I am new to this forum and need some direction.
I have a 1995 F250 xlt 4x4 5.8 automatic
Trans e4od.
the truck only has 136k miles runs great drives great shifts great until you get on the highway. Let me explain, the truck is going say 71 72 mph- rpm 22 24 hundred come to a small hill very softly apply pressure to the gas pedal, the transmission will up shift rpm will drop to about 18 hundred continue pressure on throttle once you are at the top of the hill the transmission will downshift
and the rpm returns to 22 24 hundred.
Highway mpg is about 10, city driving ranges between 12 and 14. I need help with this.

 

Sounds like the converter clutch is disengaging to allow sufficient power to take the slight load Most E4ODs do this .
To prove this is all that is happening, which is normal, just press the overdrive button to OFF to keep the trans from going into overdrive.This will take it out of overdrive and keep it in third gear.Then if you press the overdrive button again , it should upshift and RPMs should drop.