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Is my transmission going out?

Discussion in 'Tech Discussion' started by thecantaloupeman, Nov 8, 2019.

  1. thecantaloupeman

    thecantaloupeman Full Access Member

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    So this morning I drove to work and in the first intersection I was flooring the gas pedal and the car was accelerating extremely slow. It felt like maybe a transmission problem. At one point it even sounded like it would stall even though the pedal was floored.
    This isn’t the same problem with the accelerator pump I was having, but it just felt like the engine was making no power or something.

    I changed to neutral and back to drive and it seemed to get better. Then I had to do a three point turn and changing from reverse to drive seemed to make the problem go away. Why is this? Could this just be a cold weather problem?

    I’m really hoping it’s not the tranny going out. My heart would break. I have heard these turbo 400s are built like tanks so I have no idea. Anyone have some insight?


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  2. Arkansas_V8

    Arkansas_V8 Proud Redneck

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    First thing to check is fluid level.
     
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  3. varmit86

    varmit86 Full Access Member

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    Sounds like maybe there is some crap in the fluid, if the very small passages get clogged well need I say more.
    When you switch gears it changes the fluid flow and then back, this could move the crap along. Plus the fluid it thicker when it is cold compounding the problem.
    I would try a trans flush with new filter and see if it goes away.
    It is fairly cheap 1st shot

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  4. Big Chip

    Big Chip Full Access Member

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    Yes
     
  5. Snoots

    Snoots Supporting Member Supporting Member

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    Parking brake on?



    Sorry. I couldn't resist ;-)
     
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  6. JoeR Jr

    JoeR Jr Full Access Member

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    When the gas was floored, was the engine revving up like it was in neutral? If so, it sounds like the trans is slipping. If the engine is bogging, and not revving way up with it floored, it's pretty unlikely it's unlikely that there's a problem with the trans.
    Joe
     
  7. 80BrownK10

    80BrownK10 Full Access Member

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    Yes like mentioned check trans fluid, with truck running on level ground warmed up.

    And like Joe said if the engine doesn't rev up like your in neutral , there may be something else? Cause that's what it sounds and feels like engine reving way up and your barely moving for the engine speed. If engine is bogging it still could be some sort of mechanical damage, in the driveline somewhere but not a normal transmission slipping behavior.
     
  8. 1987 GMC Jimmy

    1987 GMC Jimmy Automobile Hoarder

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    I know you’ll elaborate in a little bit, but it sounds like the engine is giving you grief because you’re talking about stalling with the foot to the floor. Almost like you’re getting too much air or fuel and not enough spark. As mentioned, the trans slipping would sound like the RPM wasn’t proportional to the driving output of the vehicle. If the transmission does end up being the culprit, I would check the fluid level, and if still nothing, pull the pan and inspect the fluid, pan magnet, and cut open the filter. Then service it with fresh Dex III/VI and a quart of Lucas transmission stuff.

    I used to be paranoid about my transmission going out on me. I’ve since found out that even the best transmissions can break, and as far as the worst ones go, even a stopped watch is right twice a day, and you may very well have one of the good ones. You just take care of them the best you can until the day comes.

    One more thing, give yourself time to let it warm up if you haven’t been doing so. We drive the piss out of newer cars from minute one, and I don’t really care about them one way or the other, but an older vehicle really benefits from building a little heat in order to let the fuel atomize better, the oil liquify some, get up to the top end, and then let the transmission fluid warm up as well and not strain old parts by trying to push fluids with the consistency of molasses through.
     
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  9. thecantaloupeman

    thecantaloupeman Full Access Member

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    No I guess it was more of a bog. It sounded like it wanted to stall. Could it have been in second gear for some reason? That would sorta explain why it took so long to accelerate and was fine once up to speed. I do know the fluid is dirty because it was tested and is black. But I don’t know if I’ll be able to identify the cause of the problem unless it happens again. I drove it around some more after I had the problem and it seems to have gone away.

    This kind of thing is the stuff that really bothers me because you never know when something could fail and you’ll be stuck. I can’t even predict what the cause is. Guess I’ll just say a prayer and maybe flush the fluid myself. There’s only so much you can do.


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  10. Arkansas_V8

    Arkansas_V8 Proud Redneck

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    Nasty fluid would be a problem.

    You wouldn't leave that in the oil pan, so you can't leave it in the transmission pan.
     
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  11. gmbellew

    gmbellew Member

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    Could be a sudden onset vacuum leak. I had an intake manifold leak once and it seemed like the engine would want to stall and wouldn't make power at idle or low speed. But it would run down the highway like a champ.
     
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  12. Dmack

    Dmack Full Access Member

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    Choke stuck on?
     
  13. gotyourgoat

    gotyourgoat Full Access Member

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    So can you clarify how the trans fluid was tested? And black? Major color changes in trans fluid color would be from excessive age, excessive heat, or particulate in the fluid. The heat and particulate being the worst.

    Also not sure the engine and trans issues are entirely related.
     
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  14. 80BrownK10

    80BrownK10 Full Access Member

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    If the fluid is black you need to change it. May be too late. But I would drop the pan and replace filter and look at the metal on your magnet in the pan. Fill it with new fluid. If you want to get all fresh fluid and not just what's in the pan, get a few buckets and let it pump new out of one and the old into another. You can find a video of it on YouTube. It really will just involve some hose clamps and several feet for each line of 3/8 fuel hose to extend the lines from where you take them loose on the radiator to some buckets on the ground.
     
  15. JoeR Jr

    JoeR Jr Full Access Member

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    It's certainly possible that it stuck in 2nd or 3rd, but it's not likely. It's also possible that the converter failed, but it's almost impossible for it to fail intermittently. My money is on an engine problem. Not trans.
    Joe
     

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