ide check the starter before anything..most the time when you battery is dying doesnt it make like a slow sounds like theres not enough power to turn over(i cant realy describe it)but when a starter is on its last legs its make a somewhat fast clicking sound everytime you turn the key foward..but as said before if you get stuck somewhere you could crawl under the truck and give it a couple taps with a screwdriver(or hammer lol)and it should roll over but i wouldnt rely on that