FIFTH MODIFICATION AGREEMENT
BY THIS FIFTH MODIFICATION AGREEMENT (the "Agreement"), made and entered into as of the 15th
day of December, 2003, WELLS FARGO BANK, NATIONAL ASSOCIATION, as administrative agent (the
"Administrative Agent") for the Banks listed in the hereinafter defined Credit Agreement (the "Banks") and as the
Issuing Bank and the Swing Line Lender, and KNIGHT TRANSPORTATION, INC., an Arizona corporation
(the "Company") and all present and future Significant Subsidiaries of the Company (with the Company, the
"Borrower"), in consideration of the mutual covenants herein contained and other good and valuable
consideration, the receipt and sufficiency of which is hereby acknowledged, hereby confirm and agree as follows:
SECTION 1. RECITALS; ACKNOWLEDGEMENTS.
1.1 The Borrower and the Administrative Agent and the Banks entered into that Credit Agreement dated April 6,
2001 (as amended from time to time, the "Credit Agreement") to provide financial accommodations to the
Borrower as provided therein. The Credit Agreement was previously amended by that Modification Agreement
dated as of June 5, 2001, that Second Modification Agreement dated as of November 19, 2001, that Third
Modification Agreement dated as of February 13, 2003, and that Fourth Modification Agreement dated as of
September 15, 2003.
1.2 Borrower and the Administrative Agent, with the consent of the Banks, desire to modify the Credit
Agreement as set forth herein.
1.3 All undefined capitalized terms used herein shall have the meaning given them in the Credit Agreement.
SECTION 2. CREDIT AGREEMENT.
2.1 The following definitions in Section 1.1 of the Credit Agreement are hereby amended to read as follows:
"Loan Documents" shall mean this Agreement, the Notes, the Security Documents and all other documents,
instruments and agreements of every kind and description at any time undertaken by any Person for the benefit of
the Banks in connection with the Loans.
"Maximum RLC Commitment" shall mean $1