Background........When I would run short distances and turn truck off, started slow.  Ended up leaving it running on short errands, seemed fine.  Went to start at home one morning, batteries dead.  Had them checked, both batteries shot.  We replaced both batteries.  A week later, went to start, left it run to warm up, died.  Put the chargers on it, fired up.  No guages were working, was running like crap.  Had it towed to shop.  Alternator was tested and replaced.  NOW, one week later, my battery light just came on........HELP!!!!