Have a 489 cone clutch diff. So any one can tell me will it work like the sure grip clutch diff. Talked to a old mopar guy here in Stark fl. He told me they ran the cone type diff and he never had a problem. When the got worn he put a shim behind the cone to rebuild it. They tested it and it worked like a new one. So any thought's on the subject would be grate. Just to inform me on my choice. Have looked every where for the clutch type or sure grip but no luck. Thanks Blue.