S60 non-turbo has 130,000 miles that started making a whining noise. It only does it when driving down the road after about 15-20 minutes of driving. I also noticed this when I come to a red light at idle the rpm will go up and down from about 500-1000 rpms and the light will dim up and down.

I heard it could possibly be a bearing in the alternator does this sound reasonable?

Also when I go above 55 the front will start to shake could this be just wheels out of balance.

Thanks for the help.

 

Sounds like the alternator needs to be replaced, although it wouldn't cause shaking at any speeds. That may be related to wheel balance or a bad drive shaft.
Have you done the timing belt? I heard that it or it's components can make noises when worn and it is in the same general area as the alternator and the serpentine belt tensioner.

 

volvos eat voltage regulators. it's that black plastic pack on the back of your alternator. replace your alternator. as far as the vibration, that's probably your tires way of singing a pretty song to you...."change me". check the wear-bars, it may be time. could also be a broken or separated belt inside one of the tires itself. look for a bulge on the side wall of the tire, or follow your tread lines and look for any cracks that run the entire diameter of the tire. good luck.

 

Rotate ur tires front to rear if still in good condition and see if vib. goes away. It;s also possible ur tie rods r worn out.