All GM NV273 Transfer Cases have fixed yoke type input and front/rear output shafts. Front output shafts were built in an early and late version. While they are interchangeable if you also replace the sprocket snap ring, I feel the early Front Output Shaft is preferred for competition or really heavy-duty use, due to the full length spline and the early Sprocket Snap Ring is significantly thicker than the one used with the later shaft.












