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Should I change the transmission fluid at 25K/3 years of ownership, or not?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by LulzChicken, Jul 15, 2012.

?
  1. Yes

    31 vote(s)
    59.6%
  2. No

    21 vote(s)
    40.4%
  1. adamace1

    adamace1 Senior Member

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    Wanted to update. I drained and filled the transaxel today. No matter how i leveled the car it was still 1/2 inch below the fill plug before the drail/fill. Took about 3.1 quarts old fluid out, and 3.7 quarts in. The old fluid was nasty, when i got some on my finger when i was checking it it was blacker than most used oil i have seen. When i drianed it and used a white cloth to clean the spills up the rag turned pitch black. There was no signs that the fluid had any red tent in it.

    What you guys think.
    1. I used toyota ws atf
    2. After filling it till it ran out i drove a few miles then leveled the car again. When i pulled the plug none came out but it was 1-3 mm from the threads on the fill plug.
    3. I'm confused on the whole level your car thing, i tried raising and lowering the back with jacks but it made no difference in fluid level. I used ramps under the front tires.
    4. I have not seen atf this dirty before.
     
  2. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Sounds like your existing fluid level was at the low end of acceptable (maybe somehow some was consumed??), and you've got it right now. Interesting to hear about the fluid quality: how many miles on it?
     
  3. edthefox5

    edthefox5 Senior Member

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    Yes this gearbox is very hard on the fluid. The only other manual transmission I have ever owned that required
    D4 auto fluid was in a Ford Ranger 5 speed. That trans was not half as hard on fluid as the Prius. I used to change that fluid every 30,000 using Redline D4 as that fluid if somewhat fresh fixed the 2 gear snick on that truck and the fluid still looked pretty good at that interval.
    The Prius trans turns the fluid pretty dark even after after 5K miles. Which is when I did my first change to Redline D6. Lot of run in wear. I expect it to get better as time goes on.

    And as far as the level thing don't worry its hard to level it front back enough to make a difference because your changing the length of the car not the side to side and the trans is mostly sideways in the car volume wise.

    Just feel good you added 50,000 miles to the life of the trans.
     
  4. jdcollins5

    jdcollins5 Senior Member

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    The amount sounds right as I had about 1/4 of a quart left from the 4 quarts. The color of the fluid sounds just like mine, both at 25k and 50k miles.

    Now enjoy the peace of mind from knowing you have fresh fluid in the transaxle and have added life to your car.
     
  5. schorert

    schorert Member

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    Data? he can feel good, he just can't assume he's added even 1mile to the life of the trans.
     
  6. edthefox5

    edthefox5 Senior Member

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    I gave you data. I compared the color of trans fluid at same interval to a Ford truck trans. Ford truck trans was not half as dirty with wear metal in solution as my Prius was at same 25,000 interval. I have other data too in the Trans UOA sticky where I had my Redline fluid analyzed.
    Not sure why your such a downer. If you don't believe in maintenance that's fine but why talk other people out of taking good care of there cars. There's no waste I recycle all my fluids. Only costs me $40 every 3 years.
    Plus I get to analyze the fluid myself. If I change it and see metal particles or pieces of metal on the MAGNET on the end of the dump bolt I know the trans is going south and start looking around. Oh thats right. It has a magnet that traps all the metal particles. I guess if you don't service it and clean the magnet the magnet gets full of metal and will not trap anymore metal. At 25,000 there's quite a nice little pile of microfine metal on the end of the magnet.

    Your method I drive it till it fails.
     
  7. adamace1

    adamace1 Senior Member

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    56300 miles on it.
     
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  8. adamace1

    adamace1 Senior Member

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    I was one of the people that thought a drain and fill was a waste of money, but never seen suck gritty black fluid before. Now i feel alot better thats it's not low on fluid, and feel some better that there is fresh fluid in there.
     
  9. jdenenberg

    jdenenberg EE Professor

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    When you drain/refill it again in another 60k miles, it will look better.

    JeffD
     
  10. Batmobile 2010

    Batmobile 2010 Junior Member

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    How do you change the transaxel fluid? When filling up do I need to have the car running on ev mode? Or Neutral?
     
  11. schorert

    schorert Member

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    I'm a downer because you and others here make statements that are at least unverifiable and at worst outright falsehood. To state as a fact that changing the oil adds 50kmi to the life of a transaxle is pure speculation on your part. I agree that there MAY be a benefit to a fluid change, but to date I've seen absolutely no verification(nor will I). You and others here have identified what you believe to be a total oversight on the part of Toyota in their maintenance schedule. you make absolute statements that if owners want their transaxles to last this service is vital. It repeated here that if you DON'T do this service you don't "care" about your car and it will suffer an early death ( hence the condescending "Your method I[s?] drive it till it fails"). MY method is drive it, maintain it as recommended (unless there's a need to do otherwise) and sell it.
    Now, obviously you "care" more than I do about your car, and my car will suffer one of the increasingly common transaxle failures that plague these vehicles. um...wait a second...IS there a problem with transaxle failures? hmmm. I mean if you MUST change your TA fluid at 30kmi...and hundreds of thousands of owners are foolish enough to skip this(until 120kmi or beyond), these tansaxles must be burning up at a huge rate, right? no, they're not. So all you(the collective you, not you personally) have done is develop a completely unproven solution to a nonexistent problem.
    As to waste, well let's just say I "care" more than most. Beyond $40 per swap, there is an environmental expense to manufacturing, packaging, transporting, storing, transporting to your home, transporting back to place of purchase, transporting to recycling facility where your oil is processed, then shipped back out and burned as fuel. Now you multiply this expense by the number of board readers who you convince to perform this recreational maintenance...suddenly it's 200, 400, 1000quarts.
    It's time to acknowledge that all these recreational fluid swaps are more entertaining than they are "vital".
     
  12. ksstathead

    ksstathead Active Member

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    schorert, so when toyota's maintenance schedule requires one to inspect the transaxle fluid, that is just for grins and you skip it?
     
  13. hill

    hill High Fiber Member

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    there is a thread on PC - maintenance what you need what you don't . . . The Toyota hybrid specialist who wrote the article says the fluid will last a lot lot longer. Hmmmmm - wonder who I should I believe . . . . ;)

    SGH-I717R ? 2
     
  14. hlunde

    hlunde Member

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    This is really perplexing. There are no multiple disc clutch facings to wear in the Prius transaxle, so what are the "wear" particles. If it's gear wear something is seriously wrong. Issue should not be oxidation with Redline synthetic fluid. Are pigments leaching out of the motor dielectric materials?

    The fluid in my conventional (Aisn AW) automatic transmission is actually much clearer than what you show with 60,000 mile oil changes.
     
  15. jdenenberg

    jdenenberg EE Professor

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    The wear particles in my lab reports seem to be from the gears "Lapping in". Once the gears get smooth (break-in over the first 30k miles) the ATF stays clean longer.

    JeffD
     
  16. hlunde

    hlunde Member

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    Thanks! Was your fluid as dark as that shown by edthefox? And given the concentration of iron particles, can you estimate the total mass of iron particles that were in your transaxle, based on transaxle oil volume?
    It's still a mystery to me why the Prius transaxle is so hard on its lubricant. Gears are presumably helical which have only rolling contact, unlike the sliding contact in a hypoid gear pattern final drive. Bearings are of course ball or tapered roller where even very minor wear would quickly announce itself. And since many, and perhaps most Prius owners follow recommended maintenance and don't change their transaxle fluid, we should be hearing about frequent higher-mileage failures?
     
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  17. hill

    hill High Fiber Member

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  18. schorert

    schorert Member

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    well, lets think about this...if I take the car in for service and tell them to "inspect" the fluid, what are they going to do? are they going to do a UOA on it? they're going to check the level and nothing else! If they inspect it by wiping it on a towel, it's already well established here that the fluid is going to be black, agreed?
    So toyota techs routinely "inspect" fluid (that we all know is BLACK) and they DON'T change it! So the quality of the fluid in the TA is meaningless compared to the level of the fluid? Toyota knows the fluid is black...toyota knows the fluid (pan anyway) is full of crud, yet the despite that they don't recommend a swap for 120kmi and hundreds of thousands of the vehicles reach their full service life without anything but recommended maintenance.
    So yes, at 30kmi, I'm going to have them "inspect" it(check level). At 60k I might "inspect" it myself.
     
  19. ksstathead

    ksstathead Active Member

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    Toyota says cross the street. You cross the street. I go to crosswalk, look both ways, cross when safe. Both methods usually work.

    Why would I think the guys at the dealer who cannot torque a drain bolt, use the correct oil, or use the correct amount of oil have the first clue whether the fluid should be changed.

    Toyota does not recommend changing the fluid ever. Not at 120,000 miles, not ever. Inspection of fluid has a plain meaning different from checking the fluid level. Changing at 30,000 miles is 0.1 cents per mile. Then at 60,000 it is 0.05 cents per mile. I'd rather have fresh fluid even if there are no cars likely to hit me if I just cross the street. I'll go with what the UOA's have indicated. I do not believe Toyota has invented magic fairy fluid that never wears out, yet do not proclaim the acheivement.

    To each his/her own.
     
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  20. jdenenberg

    jdenenberg EE Professor

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    The first drain (at 61k miles) was quite dark, but the two following ones (at 120k and 180k miles respectively) were still red - just a bit darker than the virgin Type WS ATF. It may be interesting to pull a sample from a new - fresh from the factory - Prius and do a lab analysis. I'll do that when I next buy a new Prius (which may be soon as our 2001 Jetta auto transmission is showing weakness - hesitates to go into reverse - note that VW also doesn't suggest drain/refills of their ATF, but then again VWs aren't very reliable cars and the VW parts guy admits that their Auto transmissions are weak)

    Just to add some data to this discussion I've attached the ATF lab analyses I've done to date.

    JeffD
     

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