I had a new battery installed at Auto Zone. Their best battery. The truck, 2004 F150 2wd, then had a short or drain on the battery. I have to take the negative post off the battery at night or it will drain the battery. I replaced the battery because the engine would quit running, intermittently. The new battery seamed to fix the problem, but now there is a heavy drain on the battery. With a meter in line i removed the cable to the alternator, no change. Removed the cable going back to the cab, no short ? hooked up the cable to the alternator, short came back without the cable to the cab. There must be some connection between the two. But where do you start? Help and thanks . Wildindian