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Discussion Starter #1
ok iv been searching and trying things and searching and fixing things still cant figour this out

99 f150
98 4r70 swap (truck had a c4 in it)
wiring came from a expedition and repined only a few wires for it to be like the stock harness
replaced shift solenoids
the tranny was "built" by somebody i traded the tranny for my c4 swap
has a PA auto auto transbreak vavle body

everything seems good
computer says o/d and D when its in drive with od switched on or off
its commanding the 3rd gear shift but nothing happens it just stays in 2nd gear

the wiring is correct for the solenoids i can jump them by powering them up at the plug on the firewall so i know the wiring is correct

i just cant see the tranny being broken if it stays in 2nd and does not shift at all it never neutrals out just stays in 2nd gear

i have loaded a stock tranny tune in the truck for now just to see if its gonna work,
my speedo seems to be maybe 10 mph slower than its actually going i know this will just make the shift point off a little.

anybody have any ideas ?? im pretty stumped at this point

NEW INFO
does not have a broken stub shaft tore the tranny down and its not broken,
direct drum clutches are a little worn down but should have worked, and the od band is a little worn down

so back to square one and i have no idea whats going on now
 

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its commanding the 3rd gear shift but nothing happens it just stays in 2nd gear
....i just cant see the tranny being broken if it stays in 2nd and does not shift at all it never neutrals out just stays in 2nd gear

The trans selects and holds 2nd if the pin wiring isn't correct. Depending on the year of the trans, there's two different pinout wiring specs. Are you absolutely sure it's wired up right?
 

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Discussion Starter #3
its a 99 truck with a 98 tranny from a mustang, i checked and checked the wiring, i can actually accuate the solenoids from the plug on the firewall,
it shifts 1-2 just fine and just stays in 2nd gear after that, and it will downshift into 1st like its suposto
 

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My idea is: - If indeed Electrical is good & Tranny is good then I say Main Valve Body is bad - Happened to me when I had a bad 2000 Main VB w/bad Main Valve.
 

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1997 Thunderbird 4.6, 1998 Mark VIII LSC
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Do manual 1 and 2 work?
 

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Discussion Starter #6
yeah manual 1-2 work fine, im building the tranny back up since couple clutches are kind of burned up gonna stack 8 in the direct drum and 7 in the foreward drum, need to make sure its not gonna happen again, this time im gonna take the valve body apart to see if anything is stuck
 

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Ran across a Thread that found loss of 3rd & OD due to incorrect assembly of 2-3 Accumulator Piston Asembly:

http://forums.tccoa.com/showthread.php?t=123268

"" As with the issue I mentioned before the direct accumulator piston would drop out of the bore and exhaust the direct pressure. The result would be a loss or weak 3rd gear and virtually nonexistant 4th. For some reason when the piston has come out of the bore for me in the past I have had issues from complete loss of 3rd and 4h, loss of 4th only with 3rd weak and in one case it felt like lockup did not work but worked great elsewhere. That one was the puzzler we thought it was a converter issue. That is the point at which I went to using the plastic taller pistons.

The 02 transmission has 2 stiffener plates on the transmission, the earlier model unit in your car had 3. In turn the "bottlecap" on the 02 is taller if you do not use it the direct piston will out stroke the bore making it slip in 3rd and 4th.
Alan
__________________
DirtyDog Performance.Com""
 

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Discussion Starter #8
yeah maybe i will have to try the taller piston when i put it back together, still would like to find something actually broken before i stick it back in for the 3rd time
 

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yeah maybe i will have to try the taller piston when i put it back together, still would like to find something actually broken before i stick it back in for the 3rd time
I don't know what a "PA auto auto transbreak vavle body" looks like - But there's a theory that IF it lacks the 3rd small "Pac Man" Plate like a 2000+ Main VB does it affects the stack height of how some of the 2-3 Accumulator Piston & Retainer heights work out in a no 2-3 Spring setup (preferred by virtually all the Gurus).

Sonnax says you can get VB cross leaks without the 3rd Pac man plate too.
 

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VERY COOL ~! ... the 3 Round "reinforcing plates" on the other side (top) of Main VB are called Pac Man Plates as they are round with little chunks out of them... as I said 2000+ Main VB have only 2 Plates - The smallest 3rd Plate is Under 2-3 Piston Retainer Pre-2000.
 

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Discussion Starter #12
ohh ok got ya, yeah this is a 98 tranny so im just gonna go through it all and check over the vavle body really closely, dont know what else to do
 

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ohh ok got ya, yeah this is a 98 tranny so im just gonna go through it all and check over the vavle body really closely, dont know what else to do
& Certainly it's occurred to you if it does'nt work after next install I'd try a stockish Main VB before I pulled entire Tranny again - Quite obviously that's a very nice Main VB you have but kinda unique so...
 

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Discussion Starter #14
yeah im gonna check it all out after i rebuild it, gonan cryotreat everything, and put it all back together hopefully in a few weeks ill have it back together
 

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Discussion Starter #15
ok so back to this again,

update,
pulled tranny apart, no broken stub shaft, infact it was still a stock one,
direct clutches were little burned up so rebuilt that one and stacked 7 in it
also stacked 6 in the foreward drum
replaced 2-3 accumulator and spring just for the hell of it
installed the retainer with pins facing down
pulled apart vavle body everything worked no broken springs nothing looks out of place
cleaned it all
checked wiring again for the 500th time all seems to be correct

still will not shift into 3rd gear, it just shifts 1-2 and stays in 2nd gear

im pretty much at my wits end with this **** im so sick and tired of pulling stuff apart somebody please help me
 

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ok so back to this again,

update,
pulled tranny apart, no broken stub shaft, infact it was still a stock one,
direct clutches were little burned up so rebuilt that one and stacked 7 in it
also stacked 6 in the foreward drum
replaced 2-3 accumulator and spring just for the hell of it
installed the retainer with pins facing down
pulled apart vavle body everything worked no broken springs nothing looks out of place
cleaned it all
checked wiring again for the 500th time all seems to be correct

still will not shift into 3rd gear, it just shifts 1-2 and stays in 2nd gear

im pretty much at my wits end with this **** im so sick and tired of pulling stuff apart somebody please help me
Have u already tried new shift solenoids? What about monitoring their signals to see if the are correct?
 

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PCM Reflash

You might try taking it to a shop or dealership to see if they can flash the PCM (powertrain control module, some call it transmission control module), or resetting it by disconnecting your battery for about 10 min ( think thats how you reset it ) A major tranny swap like that, your pcm wont know whats going on and it has to relearn "shift points" Hope this helps.
 

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did you read the first post ?
Yes, but just because the ECM is commanding 3rd gear doesn't mean the signal is actually getting to the solenoids.

If I had this problem, I would hook a voltmeter to the Shift Solenoid 2 wire right where it goes into the tranny at the harness so I could see if the voltage is actually getting to the solenoid.

On a 1999 harness, that would be Pin #8.



Good luck and let us know...
 

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Discussion Starter #20
yeah i have wired it like that and have checked that also its getting the signal to the shift solenoids,

i need to send the valve body back to pa i guess and have them look at it
 
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