Ford F150 won't start after replacing starter?

Ford F150 won't start after replacing starter? - 1

Won't crank over? Or cranks over but won't start? You probably didn't hook the wires up correctly.

If you have connected the wires correctly and you are 100% sure the new starter is good, you can get a new starter that is bad, then you have another problem. Possibly the ignition switch is bad or the main fuse is blown.

There was once a TSB about the solenoid pigtail wire being faulty and whenever you get a new starter for Fords with the 4.2 V6, 4.6 V8, 5.4 V8, or 6.8 V10 engines, they come with a new pigtail wire that you have to cut the old one out and meld the new one in its place to fix it.

So you have a "Won't Crank issue", not a "won't start issue. HUGE HUGE difference! This is why it is so important to take a piece of masking tape and label each & every wire that goes to the starter:
Top post, bottom post, left post, small post, right post, large post, whatever it takes to jog your memory. You need a schematic. Google: Starter wiring F 150.
Start over. You will get it.