It appears Ford is using self-leveling shocks like Nivomat. It's a completely self-contained unit with no additional external hardware needed.
I had a similar setup on my 2001 Suburban with the ZW7 Premium Smooth Ride Suspension.
It's a great shock, works as advertised, but expensive to replace. IIRC, I paid $357 a piece for replacements.
The upside is that it keeps you level, regardless of load. The downside is that you're more prone to overloading, since there's no sag to the rear end. I'm really surprised these haven't been picked up by more manufacturers.
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