EXHIBIT 99.1

    WRITTEN STATEMENT OF CHIEF EXECUTIVE OFFICER AND CHIEF FINANCIAL OFFICER
                             PURSUANT TO SECTION 906
           OF THE SARBANES-OXLEY ACT OF 2002 (18 U.S.C. SECTION 1350)


The undersigned, the Chief Executive Officer and the Chief Financial Officer of
Wabash National Corporation (the "Company"), each hereby certifies that, to his
knowledge, on May 13, 2003:
(a)      the Form 10Q, Quarterly Report Pursuant to Section 13 or 15 (d) of the
         Securities and Exchange Act of 1934 of the Company for the quarter
         ended March 31, 2003 filed on May 13, 2003 with the Securities and
         Exchange Commission (the "Report") fully complies with the requirements
         of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and
(b)      information contained in the Report fairly presents, in all material
         respects, the financial condition and results of operations of the
         Company.


                                            /s/ William P. Greubel
                                            ----------------------
                                            William P. Greubel
                                            Chief Executive Officer
                                            May 19, 2003

                                            /s/ Mark R. Holden
                                            ------------------
                                            Mark R. Holden
                                            Chief Financial Officer
                                            May 19, 2003