Severe Vibration at Low RPM on 2020 Cascadia DD15 – Need Help

Discussion in 'Heavy Duty Diesel Truck Mechanics Forum' started by Cihanakbaba, Jul 4, 2025.

  1. Cihanakbaba

    Cihanakbaba Bobtail Member

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    It’an automatic transmission. Did you have had the same issue before?
     
  2. ElmerFudpucker

    ElmerFudpucker Road Train Member

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    I have seen clutches cause problems before. Does it have a clutch pedal, because you said the problem stopped when you disengaged the clutch.
     
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  3. Cihanakbaba

    Cihanakbaba Bobtail Member

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    no it’s an automatic transmission doesn’t have any clutch pedal. But when Truck goes neutral it shakes more
     
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  4. blairandgretchen

    blairandgretchen Road Train Member

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    Get the story straight please.


    IMG_9780.jpeg
     
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  5. Cihanakbaba

    Cihanakbaba Bobtail Member

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    OK. There is no clutch pedal. It’s an automatic transmission. But you can still shift the gears manually.
     
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  6. ElmerFudpucker

    ElmerFudpucker Road Train Member

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    I have no experience with automatics. Is it automatic or auto shift? I’m sorry but, but the quality of your replies will depend on the accuracy of the information you supply
     
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  7. Cihanakbaba

    Cihanakbaba Bobtail Member

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    Thank you for your time. It’s not related with transmission
     
  8. blairandgretchen

    blairandgretchen Road Train Member

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    I’ll second @ElmerFudpucker comments. Have no experience with automatic transmission trucks.

    You’re just lucky there’s a bunch of truckers enjoying some form of a holiday weekend, disinterested enough to respond.

    Are you sure the driveline is intact - like - “Get on a creeper with a bar and wiggle stuff around?”

    Or are you just relying on your mechanics advice?
     
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  9. Ridgeline

    Ridgeline Road Train Member

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    Yes, a couple times.
     
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  10. ElmerFudpucker

    ElmerFudpucker Road Train Member

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    Then it sounds like you have it under control. Have a nice day.
     
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