Was at the grocery store and when I came out, fired the truck up and started to exit the lot. Rpms dropped to about 2-300, lights dimmed, truck died. When i turn the key, theres a click click click thats very vague, inside the cab only, so the starter was not getting any power. Buddy comes to jump me and the truck fires back up and runs fine. Get to my house, turn it off to see what happens, and it won't fire back up, same thing. Alternator, battery, or what else?