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Discussion Starter #1
I recently rebuilt my 47rh auto trans. Everything shifts and operates great except second gear slips really bad I readjusted the front band to spec and test drove and it still slips. If i cruise on flat road it does ok but if you get after the throttle or driving up a hill is starts to slip. I'd really appreciate it if somebody can give me some insight on what this problem could be.

Thank you
 

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It sounds like your front servo is not holding the front band on. Did you replace the front band? Also the seal on the front servo could have got torn when you replaced it. you can air check the front servo , but you will need to remove the valvebody. Ther should not be any air bubbles coming out from around that front servo. I think the front servo is the only one you CANT check with a gauge. If you air check the front servo make sure the front band is not stretched and the ends are touching , there should be at least a1/4 " gap. Use about 40 psi of air with a rubber tipped blow gun. If you dont know where to check it let me know. mike
 

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Discussion Starter #3
Thank you

Thanks for your reply I greatly appreciate it. That makes good sense. Where would I check that at with the air?
 

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When you take down the valvebody the one plastic piston and spring will fall out. I think there are 2 or 3 5/16 holes around the outer edge there it will be one of those. Use about 40 to 60 psi with a rubber tipped blow gun , and you will see the front band come on. There should be hardly any leaks ( oily air bubbles ) around the front servo piston. Do this before you take the piston out to inspect it. You may want to get a bunch of rags ready for you and your floor:hehe::hehe:.. Good Luck mike. let me know if you need any more help. I am NOT a trans expert but i know a little:thumbsup:
 

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Discussion Starter #5
Awesome we'll give it shot I bet that's the problem sounds good. As you can see I'm no trans expert either I really appreciate your help. Hopefully I don't get too soaked LOL
 

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Also if you go to the tech section, down at the bottem you should read ( Automatic Transmission Function ) may help a little. Diesel Blood did a nice wright up there. mike
 

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this pic might help snapped a bunch when i did mine, somebody can photoshop that and tell him exactly which hole to use:thumbsup:



 

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12 valve, did you put the orfice in that came with your dunriite VB for the case. just wondering i didnt see it in the pic. Oh i took me a hour to type this , so i cant help with photoshop:hehe::hehe:. Anyway its one of the ones by the plastic piston. Make sure you let us know how you made out. mikeuz
 

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12 valve, did you put the orfice in that came with your dunriite VB for the case. just wondering i didnt see it in the pic. Oh i took me a hour to type this , so i cant help with photoshop:hehe::hehe:. Anyway its one of the ones by the plastic piston. Make sure you let us know how you made out. mikeuz
orifice?? lol what exactly are you talking about?:confused013: my diesel shop rebuilt it with all the goodies the first time around and when i broke my input i decided to tackle it myself and these are some of the pics from it...im no expert tranny builder by anymeans, but is there something missing or something thats different, lol i didnt mess with that thing just pulled the v/b to get to the band hardware, etc.
 

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the park rod was disconected, it doesnt get removed entirely, but the linkage with the little notches..that should get removed...it was my first time and didnt realize it, but that rod that goes back into the trans stays there, the notch thingy gets removed:thumbsup:
 

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Have you jumped into it yet? mikeuz
 

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Discussion Starter #15
Yeah I got it tore down and found it was the bottom seal on the kick down servo piston:banghead:. I appreciate all your help:yourock:

Thanks again
jake
 

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transmission troubleshooting

Glad to hear you got it fixed.

Just so you know, you can troubleshoot quite a bit without even dropping the pan. Chrysler was smart enough to put in several pressure test ports for you - they are the 1/8" NPT plugs sticking out in a few places.

If you would have stuck a 300psi gauge in the "line pressure" port at the bulge in the case for the accumulator (the "plastic piston" shown in pictures above) while keeping your throttle position steady, you would have seen line pressure drop severely as soon as the transmission tried to apply the 2nd gear band - indicating internal leakage is the problem and not band adjustment.

Keep in mind that transmission line pressure varies with throttle position. That is why that cable running up to the injection pump is critical for the transmission to survive!
 

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its been awhile sinse i did mine......if it has the tfod shift kit in it dont ya leave that oring out?
 
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