LiftMaster 41A4836 Drive Sprocket Kit

My garage door opener was making a loud scratching metal on metal noise. The roller bearings were worn flat once replaced everything was back to smooth operation a cheap fix to replacing the whole unit. One thing I noticed about the kit it does not have two cupped washers but one. When I replaced the original parts it had two had to reuse the one of the old ones. There is no manual for this repair. Don’t know if this is a mistake on the packaging because it does have two spring washers that sits in the cupped washers but it only has one hmmmmm.