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Keep us posted...I'll respond over the weekend if you haven't solved the riddle by then...

Moses

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Update: I had the EGR delete plug in incorrect, swapped it around and the 624 & 629 code went awAy. But the shifting problem is still there. I replaced the solenoid pack and went through the valve bodies with my Trans builder and everything checked out. I cleared the codes and I am not receiving any codes but the Trans still is not shifting correctly. The Trans builder recommended replacing the psom or bypassing it. Is it possible to bypass it? I am at my wits end with this thing. Any help is much appreciated.

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I did some research.  Many find relief from a PSOM (speedo unit and module) changeout or even an engine tune-up.  If the ABS module and VSS systems check okay, the ECU/PCM comes up often as a trouble source.  Some find that simply unplugging connectors and reconnecting the harness plugs to the modules can help.  I know this is true from the Jeep systems, which have notoriously poor connections in many cases.  Black oxide coating on connector slots and pins is a clear sign of resistance problems.  Clean with spray electrical cleaner and fine Scotchbrite, never by scraping.  Do not scrape pins or slots with a small screwdriver blade or sharp edge...

 

I'm not an advocate of "parts replacing", and I always want a clear solution.  New modules are too expensive for "testing" purposes.  I found that Module Masters at Idaho can do a quality rebuild of an otherwise spendy module, and there are other module rebuilding companies that come up in searches.  Module Masters did a GM/Kelsey Hayes ABS module for my son's S/T10 truck for $130.  GM wanted $800 for the module.  The rebuild included upgrades around known weaknesses in these modules.

 

If the engine is in good tune, I'd at least try fiddling with the PSOM connector, which could point to a connection or speedo/module problem.  Don't rule out the ABS system, as that interfaces with the shift and PCM/ECU functions.  Since the truck ran okay then suddenly started this disturbing cycle of troubles, I'm not quick to tear the whole truck apart.  Concentrate on speed sensing devices and systems that feed vehicle speed information to the transmission shift processes.  I would test devices before arbitrarily replacing them.  Parts replacement cost is too great for experimenting.

 

Address one device, harness or function at a time to pinpoint the issue.  The symptoms you describe are seldom "multiple defect" troubles.  If you send off modules for rebuilding, ask that the shop test the device first to determine whether the module is actually the trouble source.

 

Moses

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So tonight I found out that my 1992 did not come with 4wabs. The VSS is wired straight to the PSOM. I attempted to wire the VSS directly to the computer but it would kill the engine once the tires were moving. So I put it back together as factory and now I am thinking I will try my buddies PSOM. Any other ideas?

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Does the truck have rear ABS only?  Check out wiring to the rear ABS system.  Does the ABS pick up a signal from the ring gear tone ring and a sensor probe?  Check plug connections for corrosion or poor contact.  Still thinking of the speed sensing system.

 

Moses

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Last night I swapped out the PSOM and MLPS from a good running vehicle and i got the same issue.  No codes shifting poorly, not going past third.  Then I gapped the VSS from .045" to .02" from the Tone ring and began getting a different reaction from the transmission.  It was shifting through 3rd and would jump into OD then back out then back in.    I believe the VSS is the culprit (even though it is brand new) so tonight i will swap it out to see if it is truly the issue.    Thanks for your help y'all.  

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Check the tone ring sensor pickup and its lead with an ohmmeter for opens or out-of-whack resistance.  This is why I asked about rear ABS and a pickup.  You could be right about the VSS or possibly the ABS module.  Try not to spend excess money on parts replacing.  Logic points to under-chassis stuff that gets exposed to vibration, the elements, corrosion and shock loads.  Connections, wire opens and excess resistance can raise havoc.  Often parts replacement can "cure" the issue by simply chafing corrosion off the connector contacts during installation.  The new part gets the credit.

 

Moses

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So this weekend I got some solid time to investigate.   I double checked all the connections, checked the gap on the tone ring, and went for a test drive. In drive, it goes through all of the gears and into overdrive, shifts down to 2nd when I manually pull it down, but it will not go into first gear when  i pull it into first at a stop.   Now time to look into that.   Thanks for  your help Moses!   

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Help!  A friend changed her trans fluid and filter on her 1995 F150 4x4 with E4OD that was acting fine,just regular maint.  She didn't know she had a torque converter drain plug, so just filter and fluid.  Truck started shifting hard into reverse and drive immediately after.  When she realized she had a drainable TC, all fluids were replaced. then truck had to be revved to 1200-1400 to engage.  Fluids removed and filter checked, all good and replaced.  Truck won't move now and TC isn't filling.  We also checked the cooling lines for blockage, all lines are clear, no fluid coming out of line to cooler when running, tranny has fluid.  The drainback valve has also been checked.  I find it hard to believe the pump went bad because of a filter change. MLPS was changed also just as a guess.  Truck is not filling the TC. Is there a valve that might of got stuck?  She's a single mom, and really hopes someone can help.   

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The pump inlet filter can clog during a filter and fluid change, though this is odd unless a heavy dose of fluid contaminants circulated through the system.  You share that the filter looks okay.  The only way to confirm a clogged filter screen is to remove it from the pump inlet and pour fluid through the filter matrix. 

 

There is an O-ring at the transmission case inlet for the filter tube.  This O-ring could be damaged or missing.  This would cause cavitation, an air gap, or reduced flow.  If the filter neck is not sealing properly, this could prevent fluid from picking up.  Check for the filter neck O-ring and its condition.  The O-ring could have fallen out or it may have become damaged during the filter change. 

 

Note: To save the cost of more new transmission fluid, I would filter the relatively new fluid through a piece of clean 100-mesh screen.  I get this mesh screen in stainless or brass from MSCDirect, a 2-foot square piece is plenty.  (McMaster-Carr or Grainger likely has it, too.)  I run the fluid through the screen and into a clean pan then reuse it.  I would change the filter if suspect, it's cheap enough.

 

You can get a rough idea of pump output by disconnecting the pressure side oil cooler line and aiming the tube end into an oil drain pan.  Run the engine at an idle very briefly to see whether fluid pumps out with force.  If not, the pump is not picking up.  Discharge here is not proof that the pump is putting out adequate fluid pressure, but it should indicate whether the flow is adequate enough to fill the torque converter.  You can test actual pressure with a gauge at the pressure test ports on the E4OD transmission case.

 

Since all was well before the initial oil and filter change, I doubt there is a sudden problem with the converter or pump.  There will be, though, with continued attempts to drive the vehicle without adequate fluid pickup volume.

 

Moses

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Hi, we triple checked the filter o-ring, gives a tight seal.  I rechecked all the lines for blockage again and all were clear.  There is no fluid coming out of the pressure tap on the side either.  An old Ford mechanic told me to try blowing air through both in/out cooler lines into the tranny, to see if some check valve may be stuck.  Didn't change anything, but could hear bubbles in pan.  So assume all those are clear. Is there any other valve that could be stuck?  Maybe one blocking the pump flow to the converter? I did blow air like he said from the cooler fitting at the radiator and get a short flow of fluid, maybe 3-4 seconds with engine idling.  Strange indeed.  Seems almost like it was clogged between the pump and converter before the fluid change, but the converter was full, so everything worked.  Make any sense?  You mentioned the pump inlet screen, is that different than the filter, and if so, is that accessible from in the pan, or does the tranny need disassembly?

 

Dave

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Well, your comment might make sense: "Seems almost like it was clogged between the pump and converter before the fluid change, but the converter was full, so everything worked."  If there is limited flow to the converter but the converter is full, it could function and stay "topped off".  Draining the unit would create an empty situation, but the converter would eventually fill up, even at the slow fluid pace.  When you move the selector into each gear position, can you feel a distinct "shift"?  If so, this would indicate that there is fluid apply pressure within the unit. 

 

I would stop the "second guessing" and do an actual pressure test.  Get a gauge (relatively inexpensive) that will handle the pressure requirements here.  Gauges come with fittings and adapters.  This is a straightforward test and offers a "flow chart" approach for diagnosing trouble:

 

E4OD Pressure Tests.pdf

 

Once you know whether there is control line pressure, and how much, you can pinpoint the source of trouble.  The only in-chassis "fix" outside of pump and valve body work is a solenoid or electronic  issue.  Pulling solenoids and cleaning passageways could help here.  Before any speculation about solenoids (or checking for codes with a sophisticated diagnostic tool, which the dealership would do), confirm the fluid line pressure.

 

Let me know what you discover...We can drill down further once you have a clear picture of the regulated hydraulic line pressure, which will be the reading at the test port.  The test is external to the unit and does not require pan removal, which you should be pleased to know.  Do not continue to run the equivalent of "stall tests" with the transmission not fully engaging, or real damage can occur to the converter or transmission internal hard parts.

 

Moses

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Posted · Report post

Thanks Moses,

I did the pressure test as directed, zero pressure. Fluid level is correct. Looks like the pump failed. Unless you have any other ideas. Gauge is serviceable by the way, I checked my F150, worked as advertised.

Dave

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Dave...This is a definitive test.  There's obviously no pressure being produced.  If you go down the flow chart, there are some in-chassis items that could cause the zero pressure, consistent with your earlier pursuits.  Several are valve body related or possibly a loose solenoid or clogged solenoid filter, which gets accessed with the valve body removed.  This solenoid or filter, or the main regulator valve, could be at fault.

 

If you'd like to make a last ditch effort to get this transmission working without a complete teardown and rebuild, you might try rebuilding the valve body.  Clean the solenoid filter hidden by the valve body while you're at it.  The main regulator requires access to the pump, and if you go that far, you're likely rebuilding the entire transmission.

 

Still puzzling over why this unit worked fine until the fluid change?  A valve like the main regulator might be your focus, though I'd do the valve body first.  "Wish thought" logic is that a valve became stuck with the dropping of the pan, fluid draining and a filter install.  Removing the filter allows drainback from the valve body.  Conceivably, valve body parts, a solenoid, the solenoid filter or the main regulator could have become stuck if drained of fluid with contaminants involved.  Despite the filtration, valve bodies and internals become quite full of fine debris over time.

 

That's as far as I would take it:  a carefully valve body rebuild and assurance that each valve and bore is functioning properly after thorough cleaning.  Removal and cleaning of the solenoid filter while the valve and control bodies are removed.  If that doesn't do it, I'm on the bench for a "major rebuild", which is not extraordinarily expensive if you do the job yourself.  Make sure you get a rebuilt converter, or the contaminants will start the process all over again...

 

Moses

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Thanks for the recommendations. We will pull the valve body as soon as possible, then go from there. Would swapping it from another E4OD from a 90 work? Either way, the valvebody will be looked at, then the solenoid pack. I know the 90 solenoid pack is not interchangeable, but will be checked also. If all checks good, and still no movement, rebuild time. Thanks for your help.

Dave

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You're very welcome...This sounds like the approach I would take, Dave...Keep us all posted!

 

Moses

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Hey guys! After googling around for answers, this seems to be the right topic to get to the bottom of the problem with the E4OD transmission on my 1990 F-250 7.3. Im a decent mechanic, but not that skilled in the technical terms of the english language, but hopefully we will understand each other somehow... ;)

 

The symptoms are similar to many of the other ones here. When put in DRIVE, the truck feels underpowered, engine revs up with very little motion on the truck. Takes forever to get the truck moving. I notice when I eventually get up to normal speed, that the speedometer keeps "flickering" while the transmission seems to go in and out of neutral and drive inconsistantly, but still with forward motion on the truck.

 

Seems to me that this might be an electrical problem, as the transmission fluid seems to be at proper level and clean when checked. Maybe a faulty contact point. The problem keeps coming and going, some days the truck handles like its no troubles at all, but lately it has occurred every time Im driving.

 

So where would I start troubleshooting with a multimeter? I've had my truck for about 4 years, but im not that familiar with the electrical components of the E4OD, so I dont know what to look for.

 

Another thing. Before this problem occured, the truck would sometimes start to roll after transmission was put in PARK position, with an awful metallic sound following. Like some cogwheels are grinding or slipping on each other. Dont know if its related though.

 

What do you think? :)

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Muddy Viking...Welcome to the forums...The PARK position ratcheting sounds like partial engagement of the transmission's parking pawl.  This could be a shift linkage (mechanical) issue.  The linkage may not be pushing the parking pawl linkage far enough.  If so, there's partial engagement at times.  This could also contribute to your partial or sluggish engagement issue with the transmission.  The manual valve in the valve body may not be aligning properly, causing partial gear engagement.

 

I would adjust and closely inspect the shift linkage from the column shifter all the way to the transmission case lever.  Be certain nothing is loose, restricting travel or out of adjustment.  If this does not turn up a specific and related problem to your poor transmission performance, let us know.  We'll delve further.

 

Meanwhile, do not drive the truck under load with the possibility of partial gear engagement or low pressure apply.  This will damage clutches and hard parts within the transmission.  Then you'll be facing a major rebuild.

 

Moses

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Posted · Report post

Thanks!

 

I'll try to take a closer look today. when the rain stops... ;)

 

Looking forward to put next years garageplans into action. "Field repairs" gets unpleasant after some time when rain, snow or mosquito are the only options for background enviroment... :rolleyes:

 

If it helps some the trucks mileage is about 155 000 miles, not sure about the transmission. Have not changed the transmission fluid during the 4 years in my ownership, but the truck doesn't get that much mileage during one year either.

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I've had similar issues as well. When i first bought the truck(93 lightning 351 w/e40d) it would shift hard but shortly after it just stays in first gear, the only way it shifts if you give it some gas. Speedo jumps sportadically at 55+mph(speedo worked fine, only replaced VSS for a troubleshooting step for the transmission). Here 's a list of what i've done.

Replaced:

VSS(twice)

TPS

New PCM Relay

Replaced all fuses

Neutral safety switch(twice)

PSOM.(went back to orginal after no change)

shift soleinod

+

Transmission fluid/filter change(no metal shavings found)

replaced springs accumaltor body

 

The wierd thing is that it would shift fine after a hard reset and then go right back to delayed shifting.I'm down to either a bad PCM or the clutches/bands are worn out in the tranny. Please help.

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351Lightning...Nice truck!  You have hit a lot of possibilities with your troubleshooting and parts replacement.  The clutches and bands cannot be ruled out, but this is usually symptomatic of slippage and clear signs of malfunctioning.  If the gears hold firmly, and if there is no slippage when the unit does shift between gears, I would not suspect the bands and clutches yet.  That's still on the trouble spot list, though.  Debris in the pan, especially a lot of friction material and metal, is symptomatic of clutch and band troubles.

 

Is there a possibility that a shift kit was installed in the valve body?  You purchased the truck pre-owned, and a Lightning could be a candidate for aftermarket tinkering.  The original symptoms sound like valve body related issues, like high pressure occurring and causing hard shifting.  I would check overall hydraulic pressures and apply pressures in each gear.  This may show high pressures at the wrong time, and that could be a valve body issue.  Holding in a lower gear is usually VSS, governor, solenoids or hydraulic boost pressure.  A defective or improperly staged valve body could cause these symptoms.  You've doubled up on the VSS already.

 

Hydraulic pressure tests are a time-honored troubleshooting measure for automatic transmissions.  The transmission needs the right pressures to shift properly, to hold clutches and bands, and to send signals to the governor.  Torque converter slip is a separate issue, but the transmission itself relies on proper line and valving pressures to perform its duties. 

 

There are hydraulic test sequences in the factory workshop manual.  If you do not have access, I can provide this information for your E4OD.  Before rebuilding the transmission, perform the hydraulic tests, some of which can be simulated with electronic troubleshooting steps.  Others require a pressure gauge and sequence tests.  Hydraulic pressure, fluid routing, solenoid switching and boost pressure timing are each critical to proper shifting.

 

Moses

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So here it is.

I own a 1995 Ford F350 7.3l turbo diesel dually 2WD with 300,000+ miles on it and E4OD trans. before taking it on its first long drive to Pennsylvania from North Carolina I checked all fluids and found the transmission fluid low and added DEX/MERC to the proper levels. as soon as I hit the highway it fail to shift past 3rd and jolted when it shifted from 1st to 2nd. reverse and neutral worked fine. I took it home and cleaned all the connectors on the transmission. I have not pulled codes it does not have obdII. I will pull them as soon as I can. when I tried to drive it the other day it had the same issue but now it takes higher rpms to make it move and slips in and out of gear at low speeds and idle regularly. it will stay in first for a few seconds then no gear on and off until it gets going. my overdrive button on my shifter doesn't work and my shifter is misaligned so when its in drive the shifter is actually on 2 its been this way for awhile with no issue. I also just had to replace the headlight switch and dimmer because it burned up. I could really use some insight and you guys seem extremely knowledgeable on this transmission. anything you could tell me would be very much appreciated.

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MurphyLaw...Looking at the addition of fresh ATF as the start of your transmission's problem, this sounds like the fresh fluid may have floated debris from the pan or moved sludge around.  Sludge can also loosen and clog the internal pump screen, a "worst case scenario" since the transmission must come out and apart to remedy.  Let's not race to that prospect just yet.  Granted, if the transmission is original and has never been rebuilt, there is a list of possibilities.

The shift linkage should be adjusted/aligned to assure that the valve body is directing fluid properly and with enough volume.  For openers, the rule of thumb is to drop the oil pan and check for debris in the pan.  Note the type of debris, a few cell phone photos would provide something we can evaluate.  Change the filter while you're in there.  Make sure the oil filter pickup screen seals properly to assure fluid pickup.  Replenish with fresh fluid, this is just the pan fill and does not include the converter.  To include the converter, an option would be a machine flush with flushing equipment plus the installation of a fresh filter.  Given the symptoms, I would drop the oil pan to see what's accumulated there and spare the cost of a full flush.

Start with these basics.  The change of fluid and a new filter may help.  Update on the results, we'll go from there.  Please clarify whether the mileage on this E4OD is 300K.  If so, behind a 7.3L Navistar diesel in an F350 dually, the unit's service life would be exceptional.

Moses 

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