4r55e intermediate band sticking

[mrfister11]

95 ford ranger 4.0 4x4 4r55e.. truck came to me with a bad transmission.. told it had no reverse and third..(direct clutch) so i took it out rebuilt it.. direct clutch burned to hell, piston seal in direct clutch missing an inch of it, center support rubber seals broke, torque converter junk. so i replaced all the clutches in drums and all in spec for clearance, replaced all seals in all 3 drums, all 3 bands for good measure, new servos for OD and intermediate, replaced seals on reverse servo. replaced torque converter, replaced metal seals on forward drum, replaced seals on pump. inspected center support for cracks and all bushings checked good. both one way clutches work perfect. dissassembled valve body and cleaned, replaced EPC with new green one. the servo piston and pin bores for all 3 servos are in great shape.

before i put the valve body on i pressure checked the drums. actually before i put the center support and drums i bench tested them then tested them in trans. all worked perfect. tested all solenoids and are within ohm range.

ISSUE is when it shifts to third it bogs down real bad like the intermediate band is not releasing.. to confirm this i loosened the intermediate band in increments until i had almost no 2nd gear but now it will shift into third fine. all this is testing the vehicle with the rear tires off the ground so it doesnt have a load on it..

things ive done:
removed transmission 3 times and went through it 3 times
went through valve body again
put a KNOWN working valvebody on it - same issue
went through the known working valvebody- same issue
changed all the shift solenoids- same issue
checked the intermediate spring with the OD spring for the servos, stiffer one is on the intermediate servo
tested the computer to see if it turns off SS2 when shifting to third. it turns off

no codes

if i do this enough times it will get the direct clutch hot enough that it will skip third and go right into 4th and then lockup and i have a delayed reverse so i know it is burning the direct clutch up trying to apply it while the band is still applied.

I AM AT MY WITTS END WITH THIS THING looking for ANY input and ideas. i am leading towards maybe a cracked case?? maybe its cross leaking and keeping the intermediate band applied?

side note this thing shifts from 1st to 2nd perfect.. doesnt hang up. only hangs going into third when all the solenoids are shut off..

another note when i first installed this it shifted into 3rd perfect two times before it started hanging up.. at same time o/d light started flashing and i found a broken wire for the epc solenoid so it had full line pressure at first. fixed that and still hanging up

 

[BrooklynBay]

Welcome to this forum! Did you check the manual slide valve & servo bores for wear?

 

[mrfister11]

yes the the bores seem perfect. changed all the o rings on solenoids etc.. like i said i have 2 different valve bodies ive tried this with. one is a known working one. same issue so i have to think something with case as the band is applied from valvebody and no fluid through rotating parts? and ive changed the seperator plate gaskets and double/triple checked for alignment.. ive had them off atleast 6 times and the issue doesnt change

 

[mrfister11]

maybe if i can figure out which valve applies the intermediate servo release pressure? that would help. im not sure if its just holding pressure to apply or just not getting the release pressure

 

[PopRichie77]

Did you air test the servo for proper operation with the valve body off?
Use 40 psi air pressure as higher may cause it to function.
The spring should release it enough that it wouldn't hold.
Sounds like the apply pressure is not releasing or the servo is sticking.
Are you sure the wires in the pan are good?

 

[mrfister11]

Yes I even pulled vb just now to try and look for cross leaks. I apply pressure to feed and as soon as I let go it releases. Did it 20+ times. No hanging up. Maybe another solenoid staying on is keeping pressure or somethi by. The wires look fine. This trans has been apart before and maybe the harness replaced as its not hard a nd brittle with insulation missing

 

[mrfister11]

Also I checked all solenoids from the external connector to verify everything and its all good



starting to wonder if the issue im having is what burned it up to begin with and maybe its a pcm issue or case issue.. thinking about changing seperator plates with another one i have just to see what happens

 

[mrfister11]

i think i finally figured it out.. found some diagrams and tracing all the fluid circuits i pulled some valves out and worked them alot to make sure they werent sticking.. tested all the clutches and both servos while i had vb off and everything still good.. put it back together.. same issue a few times then it started to act different.. so i went and drove it and after about 3 miles before i got back to the shop, i could feel perfect engagement of 2, 3 and 4. all seems good now. im done for tonight. do some more test drives tomorrow and hope all is good still