Still having problems with the transmission, but I have some more information regarding it now, to hopefully narrow down what is going on. I'm ordering an Aeroforce Interceptor to check the codes, but in the mean time, this is everything that is going on.

Truck is a 1997 OBS F350, 2WD, XLT, E40D, with 93K miles. Mostly stock, hasn't towed anything since the previous owner, however he was towing a 5th wheel and a boat in tandem.

- Hard shift in every gear (especially 1-2, and 3-4)
- No OD light blinking
- Erratic 3-4 shift (it usually shifts at 35MPH, 1500RPM, but a lot of times it'll shift at 2500RPM, or even 1300RPM.
- When manually switching the gears from 1-2-D, there aren't any problems, with the exception of a pretty bad vibration when getting off the gas in 1st.

I've already replaced the VSS with a Motorcraft part, replaced the EBP tube and sensor, and the neutral safety switch (it wouldn't start in park, only neutral, but thats fixed now). Fluid and filter are less than a year old, and still full.

I'm gonna check the pressure to make sure I'm getting the correct amount, but this has me completely stumped. Is there another sensor I should look at, or am I looking at a busted solenoid/accumulator, or is there something else going on?

 

Without knowing what codes are stored it's impossible to say what's wrong.

 

Mark can it have a code without the OD flashing?

 

Yes it can.

 

Got it. Well, the Interceptor should be here sometime this week, so I'll check back when i get it plugged in.

 

No chip on it? Sometimes the canned tunes makes it shift hard.

 

No chip, all stock with the exception of a CAI. I did find that fuse 16 was blown, but that has nothing to do with it. I checked fuse 17, since it goes to the Electronic transmission, but it was good too. As was fuse 9 under the hood.

 

Check for codes and report back.
Also might want to check the connector on the passenger side of the tranny and make sure the connector is clean and not full of water/mud and make sure you use dielectric greese.

 

I checked the connections this morning, and they were good. I did find something though. Attached to the same wiring harness that the neutral safety switch is on, there is some sort of round connector that has been capped. It's not plugged into anything. It runs along the driver's side of the transmission towards the back. Any idea what this is for?

 

Trans case plug prolly, for the lights on the dash.

 

^^^^ Sounds like the connector for the 4x4 lights. What color are the wires going into the connector?

 

It's taped directly into the harness, but i looked up a wiring harness for the 4x4 lights and it has the same plug. I'm 2wd so it doesn't matter

Interceptor came in today, so I pulled the codes. The only code I'm showing is P0603, and I had pulled the battery recently when I swapped the Neutral Safety Switch and the EBP Sensor. So there was nothing regarding the transmission. The fact that it works when manually shifting it makes me think whatever is going on is electrical, not mechanical.

Any other ideas?

 

I have had trouble with hard shifts in the past when I had my boost gauge vacuum line come loose.

And then I had hard shifts and torque converter not locking up.

I did finally notice I had a P0607 code and I replaced the barometric pressure sensor under the dash and my transmission problems haven't been back for several months.

Kevin

 

Yeah I'm still not showing any codes. Whatever is going on has to be electrical though, because the transmission shifts just fine manually. Really wish a code would just pop though. That would make this a lot easier.

 

I solved the problem!

Earlier I said I replaced the Range Sensor, which was a mistake. I meant to say I *bought* one. Today, I got under the truck to actually replace it, and the range sensor was extremely loose (I could twist the bolts with my fingers). The shifter cable was also rubbing against part of the frame, because the sensor itself wasn't seated correctly. After replacing everything and tightened it all down, I noticed several problems were fixed:
- My shifter in the steering column is significantly more stiff
- Truck starts in park (finally)
- Shift points were much more firm
- Erratic shifting has disappeared
- Mystery squeal that I assumed to be a bad wheel bearing disappeared (it was the cable against the frame)