The portion of SR 4 between High Street (SR 129) and North Fair Avenue in Hamilton is designated as the "Firefighter/Paramedic Patrick Wolterman Memorial Highway",[4] in honor of a firefighter/paramedic for that city who died December 28, 2015, while battling an intentionally-set house fire.

The two men who started the blaze were convicted of murder and arson in November 2017 and sentenced to life in prison.

The route splits as a freeway again, until it becomes a one-way pair of surface streets in downtown Springfield.

North of Springfield, the route is primarily a two-lane rural highway until its end in Sandusky.

[6] In 1959 alignment from Dayton to Springfield rerouted and upgraded to freeway; segment through Fairborn around Wright-Patterson Air Force Base designated as SR 444.

The intersection, which is uncontrolled, is along a high-speed portion of SR 4 that is near-expressway in character; additionally, the median is not wide enough to allow longer vehicles such as tractor-trailers to wait there safely before making a left turn (north) from New Carlisle Pike onto SR 4.

Fixes for the problem intersection, all rejected, included adding lights and signage; closing the intersection; adding a traffic light; constructing a roundabout; adding an overpass; requiring traffic from New Carlisle Pike to northbound SR 4 to instead travel southbound to the SR 235/Chambersburg Road interchange, exit and re-enter northbound; and rerouting New Carlisle Pike to Chambersburg Road.

The first, a restricted crossing U-turn (RCUT) (also known as a superstreet), would prohibit left turns from New Carlisle Pike or Lower Valley Pike, and cross-traffic between the two; those movements would be accomplished via right turns onto SR 4, followed by designated median U-turns.

The second alternative, sometimes called a "basic RCUT", is similar to the first alternative, but would additionally prohibit left turns from SR 4 to New Carlisle Pike and Lower Valley Pike; those movements would be accomplished via median U-turns, followed by right turns.

[19][20][21] In the 1990s, the Butler County Transportation Improvement District (BCTID) was formed to help address traffic congestion along the fully two-lane bypass route.

[15][22] Construction of the expanded roadway finished in August 2012 on time and on budget, at a cost of $22.8 million.

[22] As of April 2013, it was reported that the majority of motorists in the area did not approve of the new design, with some avoiding SR 4B entirely.