Truck wont start with out a jump. Changed starter and selinoid. Had battery checked and charged. Started right up then checked again a few hours later and cranked right up checked a few hours later and wont start. Please help

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Sounds like its the battery and you was running the car with alternator during your 12 hr run. Thus once stopped. The battery being done for doesn't have enough juice left. try a trickle charge overnight and try again. If no joy check the voltage output of the battery. And if low a new one is needed. Even when the new one has been fitted check the voltage again once running to make sure the alternator is still charging right. Hope this helps

check the resistance on the wires from the battery to your fuse panel and your ground wires also check to make sure you have good connections inside your fuse box if all is good there try to bench test the starter by applying a direct 12 volt power supply to.

Check the cables. Did the test the battery under load?

replace battery.may have a bad cell

sounds like you might have blown the fuse for the alternator or the wires for the alternator are dirty loose and not charging the battery right

get a load test done on you battery and alter nator and check your starter for corrision check battery connections before you jump start it and when hooking up cables to your truck let it charge for a few minutes before you crank it if alternator is fried it will only run on juice of battery then will die.the clicking sound is your starter trying to engage but not enough cranking amps left in battery if you can get it going or take the battery out and take to a good auto shop and get them to load test it no point replacing a good battery just to find out it is alternator or starter
I personaaly think it may be alternator but suggest you test if battery is good starter as well ! more thing check that battery terminals are clean and tight

Change the red starter cable! Good luck! Also you may have a fusible link that has burnt out . Check for link location with parts store.

Check the battery +12v power connection to the starter is in good order,
Check the ground connection between the battery negative and the engine/starter motor is robust and intact.
If no problem with above, replace the starter motor.

get under and hit starter with hammer a few times