F250 2WD Dana Diff 08/1986-07/1992 – NS987 (Front). F250 2WD Ford Diff 08/1986-07/1992 – NS987 (Front). F350 2WD R/H Side 1981-01/1982 – NS987 (Front). F350 2WD L/H Side 1981-01/1982 – NS987 (Front). F350 2WD R/H Side 01/1982-04/1984 – NS987 (Front).