Exhibit 99.1


                            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  quarterly  report  of Terex  Corporation  (the
"Company")  on Form 10-Q for the period  ending March 31, 2003 as filed with the
Securities and Exchange Commission on the date hereof (the "Report"),  I, Ronald
M.  DeFeo,  Chairman,  President  and Chief  Executive  Officer of the  Company,
certify, to the best of my knowledge, pursuant to 18 U.S.C. ss. 1350, as adopted
pursuant to ss. 906 of the Sarbanes-Oxley Act of 2002, that:

        (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/ Ronald M. DeFeo
                                              Ronald M. DeFeo
                                              Chairman, President and
                                              Chief Executive Officer
                                              Terex Corporation

                                              May 15, 2003










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