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 September 30, 2002 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

                                                     November 14, 2002