S5 Alternator bearing size?
 

Im mostly certain that the bearings in my alternator are starting to go due to the air pump belt removed and more load put on the alternator pulley. Theres a loud metal grinding/squealing sound once the rpms go around 1k. It goes away at higher rpms so probably the bearing starts to lock up when theres not as much force. I took off the belt on the alternator and I used a stethoscope to listen to all the pulleys/bearings just to make sure. The only kind of noise I hear from is the alternator bearing when I push down a bit while spinning the pulley.

What size are the front and rear bearings in the S5 alt?

I dont have an impact wrench and air compressor to get the pulley off so does anyone know how much in general it would be to have a shop replace them?

I've also ordered a dual belt pulley kit and the bracket kit from banzai which will be coming in today.

Removing the air pump had no effect on the alternator at all, only the waterpump.
In fact, your new double alternator pulley is purely for the benefit of the waterpump as well and is a detriment to the alternator (extra belt/load cantilevered even further from the bearing).

You can avoid all of this nonsense by moving to a side mount alternator.
You use one belt only and still get better "wrap" on the waterpump pulley than the other method.

Well I mean with the air pump belt off, I tightened the alternator belt more to try to prevent any slipping if any occurred. Currently I just have the alternator and power steering belt on.

Havent heard of the side mount but I just looked it up. It seems like a more logical way if I wanted to give up my ps and a/c. I like the idea of the side mount though.

Alright then, if the side mount is out, it would make more sense from an engineering standpoint to add an idler pulley where the airpump used to be and run the extra belt just like it used to.

That gives you the extra drive on the waterpump pulley you want while avoiding the extra stress on the alt and the problem of matching belt length on a dual pulley.

I dont know how I would put an idler pulley there since I have the adjuster bolt snapped where you thread the bolt in.

I tried to find information of the bearing size in the alternator but I had no luck finding anything.