You can see the piling of metal shavings underneath the sprocket. This is a clear indication that the inner bushing / sleeve has been wearing away and is about to fail. You can also see the Jenga type looking assembly. There is no straight uniform position of the drive sprocket that is attached to the stem. This needs to be replaced for the door to work as the manufacture has suggested.

After the gear assembly has been replaced and fully tested. You can see the nice and true uniform looking assembly. This is how the drive sprocket should look. All irregular noises have been removed from the motor and the system has recovered some of the original smoothness that the homeowners forget they once had.

Before repairs of the gear assembly. The view of the metal shavings is quite apparent. This is not a proper looking drive sprocket that is able to drive the motor a long duration.

Inner view of the operator that has a gear that has seen better days. The gear nylon (teeth) are eaten away as well. The main drive shaft you can see is not sitting perfectly true in the middle housing. This bushing that has been grinding away has also been dropping metal bits on the inner white gear. You can see black coloring and little bits coming off the gear.

Beautifully looking replaced gear kit for the LiftMaster Operator. You can see the perfect orientation of the sprocket. This operator is ready for use.