This is sort of an odd thing that happened in the past. My friend had a 1955 Cub with a Cub 22 mower. We always kept it greased, we greased the long mower shaft liberally, at both grease fittings. The grease would always work out the rear when he was mowing, and get on the pulley. After several years of use the front bushing started getting noisy, lots of banging sounds when mowing. We took it apart, and the front bushing was dry, no grease evidently. It ruined the bushing and the shaft. We had to replace both. The grease we put in the grease fittings went to the rear, but not to the front bushing, which is just an inch or 2 from the front grease fitting.
My friend though it might be the direction the mower shaft turns made the grease go one way, to the rear. I don't know if other people have that happen or not. Anyway, be sure both your bushings are getting grease.
