While some people will tell you that all bearings are the same, this just isn't the case. All bearings have a manufactuer name and number on them, so it appears that the bearings would be easy to copy. John Deere bearings have a few extra numbers that are intentionally left off of the bearings they order from the bearing companies. These extra numbers tell the company what tolerances to build the bearing to, what type of grease to fill the bearing with, even how much grease they want in the bearing when it is assembled. You can't go wrong with Genuine John Deere Parts. Whats the value in saving a few bucks for inferior parts that will wear out quicker.