A couple of years ago after mowing one of our fields I noticed Hyd oil pooling beneath my B2620, Oh "you know what". Ok, its a good thing I kinda like tearing stuff apart, as the tallgrass had wrapped itself around both ends of the propeller shaft destroying the bearing seals. Of course the only way to replace the propeller shaft bearing seals, was a good old fashion tractor split. So I spent several days replacing the seals. Not wanted to repeat this PIA I decided to try this mod. After several years of mowing 3 foot tall grass there has been no problems.