Suspensions with leading arms normally have the arms at an "up" angle
(hub higher than arm pivot), perhaps because that rides better than leading arms pointing down, although we have had detailed discussions of the various configurations. Early Bolers had "up" arms to reach the desired low ride height while still fitting the axle
assembly under the frame.
Most vehicles - cars, trucks, and trailers - have studs fixed in the hub, and wheels held on by nuts. All types of vehicles are occasionally found with threaded (tapped) holes in the hub instead, and bolts holding the wheel on
. Dexter (the most common source of trailer axle
components) offers both options. This came up in the topic Dexter & AL-KO hub interchangability
. The use of tapped hubs and bolts is not unique to Bolers, and I don't think it's common for them either. Mine has studs.
Well, that's some words... maybe not wisdom!