By April 1939, it had been extended eastward to end at Asher.

Due to the impending war, he was originally only offered a year's contract but, after negotiation, this was extended to end in March 1941.

By the middle of 1936, the highway was extended northward to end in Lansing.

The west end was extended in 1936 to end at the Livingston-Oakland county line.

By the middle of 1936, the highway had been extended northward to end at a junction with M-46 in Saginaw.

Within its first decade, M-48 was extended to end at a point north of Newberry.

In 2002 the net-metering scheme was extended another four years up to end of 2006.

In 1963, the route was extended east to end at the State Mental Hospital.

The trial was then extended to end on Saturday.

On April 1, 1936, the highway was extended east to end at the Arkansas state line.