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Transmission leak or oil or? Photos... Please help

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by FriedCells, Jan 31, 2022.

  1. FriedCells

    FriedCells Member

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    IMG_20220131_134406__01.jpg I have a very fast leak. It's sprayed all under my car. I just can't figure out what fluid it is. I've been researching, but can't find an answer. It looks like oil on the ground. Dark. But when I get it on a towel, it looks like it might have a hint of red in it. Could just be old tranny fluid. It's between the engine and transmission, near the tranny drain plugs and coolant drain plugs, just below a black plastic cover. It's leaking around the bolt in the photo (it's tight) and an indent where there's a seal for this part. My oil level does get lower but it's been burning oil anyways for a while. 2011 with 173,000 miles. I'm assuming it's transmission fluid but does anybody know for sure what leaks from this spot and what the fix is? Thank you so much! IMG_20220131_134358__01.jpg
     
  2. PriusCamper

    PriusCamper Senior Member

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    What does "fast leak" mean? Checking oil level on Transmission fluid is next step if you're certain it's not coolant...
     
  3. FriedCells

    FriedCells Member

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    While it's running, you can see a drop every 3-5 seconds. It's definitely not coolant. I know where the transmission fill hole is but checking the level of fluid, not sure how. Stick something in the hole and see how far it goes before wet? Or is there an easier method?
     
  4. jzchen

    jzchen Newbie!

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    If you can purchase some transmission fluid. Open the fill hole. Try to add some. IF it doesn't immediately start dripping out it's probably transmission fluid leaking. The fill hole is at the full level as I understand...

    REVVL V+ 5G ?
     
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  5. tankyuong

    tankyuong Senior Member

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    Just sniff the fluid to determine
     
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  6. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    ^agreed. If you already know what ATF and motor oil smell like, this will take 30 seconds to solve. But if you don't know what they should smell like, it doesn't do any good.

    There is no ATF pump in a Prius. The fluid is not pressurized or moved around other than displacement of the gear/MG assemblies.

    However there is an engine oil pump. When the engine runs, some of the oil is pressurized and pumped through the engine, eventually returning to the sump.

    If the leak changes rate when the engine is running, I think you're dealing with an engine oil leak.
     
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  7. PriusCamper

    PriusCamper Senior Member

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    Stick a finger in it or some other object... Proper trans fluid level is bottom edge of that hole. Hopefully it's as simple as accessible bolts that got loose and you can fix it by tightening them. If not, next step is to monitor the rate of loss and keep it topped off and start saving up for repair. If I were you and if I could afford it, I'd use it as excuse to replace with a low mileage Gen 4 engine so you don't have to worry about the known issue of early Gen 3 blowing head gaskets, as well as burning oil.
     
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  8. JC91006

    JC91006 Senior Member

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    a drop every 3 to 5 seconds.....can this be from your AC?

    I can't imagine oil or transmission fluid leaking under your car, it just looks really clean. If there's a persistent leak, the undercarriage of your car would be caked with this oil.
     
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  9. edthefox5

    edthefox5 Senior Member

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    It’s trans fluid I can see the red. If it was me I would get a can of carb cleaner and hose the suspected are off so it’s clean. Take more pics. Do you have the iPhone photo magnifier app that would really help.

    you sure it’s not leaking out of the seal where the cvt axle enters the trans
    And running down to this bolt area? That’s a common leak area if the cvt axle not installed well or damaged.

    very rare to have a trans leak there at that bolt.

    I wonder if the engine was replaced?

    Have you tried tightening the bolt? I would use a 1/2 in ratchet. It’s a big bolt
    Pretty high torque.

    What’s your ownership history with this car?
     
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  10. FriedCells

    FriedCells Member

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    I cleaned it up to locate the leak. It was everywhere, all the way down the middle of the car, on the cat, muffler, everywhere. It's been spreading/spraying all over the place. AC drips clear water only, this is dark oily stuff. After looking again, my oil is fairly light/new in color. The drops are much darker. It must be transmission fluid.
     
  11. bisco

    bisco cookie crumbler

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    maybe the fill plug fell out.
     
  12. JC91006

    JC91006 Senior Member

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    If it’s dripping at a fast rate, you should be losing lots of oil. If your oil dipstick level still shows full, then it’s transmission fluid. There is no dipstick for that.

    one of the more common areas for transmission oil leak would be from the axle seals, particularly the driver’s side seal.
     
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  13. FriedCells

    FriedCells Member

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    Thank you so much for the reply. I checked again today and no leak from the cvt axle. It is definitely coming from that bolt area. I watched it while engine running and it comes straight out of the bolt hole from around the bolt and also in that area. Bolt is super tight though. I also noticed it seeping from behind a plate (see photo with red circle). Can't see the fluid now but I cleaned it off, then watched it seep around the bottom of that plate. It is certainly reddish in color as well. My oil is light/recently changed. The drops are much darker than my oil. Need to get the right tool to open the transmission drain though to check the level.
    IMG_20220202_152033__01.jpg IMG_20220202_144709.jpg
     

    Attached Files:

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  14. FriedCells

    FriedCells Member

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    Thanks everybody for your replies. Some new photos and info in the post above. I need to get the tool to open the transmission drain hole. Surprised I don't have it already as I drained the coolant in the past which has the same plug... but cant find it. Anyways, definitely seems to be transmission, but can't find any info online as to what would cause such a leak in those areas.
     
  15. FriedCells

    FriedCells Member

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    Nah, it's there. You can see it in the photos.
     
  16. FriedCells

    FriedCells Member

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    Thanks. Yeah, oil is pretty steady. Burns a little bit but it's not dropping as fast as the leak. Looked at it today again. New photos in a post above. Is not leaking around the axle seals though. Shined a light on it while it was running and it's dry there. Just dripping straight around the bottom bolt area,, right around the head of the bolt but also generally through the cracks in the housing there.
     
  17. TMR-JWAP

    TMR-JWAP Senior Member

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    When I've changed the fluid in my Gen 2 transaxle, I normally see a bit of vacuum when I remove the plug. You can hear it. I wonder if the vent on your transaxle is clogged/stuck and you're experiencing a pressure buildup in your transaxle, which is pushing fluid out of the front seal or something similar
     
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  18. edthefox5

    edthefox5 Senior Member

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    Hey Fried that plate is an inspection plate for what usually is the flywheel in a car but in this car its a clutch throwout like plate with dampening springs to dampen and smooth out the trans/engine connection. Just to remove the engagement shock of the trans powering the engine. There is no harm to take that plate off with its 2 bolts and do a look see in there.
    Very interesting issue have not seen that on this site before. if its leaking out of that plate area that's crazy. And the trans has failed.

    Whats the deal with this car is it used or is it a salvage title, or did you buy it new? Was the engine replaced they usually replace the engine/trans as a unit.

    If used run a carfax on it. See what your up against.
     
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  19. FriedCells

    FriedCells Member

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    Thanks for the info. Really appreciate that. I'll check it when I get the tool to open the plug for any vacuum. If there isn't vacuum, any idea where and how to unclog the vent? Thanks again.
     
  20. FriedCells

    FriedCells Member

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    I will check behind that plate as suggested. Thanks for all the advice. I have a borescope that I can send through there to get a good look. Sorry, I forgot to answer the questions about car history from your previous post. I'm the 2nd owner. I bought it when it had 50k miles on it. It was immaculate at the time, Carfax showed no damage, and impeccable maintenance records. Now has 173K miles. No accidents or damage since I've owned it. Thanks again for all ideas. Won't be able to work on the car until Monday though. Leaving tomorrow for an anniversary getaway. Not in the Prius though That would be a bad idea.
     
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