This report presents research in substitution technology for a chromium-free (cr-free) alternate for 8620 steel. A cr-free steel composition developed in an earlier program was melted and cast, processed into carburized gears, and evaluated in comparison with an 8620 steel control group and an existing performance data base. An evaluation of processing characteristics indicated that the cr-free steel could be substituted for 8620 in a gearing application with no change in process parameters. The performance of the cr-free steel in the gearing tests was equivalent to, or slightly better than, both the 8620 control group specimens and the existing data base. Metallurgical characteristics of the cr-free and 8620 steels were examined, and only minor differences were identified. Results from this investigation indicated that the cr-free steel composition should be a suitable alternate for 8620 steel in a wide range of heat-treatable applications.