[2] For the remainder of its route, SH-128 runs mostly parallel to a spur from the Kansas City Southern rail line; the road crosses the tracks once, just east of the Heavener city limit.

At the highway's approximate midpoint, the route passes through unincorporated Forrester.

From here, SH-128 follows a generally east-northeast heading before crossing the state line into Scott County, Arkansas.

The road continues east toward Bates as Arkansas Highway 28.

Initially, it did not connect to Highway 28 upon crossing the Arkansas state line.