Meritor 12 speed auto

Discussion in 'Trucks [ Eighteen Wheelers ]' started by Koerbs, Aug 10, 2009.

  1. Koerbs

    Koerbs Bobtail Member

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    I am looking at buying a truck with 611,000 miles with a meritor 12 speed auto. I have never driven or heard much about auto transmission semi's.

    It is a 9400i ISX 400

    So, what is the life span of these transmissions? How much is a replacement unit?

    Thanks!!!
    :biggrin_25525:
     
  2. stranger

    stranger Road Train Member

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    I don't know about the lifespan, but I did drive for a company that had several. They are smooth shifting, and the extra two gears are nice.

    However, the Meritor does NOT float the gears like the Eaton does. This means the clutch is depressed with each shift, wearing all releated parts with each shift. The company I was at used them behind C-13s, and experienced chrankshaft thrust bearing wear out in a short amount of miles using this transmission.

    Now, I have heard that the C-13 is known for thrust bearing problems, but the conanstant clutch useage made this much worse. The thrust bearing problem without a Meritor is a rumor, but the problems the company I worked for had using the Meritor were real.

    That's all I know. Hope it helps.
     
    Baack Thanks this.
  3. Koerbs

    Koerbs Bobtail Member

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    I don't see a clutch pedal.....
     
  4. Koerbs

    Koerbs Bobtail Member

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  5. stranger

    stranger Road Train Member

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    The transmission clutches itself with an air operated slave cylinder. It's a two pedal fully automatic operation.

    I sometimes had to stop and restart the truck to get the Meritor to reset itself after it would lose its mind every so often when using it manually.
     
  6. FYDA FREIGHTLINER CINCY

    FYDA FREIGHTLINER CINCY Light Load Member

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    i would put money on it that the clutch has been replaced once already, if u can get them to print off the clutch abuse info, scan it and post it on here. i will be able to tell u if the clutch is good or not. thats the biggest problem with those trans is the clutch. when u test drive make sure it shifts, takes off from a stop and comes to a stop smooth.
     
  7. cat from the valley

    cat from the valley Medium Load Member

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  8. TURKER

    TURKER Medium Load Member

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    Because the auto trans. I and Many drivers dont like them!