Hey everyone Im having trouble with my truck for a while now. It started when my battery light went on and i got the alternator tested Advance and Auto Zone both said the alternator was bad. I ended up getting a replacement at Pepboys since they were the only ones that it in stock. After I replaced the alternator, the battery light was still on. I had Napa batteries in it from the previous owner and went through them to get 2 replacement ones. After I installed them the light was still on.
But the truck drove fine for about 2 weeks. Now the truck will only start when its jumped and after driving on the highway for a half hour the voltage on the batteries is 10.4v. I went back and had the new alternator tested and it passed.... Does anyone have any idea of what the underlying problem could be?