First , I have a 2013 f150 and when I go to start sometimes it gives a light click click click ( very faint not long and not all the time) then truck starts. I replaced the battery a month ago - checked with meters at Oreilly's that starter and alternater were drawing good. ( Thats when I found out Battery needed replaced) now I have same issue a month later with new battery. All checks were good again yesterday. Is this a sign the starter is failing or can this be an ignition issue or some sensor? Thanks Mark

 

Possibly could starter solenoid going bad.. time for new starter

 

Clean all of the electrical connections on the way from the battery to the starter motor, both positive and negative.