
    Vehicle:
    2010 Prius
    Model:
    II
    I have not seen an official transmission fluid replacement schedule, although I have seen on this forum that Toyota has mentioned 130,000 miles, in some context, so I changed mine at 120,000 miles and plan on changing it in 60,000 mile increments going forward. My old fluid looked fine. It was just a little darker than fresh fluid. I would go ahead and change the fluid at any mileage if you think it has not been changed. Unlike a traditional transmission, you do not have to worry about the transmission slipping after replacing worn fluid, you just want to keep the planetary gear lubricated. Actual failure of the gears seems to be rare but presumably the electric motors are at least partially lubricated by the fluid.

    Changing the transmission fluid is not much different than changing the oil. It does not have a torque converter, so most of the fluid drains right out. There are plenty of threads on replacing the fluid and there is a NutzAboutBoltz video. Just have a 10mm hex socket, two crush washers (Toyota calls them gaskets), 4 quarts of Toyota WS fluid, and a pump or a few feet of hose and funnel to refill the transmission. Also, make sure you can get the upper fill plug open before you open the bottom drain plug.
     
    Mendel Leisk likes this.
  6. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    55,539
    38,709
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    29 ft/lbs is the spec for fill and drain bolts. Level is correct, if you fill with the car level, till it starts coming back out. FWIW Toyota cautions to only use freshly opened bottles (of Toyota ATF WS).
     
    Valiant V and Grit like this.
  7. Grit

    Grit Senior Member

    Joined:
    Aug 22, 2017
    6,147
    4,057
    1
    Location:
    Wilkes Land
    Vehicle:
    2012 Prius
    Model:
    Four
    so you can just raise the front up?
     
  8. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    55,539
    38,709
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    cmon, just cus he said it’s like an oil change you start baiting him??
     
    Grit likes this.
  9. Grit

    Grit Senior Member

    Joined:
    Aug 22, 2017
    6,147
    4,057
    1
    Location:
    Wilkes Land
    Vehicle:
    2012 Prius
    Model:
    Four
    but Toyota says lifetime fluid also? So no need to worry about fresh open bottles because no need to change :LOL:
     
  10. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    55,539
    38,709
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Cmon…
     
    Grit likes this.
  11. Grit

    Grit Senior Member

    Joined:
    Aug 22, 2017
    6,147
    4,057
    1
    Location:
    Wilkes Land
    Vehicle:
    2012 Prius
    Model:
    Four
    just looking out for the people who follows instructions carefully. There’s been 3 people who bought a charger because they were told on here to do so and there were no 120 outlets near their car to plug in the charger. Happened one feller yesterday :ROFLMAO:
     
    #11 Grit, Jun 4, 2021
    Last edited: Jun 4, 2021
  12. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    55,539
    38,709
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Hey, people without computers bought boxed Windows95 when it first came out.
     
  13. Ed Beaty

    Ed Beaty Active Member

    Joined:
    Jul 13, 2018
    334
    309
    0
    Location:
    Salt Lake City
    Vehicle:
    2010 Prius
    Model:
    IV
    "cmon, just cus he said it’s like an oil change you start baiting him??"

    This is his essential (to him) task on PriusChat...