Ok, maybe I should have said outter bearing. (you know the one closest to the seal)
It all started when the synthetic gear oil got water in it. The synthetic oil broke down and mixed with the water causing a sludge.
I didn't expect the pinion bearing was going to last much longer. I only hope it didn't damage the pinion gear.
I want to look into making a oil pump to help get oil to the pinion bearings.