Combines Why did they do thisIJ

The manual says "Steel flight assemblies can be installed on the conveyor chains. The steel flight assemblies are recommended for heavy crops such as corn and for operation in wet and muddy conditions. The steel flight assemblies help to keep dirt from caking in the grain and tailings elevators. Two steel flight assemblies per chain, equally spaced, are recommended for best results."

i had to change one on non gps 2188. installed rubber. some engineers must stay awake nights thinking of these things when things have been working good for 25 years.

That is exactly what they are used for. If you do experience wet conditions with mud going into the machine, you will not get 50ft. without them. I don't know on your particular application but on the old Gleaners, it was a life saver, and even the old 55 JD. They never came off or caught on anything. If you don't have screens on your clean grain or return, you really don't need them unless you have a build up. Maybe you could revamp it and add bolts or something so you don't lose them. My suggestion since we went to a 1660 is to install the nylon paddles! They key is adjustment though. Good luck!