tbran
Guest
We had one do this - found no balance drillings in the sheave - thus suspected it was the problem - replaced and no problem since. We did replace with latest n's. 71370583 71370165 as coupling and flex plate. The rear PTO shaft has been updated down through the years. last R72 models had shaft 71376945, pulley 71376947 and 71376948 brg carrier. We had to do some modification but customer wanted latest,greatest etc. Still think the sheave was the problem as this is the only unit we had problems with. Back axles in RWA we have had no problem with - 2wd units are not as heavy - if it makes one feel any better a large farmer close to our dealership was driving his new Green Machine from the first field to the next- the rear axle snapped (RWA) and the driver ended up at the bottom of a ravine (gulley) after several flips. He was shaken but ok. Speaders are a fact that brgs and flanges will loosen - thus the advent of hydraulic spreaders. We do install round flanges instead of trianglular and install rubber flap to keep material from building up and deteriorating brg seals. Failed gears are rare here as are feeder shafts although they have occured. Newer large shafts and sprockets to match went in at '98 year model me thinks. Best o luck.