alternator or somethink bigger
 

been gettin noise from engine like a grinding took it to a garage he said alternater bearings goin noise is gettin louder hope it ent the bottom end?

I imagine if you took off the alternator belt you would be sure?

big ends usually knock when they are letting go.

what do i do then just take alternater belt of and run it with it off is it easy to take off

Remove the alternator belt and run with it off. Do it for just a minute or two since during this time your battery is not being charged.

You need to loosen the alternator tensioner by loosening two bolts, lower the alternator and then slip the belt off.