You may want to just change the battery cables completely, if your end terminal was corroded there may even be corrosion down inside the cable that you can't see causing poor current flow. Check the alt. to battery cable too, maybe one end or the other is almost broken right inside the sheathing or torn away from it's connector pin/ring but you can't really see it. I have sometimes found electrical problems to be an almost severed wire or connection that looks fine at a glance.

Did you drain your battery by accident some time before this problem happened? Even months ago? Reason being once your battery is drained it usually needs to be charged with a charger for a long period, not short drives (an hour or two is a short drive) because the alternator doesn't provide enough current for long enough to charge the battery deeply again so effectively your cold cranking amps are very low and if the temp goes down or your truck just sits for a while that superficial charge will not be enough to start up again. The parts store quick charge probably helped juice it up, but if you can, put it on a low amp long charge over night. Disconnect your neg. cable if you do this. Worst case, your battery is not taking a deep charge any more. Parts store gave it a fast charge with a lot of current which is a bandaid but if the problem happens again consider a new battery. Now would be a good time to check the water level in your battery if you have one that requires/permits filling. There will be a max and min fill mark on the side of the battery like on a fluid reservoir. Use distilled water only to bring it back up to max. If you have a no maintenance battery, do not try and remove the cell caps.

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