The
    transmission case is gravity cast in a no-bake sand mold with multiple, complex
    cores.    There are two critical features in the transmission case --
      - The spline section at the bottom of the internal barrel.
 
      - The flat base plate of the transmission case which
        requires numerous bolt holes for attaching the fluid valves.
 
     
    Both of these features are critical mating surfaces; they
    required extensive machining and need to be free of voids and defects. 
         ->  The
    spline is the more critical feature.  | 
    
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