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Vibration/noise when accelerating after both cv replacement and trans fluid change

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Tyler Wrage, Apr 29, 2022.

  1. Tyler Wrage

    Tyler Wrage Junior Member

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    Hi all, I just replaced both of my CVs and did a trans fluid change on my 07 w/200k and now have a vibration/noise when accelerating. I live rurally so ended up using 4qts of Maxlife trans fluid (time crunch to get the car fixed, no Toyota dealer within about an hour and couldn't get WS in time - I understand it's a hot topic) and replaced both my CVs with new NAPA axles, as both had torn outer boots - throwing grease everywhere and slowly creating a shake.

    I suspect my new issue is related to the CVs, as right when I installed them I could hear the whirring/humming of them from like 30-40mph before it finally smoothed out in my initial test drive. The CV shake I had before replacement is gone. Now, when I apply a fair bit of gas (enough to get the engine to rev up to ~3000rpm, you all know how engine speed will flare up when applying roughly half throttle), I get a strange vibration that I can feel in the floorboard and faintly in the steering wheel with more noise than I had before. The car also feels slightly more sluggish than it did, but that may have been due to the battery being down to 2 bars from sitting too, not sure.

    The drain plug of the trans did have a small buildup of black sludge (which from my understanding is pretty common?), with only one tiny visible metal flake in it, so I don't think I have to worry about the trans being destroyed unless something has gone horribly wrong along this process somehow. I am a fairly good home mechanic, but have only basic knowledge of the Prius trans. It's my understanding that it's more or less a sump/submersion setup - I had to fill the trans with the passenger side in the air to fit under it (filled after installing passenger CV) and got four quarts in without it running out, but figure it has to be right at the top and properly full, per spec. Axles torqued to their spec as well.

    I did notice that when removing the old CVs, the trans wiggled a bit when tapping the axles out - perhaps slightly worn mounts, maybe part of the culprit as well? The trans fluid really looked pretty good, still quite red - I have only owned the car for a year so decided I should change the trans fluid just to be safe given its mileage, and now I am questioning why I bothered doing anything in the first place.

    After doing the driver CV I lost close to a quart of ATF, so decided to do the other CV and replace the fluid - I got basically four quarts out (hard to say with the first quart dumping all over the floor) and put four in. Just looking for some confirmation that I am not completely destroying my transmission driving it the next little while with the noise/vibration under accel I guess, and that the (pic related) material that was on my drain plug is nothing to be horribly concerned about.

    I know ideally there would be nothing on the magnet, but don't think the sludgy crap is life-ending(?). Hoping that if it is the CVs, they will fling their grease around inside the boots enough to even/balance out and resolve the odd vibration/noise I am experiencing as time goes on and I won't have to worry about replacing them again.

    I am open to getting WS trans fluid in the next few weeks when I can get some if for whatever reason the new Maxlife could be causing issues and you truly think the sound can be attributed to that, but I wouldn't think I would see an immediate additional noise/vibration/difference in performance, given it is at least incredibly close to adequate and at least filled properly. Appreciate any ideas that you might have. Thanks!
     

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    #1 Tyler Wrage, Apr 29, 2022
    Last edited: Apr 29, 2022
  2. JC91006

    JC91006 Senior Member

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    Most likely sound not caused by transaxle. You have to inspect further, maybe other suspension parts need attention?

    The sluggishness is from the hybrid battery down to 2 bars, you would need to be above 4 bars to lose the sluggishness.

    I would recommend using WS fluid if you can get your hands on it.
     
  3. Tyler Wrage

    Tyler Wrage Junior Member

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    thanks for the reply. I replaced all four struts, one ball joint, one wheel bearing, and one sway bar end link since I have owned it, pretty much all within the last 6 months or so (and now CVs), as well as had the car aligned after the struts/ball joint, the most recent repair. Did a pretty decent check over when I had to take stuff apart to swap the axles, and aside from being covered with axle grease, all looked good.

    I drove the car about 10 miles today, enough time for the battery to get back to its normal state, and something just seemed a bit off about how it drove. I'm not sure if I was just looking for something to be wrong, but the vibration/noise on acceleration is my main worry. I had to get pretty rude with the drivers side CV to get it out, and the transmission probably had a half inch of play back and forth as I applied force to remove the CV.

    After typing this out, I wonder if that bit of movement caused my small manifold/cat leak (reused donut when swapped cat) to increase, resulting in more of a resonance/vibration when accelerating, hmm... I may go drive around a bit tomorrow and see if I can detect anything else that might point me in the right direction, still leaning toward the CVs being the culprit (or contributors) due to the first test drive noises at 30-40mph, just seemed subpar to me right off the bat.

    Good to know the trans isn't likely the root of the problem, hopefully the drain plug sludge wasn't too scary. Will try to get some WS within the next couple weeks, especially if I can't find the noise before then. Much appreciated, and any other thoughts are always appreciated!
     
    #3 Tyler Wrage, Apr 29, 2022
    Last edited: Apr 29, 2022
  4. mr_guy_mann

    mr_guy_mann Senior Member

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    Please, use the return key here and there to create paragraphs. Trying to read one single huge post without breaks in it is chore.

    Now, if you put replacement axles in the car and get vibes on accel that weren't there before, then you most likely have a bad inner joint on one of them. Especially if they are reman.

    When you do axles, give the axle seals in the transmission a close inspection. Also check under the car for any leakage a week or two after doing the work. Sometimes a seal can get hurt during axle replacement and that might not be obvious.

    Posted via the PriusChat mobile app.
     
    Mendel Leisk likes this.
  5. Tyler Wrage

    Tyler Wrage Junior Member

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    Noted on the formatting, was using my phone which admittedly isn't the best option, the mobile site was a bit wonky and I didn't think to go back and format the posts, my bad. Went through and did a rough edit to make the post more readable.

    The CVs are new, not reman, from NAPA. Aside from checking for side to side movement in the inner joint, what else is there to do to to determine they are the culprit? They seemed tight and of pretty good quality when I installed them, but might drive it up on ramps and check the inner joints for movement, thanks for that thought. Unfortunately it's rainy and miserable today, but hopefully will get a break in the weather to do so.

    Axle seals looked good, I had one super tiny tear on the passenger side, but it wasn't on the actual sealing surface, simply on the furthest out part that basically does not seal anything. Figured I would keep an eye out for a drip or two, but am sure that won't be an issue.

    I'm glad it's looking like the general consensus is that it is axle related rather than something weird transmission wise, I can deal with having to rip an axle out again if one of them proves to be the culprit.