The Butter - I have been lurking and seaching this forum for a couple of weeks now and the amount on knowledge here is mind blowing, the tech threads hold a wealth of information for the DIY guy. But even with all this information, I need some guidance on where to go next. So to try and give as much information as possible I am gonna give the whole story.

My son wanted a pickup very badly and traded his car for a 1993 7.3 non-turbo f250. pretty nice truck, and in his excitement he did not notice( or didnt seem to care he is only 17) the the truck had a significant shudder when under power. He was driving it and did not say anything about it to me, and one day I needed to go somewhere and drove the ford. Experiencing the shudder for myself, I asked him about it and he said, " I didnt really notice" lol. Well it was kinda like riding the rumble strip, so I am not sure how he didnt notice, but I suspected the converter and for a learning experience we pulled the trans to put a converter in it. While the trans was out i figured we might as well tear it down and go through it as the truck has 160,000. I was able to find a YouTube video on the process that was very detailed and did the rebuild. While I was in there the video showed a few updates, so I completed those and we put the trans and new converter back in the truck. Well the shudder is gone, but now it shifted very erratic, seemed like it shifted straight into third, so i went into diagnostic mode.

First thing i did was check for codes, and I got one for trans temp, and coastal clutch solenoid. knowing that i did not replace the solenoid pack, In hind sight i should have when i was there, and knowing the connector locks were broken upon removal, i replaced the solenoid pack and the connector. So I test drive, it is better, but now it is hanging in first unless I let off the throttle, seems to hit second, shifts into third quickly, LU next, then 4th. Doesnt want to down shift. No second gear if I manually shift. Seems like it is in neutral.

Check for codes again. nothing. all i get is system ok, 11.

I do some research here, find talk of MLPS, knowing that connector was also broken and the MLPS/neutral safety switch looked in ruff shape, I changed the MLPS and connector. Checked the FIPL, found dead spots in the range, replaced the FIPL/TPS and calibrated. Checked the VSS, and found visible damage to the VSS, So i replaced the VSS. On that note I did remember that the speedo bounced and the bounce was more pronounced the faster you traveled.

Test drive, still another change, and for the better, now if am easy on the throttle, no more than say 1/4, it shifts into second gear, and all others. once up to about 40 it seems to operate properly, down shift, Lockup when supposed to, downshifts on it own. But if i try to accelerate hard, it still hangs in first, seems like second is non-existant, if it downshifts from third to second its like it shifts into neutral. Also the speedo bounce is still there, even with the new VSS.

So I checked for codes, still 11. I am starting to suspect I screwed up in the trans, sure hope Whatever i did I can fix while it is still in the truck, i am thinking either the valve body, one of the updates was to change the * UPDATE* change to a one piece servo, and i did that update, maybe I installed it wrong dont see how tho? I have seen talk of the PSOM, i did remove the guages and reseated the connectors, but buying a new guage package is throwing money away without knowing for sure that is the issue, the only reason i suspect it is the speedo bounce with the new VSS.

So whats my next step? A match?

 

So moving forward, I removed the diff cover and inspected the exciter ring, there are chips in the teeth all the way around the ring. so something happend in there. I guess I need to drop out the spool and get the exciter ring replaced. I guess I would just leave it along and deal with the fluctuation if I was sure that it would not make the trans do goofy stuff, on another note the red ABS light is also on, and that signal runs through the RABS control to my understanding so I am gonna try disconnecting the RABS and see where that gets me. Before i pull the tranny and start to take it back apart looking for a issue, I would really like to be confident that the issue is mechanical and not electrical.

Starting to wonder if I didnt install the intermediate clutch one-way bearing in backwards, I was sure i double checked that it locked clock ways, but maybe i screwed that up.

 

interesting result, I disconnected the RABS control and the speedo bounce was all but eliminated, before at 60mph it was just between 60 and 65, now it is maybe bouncing 1 mph between 60 and 61. again still operates the same, if i am easy on the gas let off the gas at about 2500 rpm in first gear, its shifts into second, and as long as i dont punch the gas it will hold second and shift to third, if i push the pedal too hard it just blows right through like it is in neutral until it decides to downshift into first.

I am not an expert of the inner workings of the auto trans, as a matter of fact I barley understand how it works, just replaced all the parts inside like Instructed. So from the sounds of things the intermediate clutch is where this function happens, the shift from first to second, and since i am slipping the second gear, either I am not building enough pressure due to a bad lip seal, maybe i torn it on install, snap ring failure, something is causing it to slip in second. I think i have all but eliminated electrical possibilities, it must be mechanical.

Praying one of the trans Gods will chime in and tell me if i am on the right track, or headed the wrong direction.

 

I don't know just what your problem is, but you're on the right track that it is probably in the intermediate clutch.

 

And on that note, trans removal in progress. Thank you for the reply.

 

tore down to the intermediate clutch, at this point the only thing i see is the band is in bad shape, I did not replace it the first time, in hind sight I probably should have. But the question is, is the band the cause, or did i cook the band running it in testing? I still need to take apart the intermediate clutch and double check the lip seals, but the one way bearing is correct.

 

clutch discs in the intermediate clutch are junk, now those i did replace, so the question is would a bad band take out the clutch disks in the intermediate clutch. Or is there another problem that cooked them both?

 

The band did not cause the failure, it probably was damaged do to driving it with failed clutches.

What caused the failure? most likely a leak in the intermediate clutch circuit. Leaks could be with the case to drum or leaks between the valve body and case or in the valve body itself.

I have seen the accumulator valve body wear and the case warp in many of these. If you over tighten the three case bolts this can warp the case and cause cross leaks. They need to be tightened to 70 inch pounds and check the case for flatness after the bolts are tight with a flat edge. You should no more than .004 of a gap in this area.

 

thanks james, I did torque those bolts to inch pounds, i dont remember what the spec was, but the guy in the video was very clear about not over tighening those, I did not check for warpage, but I will this time.

 

Check your valve body bottom gasket, look for the case impressions on the gasket, if there is no impressions in the center area this is a indication of a poor seal.

 

Ok, so i took apart the intermediate clutch and the lip seals for the piston look fine, unless i have them orientated wrong, i dont see anything there. I checked the valve body gasket like suggested, and i see a very definitive mark in the gasket. I checked the surface and it is not warped, of course i will check again after i reassemble and torque the three bolts.

My concern is I still havnt found a cause for the clutch disks to fail, I understand it was pressure related, but it scares the crap out of me to reassemble without knowing i found what i did wrong the first time. Is there another piston that creates the pressure for second gear?

 

The pump creates all pressures. The valve body directs the pressure. To get pressure to the intermediate clutch shift solenoid B is turned on by the PCM. Pressure now flows through the solenoid to the shift valve. The shift valve moves to the other end of the bore, which directs flow to the clutch.

There is a check ball in the clutch that must seat to build pressure. As you know the lips seals have to be right, too.

 

so I did a little research and double checked the lip seals and they are installed correctly, I did find a issue, what it means or if this could have caused the problem? but what i found is, in the valve body, there is one check ball that is on top of a spring, it is supposed to be steel and smaller than the others, I installed one of the rubber check ***** there, the rubber ***** are bigger and therefore this circuit may not have been functioning properly.

 

and on the way back together i also found that one of the sealing rings on the pump shaft where it slides into the coastal clutch, was damaged, it was the one closer to the pump.

 

the check ball i screwed up was the EPC blowoff, so not sure what plugging this orifice would do, i have read where it being not restricted would be bad and probably explode the forward clutch.