I bought an '02 Trailblazer back in September. It has always made a loud humming noise when I rev up the RPM. However, it has only just started to make a very loud squeaking noise when I accelerate, at any speed or RPM. My dad looked at it and believes the problem to either be from the fan clutch or the water pump. There is a bit of more movement in the fan than I think there ought to be. Anyone have any ideas?