Practically "identical" to the 1904-built 3671-3675 0-6-0's, the 3731 class engines differed in only the most minute of dimensions, and they were 5800 lbs heavier. Like their older sisters, the 3731's had an above-the-driver fire box. 3731 sold Nov 1948 Republic Steel, B'ham, AL 3732 retired Feb 1947 3733 retired Sept 1947 3734 sold Mar 1949 Republic Steel, B'ham, AL 3735 retired Jul 1950 3736 retired Mar 1950 3737 retired Mar 1950 3738 retired Jul 1950 3739 sold Jan 1952 Delta Valley & Southern, Elkins, AR 3740 retired Apr 1951