1983-1989 GMC G2500. 1990-1991 GMC G2500 Engine: 4.3L V6;. 1990-1991 GMC G2500 Engine: 5.0L V8;. 1990-1991 GMC G2500 Engine: 5.7L V8;. 1992-1995 GMC G2500. Two-Way Check Valve. Vacuum Valve. Compatible Years: 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995.
