My 04 1500 has been making a squealing noise lately. It isn't noticeable at idle, only during acceleration and driving. I say it that way because I can give it gas while in park and still hear the sound. A mechanic stated I needed a new alternator, which I replaced. This did reduce but not completely eliminate the noise. This has been happening for about 2-3 weeks. Any ideas or suggestions?

 

A squeal like you mention is almost always the belt, or something run by the belt. At least that narrows your search down.
Check your tensioner, has it run full travel?
Are all of the pulleys lined up and running true?
Is your belt in good condition? Do you see any score marks or cracks?

 

Yeah, check your tensioner and and idler pulleys