 The chassis was derived from the T1E2 chassis , an earlier version of the M13 . Based on an M3 Half @-@ track chassis , it replaced the M13 MGMC half @-@ track after early 1944 . As aircraft became more advanced , the usefulness of the M16 was reduced . In the Korean War , it was relegated primarily to the ground @-@ support role , being put out of service in the U.S. Army in 1951 . 
