New battery installed a few weeks ago - 120k on 2001 Silverado. When it is rainy out, the gauge acts erratically (yesterday the needle was between 14 and 19, today it is between 9 and 14 and the battery light is on. What can I check to figure out what might be happening?
Thanks!
Take it back to whoever installed the battery and ask them to check that battery cables. It sounds like one many not be making a good connection and may need to be cleaned. It should have been done when the battery was replaced, but it does not always get done or it may have been done, but just not quite right.
These are signs that the alternator has a problem or there is a faulty connection to it. You might want to have a shop do a load test on the charging system to check things out. You may need to replace the alternator.