Down Shift Linkage

Discussion in 'Transmissions' started by Columbus Comet, Mar 10, 2007.

  1. Columbus Comet

    Columbus Comet Member

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    Can you run C4 without downshift linkage. It's a stock tranny. Replaced carb and intake with eldebrock performer and couldn't figure how to hook it up.
  2. don graham

    don graham Member

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    i don't have any on mine. it's a track only car. but, i would think it's the same principle. if i want to go faster i just give it more gas.:)
  3. ford84stepside

    ford84stepside Lone Wolf

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    I've ran my 84 pickup without a kickdown linkage for years. Matter of fact, I took it loose because when it downshifted, it would actually slow down instead of going faster! I think it is a C6, but still the same deal as a C4. You can always manually downshift it with the shifter if you needed to.
  4. Mavaholic

    Mavaholic Growing older but not up!

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    Its only used for kicking down a gear for passing. You can do the same thing by pulling the shift lever down. Will work just fine without it.
  5. Craig Selvey

    Craig Selvey Indiana State Rep - MCCI Supporting Member

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    If you have an edlebrock carb....you just need to buy the linkage for the kickdown.
  6. Columbus Comet

    Columbus Comet Member

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  7. PaulS

    PaulS Member extrordiare

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    Yep, it'll run "fine" without the kick-down linkage but it won't run right.
    On the street you can have problems with double shifts going to high and soft down shift from 3 to 2.
    Most of the time it all seems fine and unless you had a gauge on it you won't notice the damage being done. Let's face it - if it ran right without the linkage Ford would save the millions of dollars it spends (spent) installing and adjusting them.
  8. Mavaholic

    Mavaholic Growing older but not up!

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    Thats BS. It will run fine without it and it will not do any damage.
  9. Blown 5.0

    Blown 5.0 Hooked on BOOST MEMBER

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    The downshift linkage is actually a line pressure booster, You can run without it BUT with a lot of power or a worn trans you may slip clutches, FORD did put it there for a purpose. I do run the linkage on mine, its only triggered a wide open throttle. Lockar makes the linkage just for a C4.
  10. PaulS

    PaulS Member extrordiare

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    Thanks for the input Blown 5.0.
    Its good to see that there are people who understand the inner workings of the tranny.
    Manually shifting also increases the line pressure too. So if you always shift manually then you have no need for the kick-down leveror valve.
    Paul
  11. Columbus Comet

    Columbus Comet Member

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    Thanks for information. Maybe I'll check into the locar cable.
  12. blugene

    blugene Senior member Supporting Member

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    I am installing one of these cause I have an automatic and would like to use that function when not in challange mode...LOL!
  13. Phyphor1

    Phyphor1 Member

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    Yea, you can run w/o the passing gear linkup. But you'll have to drop to 2nd manually if you want to kick it down from high! ;)
  14. PaulS

    PaulS Member extrordiare

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    The problem of running without the "downshift" linkage working is that you never get the increase inpressure until you move the lever manually. Every time you go up a hill the transmision needs a boost in throttle pressure to keep the clutches from slipping a bit. every time you start to press down on the gas pedal at low speeds you are adding torque to the tranny from the engine without adding any pressure to the tranny. The modulator will add some pressure but it is nothing like the Kick-down.
    Now if you are running a full manual valve or have boosted the pressure with a super spring in the pressure regulator then you have enough pressure that you don't need the added pressure of the "kick-down" valve. On the other hand, if you are running a pure stock tranny then you are going to hurt the tranny and it will fail. Usually the forward clutches will fail first and they are followed by the direct clutches.
    From my point of view you would be better off not running vacuum to the modulator - at least THAT will ADD pressure and not take it away. (don't do it - your tranny will shift very hard under decelleration and it will shift very late in a mushy sort of shift without the Kick-down linkage hooked up. Give your transmission a break and let it work right so it will live a long and satisfying life, bringing pleasure to the driver and reigning discomfort on the passengers.
  15. broncoisl

    broncoisl Member

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    Should this be a cable or a rod? It's missing from my car.
  16. PaulS

    PaulS Member extrordiare

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    Cable or rod? Ford had rods that connected from the throttle lever to the linkage at the tranny. Lokar makes a cable kit that has the proper bracketry to make it work.
  17. Craig Selvey

    Craig Selvey Indiana State Rep - MCCI Supporting Member

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    Paul:

    Is a "spring" required on the kick down lever? I have seen some cars with a helper "spring" and some without.
  18. dkstuck

    dkstuck New Member Supporting Member

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    Agree with PaulS 100% on this! Lokar cable works great
  19. hotrod-daddy

    hotrod-daddy Member

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    I too go with LOKAR (y)
  20. blugene

    blugene Senior member Supporting Member

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    The "bracketry" is extra...but not too much, I think like $20 or under.
    Unless you have a show quality car I wouldn't spend the cash on the polished stuff, it doesn't look much different.

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