Automatic Transmission Problems

Discussion in 'Drivetrain' started by 97JF, May 31, 2016.

  1. 97JF

    97JF Member

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    Hi guys , I've started having problems with my automatic transmission on my 2000 GT 4.6 V8.

    When accelerating it shifts into 2nd perfect but it doesn't seem to like shifting into 3rd under load, as soon as you come off the throttle it then changes into 3rd ok, but on the throttle it will just stay in 2nd gear.

    I've checked the fluid and the level seems ok , fluid looks a pink/red colour still and it doesn't smell of burning or anything.

    The car has done 114k miles but I thought the transmission should have lasted a lot longer than that ?

    Thanks for any help.
     
  2. lwarrior1016

    lwarrior1016 Moderator Staff SN95 Supporter

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    Are you having any issues with the speedometer, or any kind of issues with throttle response or idle? Sometimes an output speed sensor can cause issues like this or a bad tps can do it too. Reason I went to those is because when you increase throttle/load, the shift schedules change and if either sensor isnt working correctly it may never meet the requirements it sets to make that upshift. Next would be to drop the pan and take a look inside.
     
  3. JerZeyStangz

    JerZeyStangz Well-Known Member

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    My friend had this issue with his 96 GT Vert, he drove the car very aggressively and somehow he messed something up in valve body so it got rebuilt with a shift kit. Every time he drove the car it would hold 2nd gear to long then finally shift to third gear when he let off the throttle. This is just a educated guess but one of the shift solenoids could be damaged. Whatever you do please post results so we can see what happened.
     
  4. 97JF

    97JF Member

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    No problems with speedo or throttle

    The strange thing is it goes into 3rd gear after kicking down ok but it's just the initial first time you accelerate it doesn't under load

    Could it be the vacuum modulator ?
     
  5. lwarrior1016

    lwarrior1016 Moderator Staff SN95 Supporter

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    These dont have vacuum modulators anymore. It sounds like it might be a sticking accumulator or valve in the valve body. I know some of those accumulator springs like to break and itll cause delayed shifting.
     
  6. DFG_magic

    DFG_magic Well-Known Member

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    Any codes? I'd drain the pan, change the filter and gasket and refill with new Mercon V. If you want, drain the converter as well. There is a 2-3 shift solenoid that's easy to replace as well but you'd have a code for that.
     
  7. 97JF

    97JF Member

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    Quick update , it seems to be the overdrive that is causing the problem , I switched the overdrive off when I drove it this morning and it seems ok but as soon as it's turned on I think everytime the car tries to shift into overdrive its slipping out of gear .

    Any ideas ? Thanks
     
  8. lwarrior1016

    lwarrior1016 Moderator Staff SN95 Supporter

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    Broken snapring on the overdrive servo, maybe. How mechanically inclined are you?