Oklahoma State Highway 18

US-177 runs roughly on top of the previous SH-18 between Dickson and Asher, Oklahoma, therefore only a few small segments of the original highway remain through that stretch.

Old SH-18 north of Asher

Much of the old highway from south of Asher to Tecumseh, Oklahoma still remains. Remnants of the old highway begin north of the curve just before US-177 junctions with SH-3W, south of the Canadian River. SH 18 (now US-177) originally continued straight ahead and then turned slightly ahead of where US-177 does now. The existing old highway runs parallel west of US-177 for about a mile, before terminating short of the Canadian River. Originally, the highway continued straight for about another 0.5 miles (0.80 km) (taking it over the river) before veering east and then back north. The cement supports of the old bridge can still be seen if you look westward at the north and south banks, while crossing the Canadian River bridge (coincidentally, the bridge may return to that location if reports of replacing the Canadian River Bridge are true). Much of the section after the river and before the highway intersects with SH-39 has been lost due to another bridge being removed.

The existing highway picks up again after a second removed bridge and 0.7 miles (1.1 km) before intersecting with SH-39 south of Asher. The highway continues north through Asher (here named Division Street) for 1.5 miles (2.4 km) before again veering east and then once more travels roughly north. The road is mostly intact except for a small area near Pearson, Oklahoma where it is rerouted to cross SH-59. North of Pearson is the Salt Creek Bridge, a 120' long OSHC standard design, built in 1930.

Salt Creek Bridge

Near Macomb, Oklahoma the old highway again travels parallel and very near to US-177. The highway is interrupted once because of the removed Little River Bridge before reaching the Brooksville, Oklahoma area. Here, the highway is slightly rerouted to cross US-177 (veering west) and then heads north toward Tecumseh. The designation "Old 18" ends here as the highway has been absorbed into city streets, although it appears the highway traveled east down what is now Highland, then north on Broadway and continued to Shawnee on what is now Gordon Cooper Drive/Beard Street. Beard Street intersects with Farrall Street in Shawnee, which is the current SH-18. East of this intersection, SH-18 ends and loops into US-177. West of the intersection, Farrall veers north and merges into Harrison Avenue. At this point, 18 continues as a current state highway.

• There is roughly 20 miles (32 km) of drivable road designated "Old 18" between US-177 / SH-3W Junction south of Asher and Tecumseh, although it can not be driven continuously.
• The longest uninterrupted stretch of Old 18 is about 14.5 miles (23.3 km), between Asher and the Little River near Brooksville.
• Except for a 1½ mile repaved stretch through Asher, Old 18 shows its original concrete construction (although heavily patched with pavement).
• At its furthest, Old 18 rests 1½ miles east of its replacement, US-177.
• The curved edges and poor drainage of the highway can make it dangerous during heavy rain as it greatly retains water.
• The original Canadian River Bridge south of Asher was in use from 1921 to 1967. It has since been removed.