Hindsight Is 20/20
When we installed the new battery we checked the charging system again (the lazy way mentioned previously), and since we saw 13.8 volts we released the vehicle. A few days later she came back complaining of the same problem. This time when we checked the charging system (same old lazy way) we noticed that the generator was not charging, so we recommended replacing the generator, because this type of generator uses a one-way clutch on the pulley and is known to go bad, so we figured (assumed) that that was why we had seen the system charge at some times and not others.
