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                                                                    EXHIBIT 4.21

           FIRST UNION COMMERCIAL CORPORATION PROPOSAL EXHIBIT (NO. 1)

                                 USA TRUCK, INC.

                            PROPOSAL EXHIBIT (NO. 1)

The terms of this Proposal Exhibit are incorporated by reference within the
Proposal letter dated October 31, 2002.

1.       TYPE OF EQUIPMENT: New 400 Class Eight Sleeper Tractors.

2.       ANTICIPATED EQUIPMENT COST: Approximately $5,000,000.00.

3.       EQUIPMENT LOCATION: Continental United States.

4.       ANTICIPATED DELIVERY DATE: January 15th through December 15th, 2003.

5.       LEASE TERM: Forty-two (42) months.

6.       LEASE PAYMENTS: Lessee shall make forty-two (42) monthly payments, each
         payable in arrears, with the following monthly payment factors
         according to the month of equipment takedown:

<Table>
<Caption>
Month          JAN       FEB       MAR       APR       MAY      JUNE      JULY       AUG      SEPT       OCT       NOV       DEC
             -------   -------   -------   -------   -------   -------   -------   -------   -------   -------   -------   -------
<S>          <C>       <C>       <C>       <C>       <C>       <C>       <C>       <C>       <C>       <C>       <C>       <C>
Lease Rate      2.99%     2.97%     2.94%     2.91%     2.91%     2.89%     2.67%     2.64%     2.60%     2.61%     2.57%     2.54%

Payment
Factor       1.60616   1.60462   1.60307   1.60151   1.60150   1.60000   1.58687   1.58486   1.58285   1.58307   1.58112   1.57917
</Table>

         The lease rate in this transaction will float from the date of this
         letter until the equipment funding date, based on the change in either
         the 7 -1/2% Treasury Note's yield to maturity of 1.90% with a three (3)
         year remaining life and maturing February, 2005 or the one year LIBOR
         rate of 1.67%, as published in the October 31, 2002 edition of The Wall
         Street Journal and as published on the equipment funding date. The
         lease rate in this transaction will float up from the date of this
         proposal until the equipment funding date based on the change in either
         the above referenced Treasury Note's yield to maturity or the one year
         LIBOR rate, whichever is greater. The lease rate in this transaction
         will float down from the date of this proposal until the equipment
         funding date based on the change in either the above referenced
         Treasury Note's yield to maturity or the one year LIBOR rate, whichever
         is less. The lease rate shall be adjusted by .01% for each
         corresponding increase or decrease of .01% in the selected index. Due
         to the extended nature of the fundings quoted in this proposal, Lessor
         reserves the right to adjust the lease rate and payment factor in order
         to preserve its economic yield.

7.       PURCHASE OPTION: At the end of the lease term, Lessee shall have the
         option to purchase the equipment for its then Fair Market Value.

8.       TERMINAL RENTAL ADJUSTMENT CLAUSE: If the fair market value paid to
         Lessor by the Lessee or a third party exceeds or falls below forty
         percent (40%) of original equipment cost, the excess will be refunded
         to Lessee or the shortfall will be reimbursed to Lessor by Lessee
         through a rental adjustment.

9.       DEPRECIATION: For the account of the LESSOR and assumed to be three (3)
         year MACRS property.

10.      EXPENSES: Lessee shall bear expenses related to (i) preparation,
         negotiation and the finalization of documents related to the
         transaction, (ii) out-of-pocket expenses for lien searches, title
         searches and obtaining certified copies of charter documents and good
         standing certificates, (iii) title application, lien application and
         registration fees and financing statement filing fees, and (iv) similar
         out-of-pocket expenses.

11       INDEMNIFICATION: Lessee shall indemnify Lessor against all hazards,
         liabilities, claims, actions, contingencies and risk of loss caused by
         the acts and omissions of Lessee. Additionally, Lessee shall indemnify
         Lessor against the loss of tax benefits retained by Lessor caused by
         the acts and omissions of Lessee.