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The brake band is released by applying 3rd clutch apply fluid to the reverse side of the brake band servo piston at the 2-3 upshift. The piston apply fluid is not removed so brake band release is dependent on correct 3rd clutch apply fluid pressure acting on the reverse side of the piston. The reverse side of the servo piston has a greater surface area than the apply side so there is a mechanical advantage, however, any leaks in the 3rd clutch apply fluid circuit reduces pressure causing the brake band to drag and wear away the friction material. Some of the "shift kits" enlarge selected 3rd clutch fluid orifices to increase 3rd clutch pressure. Did you enlarge or block any fluid orifices when installing your "shift kit"?
 

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Discussion Starter · #23 ·
I remember putting the drill bits to the associated holes and they where already that size or slightly bigger... So I thought someone had already done it. There is also a little aluminum plug you get and supposed to smack it and drill it. But I couldn't find the plug do never did it. I wonder if the hole in the plate are too big or if I should get a new one so I know it's right?
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Shift Kit hole 2b is valve body plate hole #20 which is 2nd clutch apply fluid from the 1-2&3-4 Shift (A) Valve. Shift Kit hole 2a is valve body plate hole #17d which is D 3 2/1-2 fluid to the 1-2&3-4 Shift (A) Valve These mods presumably firm up 2nd clutch apply by increasing pressure.
 

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Discussion Starter · #25 ·
Ahh ok. Thanks for everything... I'm going to take the tranny out again. 3rd time. I ordered the brake band. When I installed the shift kit I put all the springs in... I think it's probably safer to not have full pump pressure... Here is the instructions I used. I would like to undo anything that is really not needed. Ive been looking up separator plates and I can not find any. Where could I find one? Thanks again, I appreciate it
 

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Orifice #22 is for the servo release fluid, #19 is fo servo apply fluid.
It appears from the directions that you placed a plug at the #22 location in step 3.
Does this plug actually block the #22 orifice?
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Did you drill out and thread the 2nd clutch and 4th clutch apply pressure ports and the servo apply and release pressure ports when you rebuilt the transmission?
Any idea how big the hole is in the plug you installed?
 

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Discussion Starter · #31 ·
I didnt thread anything I know that. As far as drilling, I just drilled out the holes that step 5 had me drill. I don't know the hole size I can find out. I'll try calling superior or check when I get home... I know it is touch under 1/8" I really appreciate all your knowledge
 

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Discussion Starter · #36 ·
Where could I find the pressure numbers at? I read in that article servo release pressure is 10 psi or more below line pressure, there is a leak in the release circuit. I need to drill and tap 2nd and 4th to make sure I test everything right?
 

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Discussion Starter · #37 ·
ALSO, can I check the pressure of these ports when the transmission is out? Or do take it out drill and tap then install it and test it. I sure hope not, the article that to you sent me says do do it hot.
 

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Drilling and threading the additional diagnostic pressure ports is something you can do when you have the transmission disassembled for rebuild.
You can also drill and modify the main case to add an AFT dip stick, there is a discussion in the forum on this mod.
The transmission has to be in the truck with the engine running to have the hydraulic oil pump make line pressure.
 
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