A previous highway, also called SH 40, existed from March 17, 1919 until September 26, 1939, and ran from the
Oklahoma state line north of
Gainesville down through
Denton,
Dallas and
Beaumont before ending in Sabine Pass. On March 18, 1919, a
spur route,
SH 40A that went from Denton and ended in
Fort Worth was designated, so SH 40A and the route of SH 40 north of Dallas replaced
SH 16. On August 21, 1923, this spur had become an extension of
SH 10. That same day,
SH 40 was truncated to Voth (north of Beaumont), with the section from Voth to Beaumont already part of
SH 8 and the section from Beaumont to Sabine Pass cancelled. SH 40 was rerouted over a portion of
SH 37 between Rusk and southeast of Lufkin, while the old route was either cancelled or transferred to SH 37. On May 22, 1933,
SH 40 Spur was created to
Baxter. On January 24, 1938,
SH 40 Loop was designated to
Keltys. On April 19, 1938,
SH 40 Bypass was designated from SH 40 to SH 114. On June 21, 1938,
SH 40 Spur was designated to
Forest. The Gainesville to Dallas portion became
US 77 in 1929. In 1932, the Dallas to
Jacksonville stretch had become part of
US 175. The last remaining portion of old SH 40, Jacksonville to Port Arthur, became part of
US 69 in 1934. On September 26, 1939, SH 40 was cancelled in favor of these US Highways. The
SH 40 Loop and
SH 40 Spur routes were renumbered as
Loop 12 (Dallas),
Spur 29 (Forest),
Loop 36 (Keltys), and
Spur 65 (Baxter).
SH 40A was a spur route proposed on September 16, 1926, going from St. Augustine south to
Zavalla. This route was actually designated as SH 8B instead(now
SH 147). Interstates
35E and
35W roughly follow the old SH 40 routes from Dallas and Fort Worth, respectively, to Denton, and the old route from Denton north is approximated by
Interstate 35. ==Major intersections==