Today I've been hearing sorta a squeeling noise from under the hood at rpm of oh say about 3500. And later I noticed my voltage gauge was all the way to the top. I've had this alternator in for about 4 months now, no problems. i looked under the hood and nothing looked to be wrong. Then the voltage gauge was kinda jumpin around, low-to high....any ideas? oh and my friend drove it and he kinda drives a little harder than I...