X0202 4 2005-09-13 0 0000110430 FRONTIER OIL CORP /NEW/ FTO 0001189449 WILLIAMS W REED 10000 MEMORIAL DRIVE, SUITE 600 HOUSTON TX 77024-3411 0 1 0 0 EVP-Refining & Marketing Oper. Common Stock 2005-09-13 4 M 0 100000 8.325 A 204648 D Common Stock 2005-09-13 4 S 0 84300 40.22 D 120348 D Common Stock 2005-09-14 4 S 0 15700 40.04 D 104648 D Employee Stock Option Plan 8.325 2005-09-13 4 M 0 100000 8.325 D 2003-02-20 2008-02-19 Common Stock 100000 150000 D Ending balance of securities beneficially owned reflects two-for-one stock split June 17, 2005. W. Reed Williams 2005-09-15