So recently picked up a 92 f-150 302 with the E40D trans. I've been having issues with it shifting too early. If I come off of a dead stop under full throttle it shifts automatically around 3500. And if I full accelerate around 50-60 it also will not downshift. Any ideas ? I added about half a quart of trans fluid yesterday fixed it on the drive home but started acting up again today.
I would do a complete drain and change the transmission filter. Only the PO knows when it was last done if ever. Look for debris in the pan and Dark "dirt" on the magnet if so equipped. This will be metal dust from the discs, alot of dark material equals high wear in the transmission. Larger debris on the magnet or in the bottom of the pan means more severe damage. The shifting issue can be caused by shifting solenoids or the PCM. Sent from my SM-G930P using Tapatalk