Does anyone know what #3 is called and where I might be able to find one? I'm trying to replace my radius arm but can't seem to get the nut to break loose that's holding the spring seat. So if it breaks off I'd like to know I can replace this bolt.

 

Its called Radius arm bolt, seen here: https://www.fordpartsgiant.com/parts...0A4LD&filter=()

Ford -390386-S2

1983 to 1997 Rangers used the same bolt