Thrust Bearing 02-80-1800

-Initial problem was no speed change and a rattling/grinding noise
-Opened up for inspection. Felt the grease pack in the gear box and it was gritty, removed and cleaned out grease. There was a lot of metal debris in the grease.
-Disassembled the gear train. High torque gears were in very bad shape. Found pieces of a thrust bearing wedged in the teeth. (Likely the cause)
-I looked up the parts online and found them here. Ordered and waited for them to arrive.
-One intermediate shaft was a bit of a delay but once available, the entire shipment was sent.
-During reassembly, I found that I missed one of the thrust bearings and had to order one separately. It arrived in a couple of days and I was able to reassemble and re-pack the grease in the gear box.
-Drill is now back in service, sounds good and gear change is once again possible.
(Milwaukee Mag Drill)