When I bought my truck in April 2012 the starter was replaced. (so they said)........
anyway, I just replaced the starter myself 2 weeks ago and it is acting up yet again, doing exactly what it did before spinning but not engaging till after a few try's. I also replaced the solenoid on the firewall when I changed the starter.

What could the problem be? Why would it keep doing the same thing?

 

Take the starter back where you got it and have them replace it. Sounds like a sticking starter drive.

 

Did you check the ring gear on the flywheel? could be damaged/worn out..

 

cheap autozone made in china starter. get one of these. http://www.rjminjectiontech.com/collections/starters

 

Ford starters are pretty good. I've replaced a couple in my day but the problem always ended up being something else when I did replace them. Now I know if your throwing parts at it make the starter the last thing..

 

I took it back they gave me a new autozone starter and it seems worse now someone said it could be the flywheel What do you all think

 

Yeah that's what I said... Take the inspection cover off and look at it you have to remove the transmission to replace the ring gear on the fly wheel.