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                                                                  EXHIBIT 3.1(I)

                        CERTIFICATE OF AMENDMENT TO THE
                            RESTATED CERTIFICATE OF
                    INCORPORATION OF TENNECO AUTOMOTIVE INC.

     Tenneco Automotive Inc. (the "Corporation"), a corporation organized and
existing under and by virtue of the General Corporation Law of the State of
Delaware (the "DGCL"), does hereby amend the Restated Certificate of
Incorporation, as amended, of the Corporation.

     The undersigned hereby certifies that this amendment to the Restated
Certificate of Incorporation, as amended, of the Corporation has been duly
adopted in accordance with Section 242 of the DGCL.

     Subsection A of Article FOURTH of the Corporation's current Restated
Certificate of Incorporation, as amended, is hereby amended to read in its
entirety as follows:

        "FOURTH: A. The total number of shares of all classes of stock
        which the corporation shall be authorized to issue is
        185,000,000 shares, divided into 135,000,000 shares of common
        stock, par value $.01 per share (herein called "Common Stock"),
        and 50,000,000 shares of preferred stock, par value $.01 per
        share (herein called "Preferred Stock")."

     THE UNDERSIGNED, being the Senior Vice President and General Counsel of the
Corporation, for the purpose of amending the Restated Certificate of
Incorporation, as amended, of the Corporation pursuant to the DGCL, does make
this amendment to the Restated Certificate of Incorporation, as amended, of the
Corporation, hereby declaring and certifying that this is my act and deed and
the facts herein stated are true and accordingly I have hereunto set my hand as
of this 9th day of May, 2000.

                                          TENNECO AUTOMOTIVE INC.

                                          By: /s/ TIMOTHY R. DONOVAN
                                            ------------------------------------
                                          Name: Timothy R. Donovan
                                          Title:   Senior Vice President and
                                          General Counsel