I’ve read the same about the original design with lower hinge taking the major portion of the weight load. With the door open, doesn’t the top hinge bear the same weight load, though in opposite direction, as that on the bottom hinge? Ie, the top hinge is in tension while the bottom hinge is in compression. Yes, I’m sure there is a reason why they didn't design the lower hinge to be bushed. Hopefully someone can help me understand,
Good question
only reason i can think of are, the detent springs, or being lower possibly they are more prone to collecting debris
I will say in ~ 25 years of business / inspections the Lower hinge has always been the one that wears more than the top, 90% of the time excluding a few Mfr's that tried using PLASTIC bushings on the top hinge
