1981 ford f150 it wont shift out of first gear unless u take your foot off of gas petal

SOURCE: Problem with 95 ford f150 v6automatic transmission -hard shifting

A sticking 1/2 shift accumulator or broken spring in the 1/2 shift accumulator.

SOURCE: 1995 ford f150 4 x 2 4R70W auto trans won't shift

check vacuum and electrical connections

SOURCE: 2001 ford F150 will not start unless pushing gas

you need a IAC Idle Air Control valve

SOURCE: ON MY FORD F150 IT WON1T GO INTO REVERSE. SHIFTS

Call a dealer about a new recall. There is another problem in the cruise control that is making it hard to put a vehicle into reverse. There are also problems with brake lights and dash indicators for the ABS all caused by the cruise control. This includes about 16 million various Ford products.

SOURCE: my 04 ford f150 wont shift into 3rd gear. when its

It can be the programming for the Electric shifting transmission or the 3rd gear Solenoid is acting up. On some models you will see 3 identical "Caps" on the side of the transmission. These are the ends of the Solenoids. If you can find the wire connectors to these devices you may be able to uncouple the connector and check the internal pins for corrosion. Clean off the corrosion and you might have a chance of restoring the action.

A really good transmission shop may be able to replace a Solenoid without pulling the trans. The main problem with removal of this part is the plunger end is holding the friction band in place for that gear. The band must be held in place while the part is switched and it takes a skilled Mechanic to do it. After the repair the band may require adjustment which is done by moving a adjustment stud on the opposite side of the trans from the Solenoids.