I replaced the Grommets on the “top” motor bracket. The parts diagram for my model only shows one but there is both top and bottom grommet. Only ones I ordered so replaced the top one as it appeared more worn out. Did not need the small bumper (different part) as it doesn’t seem to make contact with the motor.
Note: replaced the motor and fan one year ago, the original was 17 years. It would have been good to know this was potentially wearing out but I did not think to look at it …and it didn’t make a noise then …. Would have prevented this second repair. Still, easy fix.