You didn't say how old the battery is, but if it will accept that much amperage
it's most likely completely dead or has a shorted out cell.
Use a voltmeter, if you have one, to check the voltage. 11 volts or less, the
battery is dead.
Check the water level and fill if necessary, then put your charger on the battery.
The amp meter on the charger should gradually decrease as the battery accepts
the charge. If it doesn't decrease, it's time to buy a new battery.
If you can jump you battery again and get the truck started, put the voltmeter on
the battery. It should read about 14+ volts. That will tell you if your
alternator is working.