Hello All,
i have been struggling with poor shift quality in my 1996 7.3 2WD.
When I initially bought it, it shifted so bad I couldn’t drive it. So I rebuilt the accumulator body with sonnax parts.
The previous owner put a huge line modifier in and I got rid of it for a slightly larger than stock one.
Trans shifted a bit hard but nothing I couldn’t deal with. I drove like that for 1 year.
Today I decided to install a dieselsite accumulator body and at the same time I got rid of a tugger plate that went between the AB and the trans gasket.
Well stupid me took off the lower valve body that attaches to the main valve body because I wasn’t paying attention.
The check ***** fell out and I had to put them back where they came from. I followed directions I had from the factory Ford manual, 2 5/16 check ***** and 2 1/4 check *****. I then torqued the VB back on and took off the AB. I then removed the screen that’s under the AB and then removed the calibration plate from the trans.
I then installed the dieselsite AB and torqued it.
I go to drive the truck and it has all gears manually but it will not shift into 2nd automatically.
It also is shifting earlier than it did before into 3rd gear.
I lost a little fluid so I added more than I took out but so far I’ve added 2 quarts to the trans. I can’t really read the dipstick cause it’s always covered in fluid.
The trans electronically is trying to shift into 2nd. It revs out 1 and then bangs into 3rd.

 

If the trans had issues before rebuilding the accumulator body, there is probably more internally worn parts, specifically the Intermediate One Way Clutch.
I would guess you need to pull the valve body, and re-check the *****, making sure you are putting the correct ***** in the correct place for your year of the transmission.
Maybe the following images will help:

 

I figured out the issue, a 5/16 check ball didn’t find its way back in the lower valve body, shifts into 2nd now, but it still has the same shift quality as the old accumulator body.
I put in a new VSS after that and nothing else changed.
I am going to have to deal with it until this winter, then I’ll probably go and rebuild the trans.

 

did you reset pcm so it can learn its pressures and such. shift quality means all gears or does it mean from stops etc
Have you looked at any drivetrain mounts?
a 97 heavier duty f250 probably qualifies for the updated diameter cooler lines from the 4r100 or whatever that are larger.
https://testing-public.carmd.com/Tsb...3787/tsb97-15A

• Date Reported MARCH 17, 1997
• NHTSA Reference #52014
• TSB Reference #97629

Description: TRANSMISSION- E4OD- HARSH/DELAYED 2-3 UPSHIFTS- VEHICLES WITH 7.3L DIESEL AND 49-STATE CALIBRATION- F-SERIES BUILT THROUGH 2/3/97 AND ALL 1996 E-350. *JD

also, just know, when trying to find out what is causing shift issues, excessive play or wear on every component inline of power transfer and also mountings are important to consider too. If you have loosey goosey mounts and a rear axle with play and your u joints all sound like my knees on a cold day (Im even young ;( )then you will have increased time to shift and that may be then harsh shifts because the transmission is trying to get the shift quicker but increases line pressure to do so, being harsh. And of course, bad mounts mean more twist and stuff, but so does vibration and harshness transfer. The e4od isnt exactly smooth as can be but it definitely isnt supposed to be harsh. are all your engine sensors properly adjusted, in spec, any engine driveability issues on its own. An engine with poor power balance and one that doesnt handle sudden load very well would also do that. Basically imagine shifting your vehicle from park at 400 rpm on a gas v6 thats barely chugging at all, having to shift is a big demand and a computer may compensate for that by trying to increase speed and add fuel etc etc which will cause it to probably hesitate before banging up to speed and thus clunking into gear.

i only say look at the TSB because I looked at a lot of tsbs from ford for the era and I have a f150 but I say a LOT of titles related to e4od shifts, rear brakes, a lot of calibration TSBs, and various production cut offs that may affect things. So you may not have a issue with your truck that ford has not already found a fix for

 

I have not disconnected the batteries yet.
I am willing to bet the leaf spring bushings are SHOT, the previous owner didn’t do much other than change the oil and air filter.
All the bushings in the front end had to be replaced so I would assume the rear needs it as well. The trans mount looks good, and the u joints are relatively tight, the rear most joint will eventually need to be replaced as it’s starting to have play in it.

The other weird thing the transmission does is shift into OD at 35 MPH when cold, if you then speed up to 40mph and then go back down to 35mph to induce a downshift, it will not shift into OD until 43mph after that.

That makes me think some of the issue with this is computer related but I’ve tried many tuning solutions and none seem to work with the truck.

I should probably mount a go pro under the truck to see what (if anything) is moving during the shifts.
I did it before and noticed a lot of axle wrap so I bought traction bars. That helped a lot but the trans still shifts hard on 1-2 and sometimes shifts hard on other gears.

I don’t really drive the truck enough to care about the shift quality, it’s purpose is a drag racing truck, it surprisingly shifts fine at the strip, I’m assuming due to the suspension being loaded.

Life goes on, and so does my search for my solution

 

makes me think the computer doesn’t see a load decrease like it wants. I don’t know how the diesel computer works, but what if you cycle the switch when it won’t kick back down. You sure you didn’t just feel the torque converter lockup?

 

That isn't necessary. The PCM for an E4OD wasn't capable of learning anything. Ford didn't have that feature until 1999, and the diesels didn't get it until the 5R110W in 2003.

 

this may seem strange. But take your truck to a flat straight road. Go in reverse and do about 5 hard stops from at least5, maybe 10mph. You have rear discs but there is a small chance doing so will unbind and settle driveline. Then. Once you did that. Drive forward without punching it and see if you have improvements

 

In reference to the OD shift at 35mph?
I know it’s going into OD, my edge CTS 2 and forscan both say 4th gear is commanded at 35mph when I feel the issue.

 

almost maybe sounds like a throttle sensor issue. You don’t have a throttle cable but I know the diesels had a lot of trouble with the pedal assembly for a while