I have a 1999 Blazer Trailblazer. I started hearing a squeal or hum type noise coming from the passenger side of the engine. 2 days later i was driving home and the battery slowly started to drain. The power would go down when i turned or hit the brake and up slightly when i accelerated. By the time I got home it was completely dead. I'm thinking its the alternator but not sure. Any ideas?

 

Sure sounds like the alternator. If you remove the belt, how smooth does the alternator turn?