Originally Posted by Amen
Which the 3.75" 8 wall inner nut is. I contacted 6 different big truck/rv shops (and Northern/Harbor Freight/Rental shops) and none had one that big. Plus most online were 6 wall/point.
8-sided nut, I missed that point in your first post. That's really odd.
Did you get a chance to pull the "hub cover" and confirm, or are you going by what Hendrickson said?
I don't recall ever seeing an 8 sided wheel bearing adjustment nut before.