Need help with a battery discharging problem.

My chevy truck has been sitting in the cold weather for over a month
now. It has a Die Hard Gold battery that is probably 2 years old. Well,
it would not start so I put a car battery charger on it for two hours. The battery
charger said 100% after 2 hours so I tried it and it started right up.
The temp was 25 degrees. I let it run about 30 minutes. When I got back
in the cab, the headlights were kind of dim and the gauge was at the
far left, about 8 volts? So I turned off the ignition and waited 30 seconds.
Now it won't turn over.

Not sure what to do now? Thanks for your help!


That sounds like a charging system problem to me. Now the battery may be
dead as well, but even a dead battery should not show a voltage DECREASE
with the engine running over a half hour period. It could also be a bad alternator
as well. Hopefully you have jump starter to carry with you. In case your truck dies again in a bad place.