Answer: 2,314 miles (3,725 kilometres) taking this route:
Take HIGHWAY 401 WEST from Toronto to HIGHWAY 402 WEST to SARNIA at EXIT 183 near London.
Take HIGHWAY 402 WEST to Sarnia where you will cross the BLUE WATER BRIDGE (toll) into PORT HURON, MICHIGAN, U.S.A.
Once you have crossed the bridge and the border, follow signs to I-69 WEST to LANSING. Take I-69 WEST and SOUTH (changes direction past Lansing) all the way down to I-70 WEST to ST. LOUIS via I-465 SOUTH (and WEST) around Indianapolis (EXIT 0 off I-69 in INDIANA to get onto I-465 SOUTH; EXIT 9 off I-465 to get onto I-70, follow signs to I-70 WEST to ST. LOUIS).
Take I-70 WEST to I-44 WEST to TULSA via I-270 WEST (and SOUTH) around St. Louis (EXIT 5B off I-270 in MISSOURI to get onto I-44 WEST to TULSA).
Take I-44 WEST down to I-40 WEST to YUKON and AMARILLO via KILPATRICK TURNPIKE (toll) around Oklahoma City, OKLAHOMA. To bypass Tulsa, take the CREEK TURNPIKE (toll).
Take I-40 WEST across to I-17 SOUTH to PHOENIX at EXIT 195 off I-40 in Flagstaff, ARIZONA.