FIPL, E4OD TRANS, SHIFT, FRIKK!!!!

[CaptTom]

Hey Burners!!

SO! My trans is having trouble turning HP into guts at the rears.

I'm having to throttle shift the transmission to up the gears, and it will drop down a gear at the first sign of needing to work a bit.

This dilemma fades in and out. Some days it all works great, then there's a slight hint of extra delayed up shifting, then a day or drive or two later, it will throttle to 2800 RPM and won't upshift unless I pump shift with the throttle. Doesn't take much of a throttle drop to get it to shift.

On freeway at speeds no problems, unless hitting the Grapevine, then it might downshift at 55mph while in OD. No trans light comes on at the OD switch.

As soon as I let off the throttle, the trans readily wants to downshift, even going downhill.

Happens hot or cold.

Replaced FIPL, tuned it to 1.1V-4.5V.... smooth range of V up and down, no drops on meter in between on a hot engine aka properly warmed up.

So the question is..... ***!!???

Bad FIPL in spite of it holding good voltage with the hood up? I changed FIPL because of the description, however, same condition exists with new FIPL.

Thanks in advance as always.

 

[vegas39]

Fipl should be fine then, however I'd set the base voltage to more of around 1.20

Other than that, I'm clueless with the e40d

 

[CaptTom]

When I bump to 1.2V, the top goes to 4.7V.... Having troubles getting 1.2-4.5V

 

[FORDF250HDXLT]

That sounds more like sticking valves in the valve body than it does the TPS settings.The electrical setting of the TPS won't change how the trans shifts,from day to day.
Downshifting when letting off the accelerator,even when going downhill.......I don't have a clue what's going on there.Your issues don't sound electrical to me.They sound like valve body related issues.

1.2 V idle/ 4.7 V WOT is good though,by the way.These are about where mine are on my trucks.Nice shifts.

 

[CaptTom]

Would a trans flush help clean it up?

 

[Daryl4]

I don't have any solid answers but two areas to consider....

My new to me E4OD in my new rig was doing some odd somewhat random stuff. I flushed it quite a bit and it's certainly helped. To swap out fluid I do something kinda odd others think is silly, I think it works great. I "T"d into the line to the cooler with a length of hose and a valve. So to swap fluid I get it all warmed up so the level is accurate. Then use that hose/valve to let it pump out a quart into a bottle, then add a new quart, repeat. It'll use more fluid overall if swapping fluid is the only goal but for me it was as much about swapping fluid as it was getting crud out of the internal passages without having the rig down. So I swapped a few quarts a day for a while and it got quite a bit better. That and I'm hanging onto the old fluid, I'll get around to filtering it and using is as fuel.

Second, there's a vehicle speed sensor(VSS) that only talks to the transmission controller. So if it's not working right the tranny will do odd things but the speedometer will still work. If that sensor isn't working right the controller won't know your at speed and that it should upshift. That sensor is also under the rig with not all that great connectors/wiring could be as simple as crud in the plug.

 

[Sidewinded_idi]

Is your speedometer/ odometer and tach working?

 

[snicklas]

Second, there's a vehicle speed sensor(VSS) that only talks to the transmission controller. So if it's not working right the tranny will do odd things but the speedometer will still work. If that sensor isn't working right the controller won't know your at speed and that it should upshift. That sensor is also under the rig with not all that great connectors/wiring could be as simple as crud in the plug.

The speedometer continuing to work is only on the Bricknose (87-91) trucks. In the bricks, the speedometer is still cable driven, and the VSS plugs into the transmission/transfer case first in the cable hole, then the speedometer cable plugs into the VSS to run the speedometer. On the OBS (92-97) through the current models, the VSS is in the top of the rear differential and reads a tone ring on the carrier. This VSS controls both the speedometer, transmission and rear ABS. If it truck isn’t getting that signal, the E4OD, speedometer/odometer and RABS will not work, the Rear ABS light will be on and the O/D Off light will flash and the transmission will be in limp mode.

 

[saburai]

Good information, thanks Scott!

 

[CaptTom]

Good gouge!!

I forgot to mention, the tach will drop to zero every once in awhile when I take my foot off the throttle..... which freaked me out the first time it happened. Truck still running normal even when tach drops off the grid. It only happens driving in town as I pump for fuel in traffic, never at constant speed. I thought it might be the tach sensor at the IP gear housing, I've replaced it twice in five years, but the tach typically bounces erratically and thought nothing of it. The zero drop has only occurred a few times over last month or so.

Speedo appears to work great.

No OD lights flashing on or off. Tested OD switch and it appears to function.

 

[Daryl4]

The speedometer continuing to work is only on the Bricknose (87-91) trucks. In the bricks, the speedometer is still cable driven, and the VSS plugs into the transmission/transfer case first in the cable hole, then the speedometer cable plugs into the VSS to run the speedometer. On the OBS (92-97) through the current models, the VSS is in the top of the rear differential and reads a tone ring on the carrier. This VSS controls both the speedometer, transmission and rear ABS. If it truck isn’t getting that signal, the E4OD, speedometer/odometer and RABS will not work, the Rear ABS light will be on and the O/D Off light will flash and the transmission will be in limp mode.

No ****, his truck's a 90

 

[snicklas]

No ****, his truck's a 90

He may not have known this. Apparently there are others that didn’t either.

The attitudes are getting a bit much here lately.

 

[saburai]

There's no such thing as too much good information!

 

[Daryl4]

There's no such thing as too much good information!

I and other professionals disagree. There's absolutely a thing we may call information overload. Whether done on purpose or not when pertinent information is included with other unimportant data it's less likely to be understood, absorbed, and utilized. In the long run you're correct but in the short term it's more harmful then helpful.

 

[CaptTom]

I'm looking for good gouge, not back biting. All info has to be gleaned, and that post had info for others as well who may be reading.

Yes, my truck is listed in the footer, but I always like the extra info because I get to learn a little more than what my original needs are.... I'm good with that.

Appreciate all comments as their intent is good.... and sometimes a bit playful which makes it more fun.

If someone has some more ideas related to my issue at hand, I'd still appreciate them. I know blog post diagnosis is just a shot in the dark, but, it points people in better directions on how to proceed than doing circles and tool tossing on a day off.

And BTW.... most all of my repairs and kewl upgrades for this particular truck all came from generous people on this board.

Thanks again!