Yamaha, 25-60HP - 3 1/2 Gearcase - 13 tooth spline, T25HP 2010-, F30 (4-Stroke) 2001-05, 2015-, 40HP (C40) 1984- , F40 (4-Stroke) 1999-, 48HP 1995-2000, 50HP (Not T50) 1984-, F50 (4-Stroke) 1995-, 55HP 1976-95, 60HP 1976-91, F60 (4-Stroke) 1999-