In getting ready for snow, I had trouble attaching the driveshaft that is attached to the blower, to the tractor. I noticed this threaded "lock" on the driveshaft. Once loosened, the driveshaft was able to slide and connected to the Quick Hitch in a snap. My question is, I have never had this "lock" on any of the other driveshafts for this blower, and should I operate with it locked? It appears the dealer had it locked, as I didn't adjust it when I took the blower off this spring. It just seems the driveshaft should slide in and out, especially when raising and lowering the blower? Thanks!