c4 problems

Discussion in 'Transmissions' started by chromed302, Jan 6, 2014.

  1. chromed302

    chromed302 Member

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    c4 upshift problems

    Hopefully someone can help me out, I have a 77 c4 case filled green stripe modulator and what its doing is... I can put it in park, neutral, reverse and drive and it does just fine but when I put it in drive its stuck in low gear(1st) and doesn't shift and it wont shift manually from 1st to 2nd to drive just stays in that low gear(1st) I been told to check governor and vacuum modulator and the psi on it I put a new modulator in it and I have it running to a vacuum tree on my intake and the valves in the governor move freely what else I can check out? Thanks!
     
    Last edited: Jan 6, 2014
  2. 71gold

    71gold Frank Cooper Supporting Member

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    is the...kick down rod...moving freely/hooked up?
     
  3. chromed302

    chromed302 Member

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    I'm not running the kick down i hear some say its not really useful you can use it if you want if not it wont hurt anything?
     
  4. Maverocket

    Maverocket Bob Williams

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    When installing the valve body it is possible to get the kickdown lever in the wrong position causing this problem. The lever outside the trans could be bound up on something in the applied position.
     
  5. chromed302

    chromed302 Member

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    well right now I have it tore down I took tail shaft off and took off the governor to check the valves make sure they weren't stuck then I took vb out to check make sure maybe the 1-2 shift valves weren't stuck(haven't been able to take vb apart to check that yet) I've been reading articles about this would the forward clutch spring or the parking pawl have anything to do with my problem?
     

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