The upper bearing in your gearcase is definitely going bad due to a failed main seal. To repair you have to replace gearcase W11255272 as the bearing isn't removable. Gearcase comes with a new main seal. You'll need Whirlpool spanner wrench TB123A to remove the tub nut. If you choose to live with the noise, eventually your washer will leak more and more and the washer won't fault out with various error codes.