EXHIBIT 32.2


                            CERTIFICATION PURSUANT TO
                             18 U.S.C. SECTION 1350,
                             AS ADOPTED PURSUANT TO
                  SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002


     In connection  with the Annual Report of Smithway  Motor Xpress Corp.  (the
"Company")  on Form 10-K for the period ended  December 31, 2003,  as filed with
the Securities  and Exchange  Commission on the date hereof (the  "Report"),  I,
Douglas C. Sandvig, Chief Financial Officer of the Company, certify, pursuant to
18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley
Act of 2002, that to the best of my knowledge:

     (1)  The Report fully  complies with the  requirements  of Section 13(a) or
          15(d) of the Securities Exchange Act of 1934; and

     (2)  The  information  contained  in the  Report  fairly  presents,  in all
          material respects,  the financial  condition and results of operations
          of the Company.


                                  /s/ Douglas C. Sandvig
                                -------------------------------
                                Douglas C. Sandvig
                                Chief Financial Officer
                                March 30, 2004

A signed  original of this  written  statement  required by Section 906 has been
provided to Smithway  Motor Xpress Corp.  and will be retained by Smithway Motor
Xpress Corp.  and  furnished to the  Securities  and Exchange  Commission or its
staff upon request.