I have a new Grasshopper 725K2. The tractor manual says to grease the drive shaft every 8 hours. I easily found all other lube sites, but cannot for the life of me find the drive shaft one. The only bearings I see on this short shaft look to be sealed bearings. The tractor manual shows the "drive shaft" as being the shaft coming out the front of kohler 25hp engine that runs the two pulleys for each drive wheel motor. The deck manual calls the sliding zert below feet platform a "power shaft". Am I just not seeing the zert because it's hidden or right in front of my face? Thanks for any and all help. PS. I mow around many trees and obstacles. My 8 hour mowing days just went to 1.5. Unbelieveable machine!! NW IN.