I have a 1998 Gmc Sierra Ext. Cab 4x4 with 91,000 miles and a 5.7 v8. With a BRAND new battery and a BRAND new alternator but something is making the battery run down i would have to jump it off EVERY day. But today when i tried to jump it off I had 14 volts of battery which is what it should have. But it still wouldn't crank it will only turn over when i try and start it the battery gauge needle went down and the the oil pressure gauge needle went up. What could be causing this??
