Truck wont start. Only clicking noise

Truth ... A little corrosion + cold temp will take you out of the game. I use this kit from WallyWorld on all our vehicles and it keeps me trouble free with regards to corrosion. Might be worth a shot before replacing that connector.

EDIT: some odd comments about a 50ct kit online ... Don't buy it online ... It's available in store last I checked. Each kit has the two pads and little can of spray corrosion preventative.

 

This^ X2. IF you have a starter contact issue, then the starter may have just decided to work at that point regardless of the battery jump. If its the starter sometimes it will turn, sometimes it wont. If it was a "BUZZ" most likely battery. If it was more of a "Click" starter contacts. Just my opinion.

 

Yep. If the battery tested good with a proper load test (different than 'charged fully'), then something drained it while you were in school.

Lots of other ideas tossed out here are worthy of attention, but always start simple and cheap.

I've jumped lots of batteries that have given good service for a number of years after. Usually because I made a mistake with some type of load, or someone previously messed up wiring somewhere, creating dark current. Usually a stereo or alarm install.

It could be the battery is tooting it's last. Or not.

 

I do not.

 

OK...OP, what was the answer? Or are you still walking to school?

 

Bump...