1965 904 Transmission Normal Operation?

Transmission and Drivetrain Tech

  1. barracuda1965

    barracuda1965 Barracuda1965 Formula S

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    I've had my 65 Barracuda Formula S together and running for a number of years now but still wonder if the transmission operation is normal. It is a stock 65 904 cable shift trans that shifts normally except for down shifts. It will not downshift from 3rd to 2nd gear under part throttle. It will drop all the was to 1st when floored. First off I have adjusted the kickdown to stock specification and fine tuned it up and down.. changes nothing. It will manually shift to 2nd with the floor shift.
    Somewhere I remember reading that this transmission does not downshift to second by design. True or false?
     
  2. 65 Dartman

    65 Dartman FABO Gold Member FABO Gold Member

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    I believe that part throttle operation was not adopted until 71 or so. I don’t think it can be adapted in these earlier transmissions.
     
    Last edited: Jun 17, 2019
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    • Charrlie_S

      Charrlie_S Well-Known Member

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      It does not have part throttle downshift, but it should still downshift from 3rd to 2nd at full throttle above a certain speed, or 2nd to 1st at a slower speed.
      As for retrofitting part throttle downshift, I know it can be done on 66 and later transmissions, but don't know if it can be done on the cable shift trans.
       
    • challenger57

      challenger57 cuda57

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    • challenger57

      challenger57 cuda57

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      I had a cable shift in my 65 also before changing to a 4sd manual. If left in drive it shifted normal, i don't ever remember it down shifting to a lower gear while other than the gear i had it in. I still have it if any interest.
       
    • dibbons

      dibbons FABO Gold Member FABO Gold Member

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      Can'y verify accuracy, but here it is from Wiki:

      In 1968, part-throttle downshift functionality was added to A-904 transmissions used with 6-cylinder engines. This feature permitted the transmission to shift from third to second gear in response to moderate accelerator pressure. Previously, an automatic 3-2 downshift occurred only if the driver pushed the accelerator to the floor. This change was made to maintain acceptable in-town performance with taller final-drive ratios in the rear axle — 2.76:1 rear axle gears were being furnished in applications previously equipped with 2.93:1 or 3.23:1 gearsets. Part-throttle downshift functionality was extended to V8 A-904s in 1969, and to most A-727 transmissions in 1970 to 1971.

      I have driven my parent's new 1971 Road Runner and I own a '65 Signet Convetilble and '65 Formula S all automatics. I tend to agree with the Wiki article based on my personal experience.
       
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