Texas State Highway 310

Its northern terminus is US 175; its southern terminus is Interstate 45. The northern section is a freeway to Overton Road, just south of the Trinity River bridge, and a surface street from there to its southern terminus. The southbound bridge is the original simple steel girder bridge from abutment to abutment while the northbound is newer and largely precast concrete - the only steel girders are the longer spans directly over the river. The southbound bridge was repainted by CEKRA for TxDOT in late 2015.

SH 310 north of Loop 12 (along with the northern portion of US 175 with which it connects) was co-named the S.M. Wright Freeway after a local minister. It is technically also referred to as Central Expressway, as the original US 75 was given this name. In practice, Dallasites refer to the current US 75 (the portion north of downtown) as Central Expressway and the decommissioned US 75 (the portion south of downtown) as the S.M. Wright Freeway.

Through southern Dallas, Interstate 45 (also named the Julius Schepps Freeway) has replaced State Highway 310 as a through route. However, as I-45 is completely elevated between downtown and the Trinity River, during freezing rain events it is virtually impassable, whereupon it is closed and traffic is diverted onto State Highway 310.[2]

An earlier SH 310 was designated on February 20, 1939 from SH 29 to the Lockhart Recreation Center.[3] On September 26, 1939, SH 310 was cancelled and transferred to PR 10. The current SH 310 was designated on January 28, 1987, replacing part of US 75 from US 175 south to I-45. On April 29, 2013, SH 310 was extended north from US 175 to I-45, replacing part of US 175, which was designated to be rerouted on a more direct route west to I-45. The rerouting of US 175 is currently under construction.[4]

The entire route is in Dallas County.

Location	mi	km	Destinations	Notes
Hutchins	0.0	0.0	I-45 south	Southern terminus, interchange, exit 275 on I-45
	0.5	0.80	I-20 east	Interchange, exit 474 on I-20
Dallas	2.2	3.5	Simpson Stuart Road	At-grade intersection
	3.5	5.6	Loop 12	Interchange
	4.3	6.9	Illinois Avenue	At-grade intersection
	5.2	8.4	Overton Road	At-grade intersection, south end of freeway
	5.9	9.5	Lamar Street	Northbound exit and southbound entrance
	6.4	10.3	Municipal Avenue / Lamar Street / Haven Street
	6.6	10.6	US 175 east – Kaufman	Southbound exit and northbound entrance
	6.8	10.9	US 175 west – Dallas	Northern terminus
1.000 mi = 1.609 km; 1.000 km = 0.621 mi       Incomplete access