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    kickdown feature is broken?

    Hey!

    I rebuilt a transmission --with the help of a professional-- for my 1990 colony park wagon.
    It's an AOD with several internals from an AODE for the 2" OD band, and mechanical diode reverse drum (what the OD band rides on), A++ OD servo, and a slightly higher rpm torque converter.
    It also turns out it's the longer tailshaft version (oops). Guess it didn't come from a mustang like the guy told me.

    Anywho.

    Installed it tonight, with a properly fitting driveshaft, and took it for a spin.

    The shifts are at higher rpms, but, that's what I wanted. Maybe 2000rpm for 1-2 and 2-3.
    If you feather it, it shifts nicely. Upshifts are a bit delayed versus what it used to be.

    So far so good.

    However, if you add a bit of gas, it wants to downshift quite prematurely. Seriously; if you are not feathering the gas pedal, any bit more pressure, it tries to downshift.
    And when it does try to, it fails. The engine revs to 3 grand while the car feels like it must be in neutral.

    So something's up with the kickdown cable.
    Of course, I messed with everything around the transmission. If you can adjust the kickdown cable at the transmission, then, it's possible I didn't resecure it in the same place. Or maybe the amount of tension that worked for my old AOD doesn't work for this one, with the higher stall converter, and, possibly, the higher rev regulator-- though I'm not certain of that.
    But it bothers me that not only does it try to downshift very easily, but it doesn't succeed in downshifting anyway.

    Thoughts on what might need adjusting and how?
    That's my hope, anyway.

    My fear is that there's something internal I screwed up.

    But I was getting these shift flares both in 2-3 and 3-4, corresponding with trying to accelerate a little harder. It doesn't feel like it's just one gear that's not holding, but, specifically when I give it more gas and it feels like it's trying to downshift.

    #2
    I guess, the tv cable is probably waaay off.
    But why would it have worked for my old transmission, and be so far off for the new one?
    Is there something down at the transmission end that could affect tv pressure?

    Comment


      #3
      What transmission TV lever did you use? The one for your 90? I'm talking about transmission side, where the cable attaches.

      Comment


        #4
        Yes, I swapped it over. The one on the transmission was presumably for a mustang, and completely wrong.

        Comment


          #5
          Went to my friendly neighborhood transmission shop and figured it out.
          I still want to re-adjust my tv cable,
          but the real problem is that overdrive slips. I just wasn't attuned enough to realize that the flaring was the transmission popping out of overdrive and overdrive only, and as for why it was doing it when I gave it extra gas, that was extra torque that broke the drum free of the too-lightly clamped OD band. So that's why very light acceleration seemed to work better.

          The near-certain cause is that A++ OD servo that I installed.
          I had to grind down the pin as per the instructions, to fit a gauge that was included with the kit.
          To make it fit like they said, I ground off a lot. It didn't seem right.
          And obviously, it wasn't right, because it doesn't clamp the OD band tightly enough to hold.

          I'm going to have to order a new OD servo pin, and figure out what I need to do, to get it right.
          Luckily this doesn't even involve removing the transmission, let alone tearing it down; just drop the pan, drop the valve body, and there's the servo.
          In the meantime while waiting for the new pin, I can likely just put it in Drive instead of Overdrive, to safely use my grand marquis again without damaging the new transmission.

          Comment


            #6
            bah. that's all I have to say about that.

            Only two things are infinite, the universe and human stupidity, and I'm not sure about the former. -- Albert Einstein
            rides: 93 Crown Vic LX (The Red Velvet Cake), 2000 Crown Vic base model (Sandy), 2003 Expedition (the vacation beast)
            Originally posted by gadget73
            ... and it should all work like magic and unicorns and stuff.
            Originally posted by dmccaig
            Overhead, some poor bastards are flying in airplanes.

            Comment


              #7
              Glad you got it figured out, & were wise enough to get it troubleshot? troubleshooted? by professionals before you did any damage!
              ,
              Slicktop '91 GS HO 4.30 rear. '82 Mark VI Tudor HO, '90 F-150 XLT, '62 project Heep, '89 Arizona Waggin' and '88 donor in PA, getting combined.

              Comment


                #8
                I'm trying to become one of those! [a professional], but unfortunately, it's only through troubles like this that one gains the experience

                adjusting my tv cable now; turns out my cable was loose all these past thousands of miles. Oops!
                But while it will make for more line pressure, I doubt that it will be quite enough to help the overdrive.

                Comment


                  #9
                  Originally posted by BerniniCaCO3 View Post
                  I'm trying to become one of those! [a professional], but unfortunately, it's only through troubles like this that one gains the experience

                  adjusting my tv cable now; turns out my cable was loose all these past thousands of miles. Oops!
                  But while it will make for more line pressure, I doubt that it will be quite enough to help the overdrive.
                  i tend to leave the trans in drive until about 60-65 or so
                  89 townie, mild exhuast up grades, soon to have loud ass stereo....

                  Comment


                    #10
                    hey by the way, how much damage am I likely to have done, slipping the overdrive band several times (but few enough to count on one hand, maybe 2)?
                    Or should i be safe?
                    Still driving her in D; new servo pin is coming Thursday.

                    Comment

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