Take I-79 SOUTH from Pittsburgh to I-64 WEST to HUNTINGTON in Charleston, WEST VIRGINIA.
Take I-64 WEST across to I-44 WEST to TULSA via I-255 SOUTH (EXIT 7 off I-64 in ILLINOIS, SECOND RIGHT) and I-270 NORTH (EXIT 5B off I-270 in MISSOURI to get onto I-44 WEST to TULSA) to bypass ST. LOUIS.
Take I-44 WEST to I-40 WEST to AMARILLO via the KILPATRICK TURNPIKE (toll) to bypass OKLAHOMA CITY. To bypass TULSA, take the CREEK TURNPIKE (toll).
Take I-40 WEST across to I-15 SOUTH at END I-40 in BARSTOW, CALIFORNIA.