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                                                                  EXHIBIT 4.5(h)


                      FOURTH AMENDMENT TO CREDIT AGREEMENT

          FOURTH AMENDMENT, dated as of October 7, 2005 (this "Amendment"), to
the Amended and Restated Credit Agreement, dated as of December 12, 2003
(amending and restating the Credit Agreement dated as of September 30, 1999) (as
amended, supplemented, or otherwise modified from time to time, the "Credit
Agreement"), among TENNECO AUTOMOTIVE INC., a Delaware corporation (the
"Borrower"), the several lenders from time to time parties thereto (the
"Lenders"), JPMORGAN CHASE BANK, N.A., a national banking association (as
successor to JPMorgan Chase Bank), as administrative agent for the Lenders (in
such capacity, the "Administrative Agent"), and the other financial institutions
named therein as agents for the Lenders (in such capacity, collectively, the
"Other Agents").

                              W I T N E S S E T H:
                              - - - - - - - - - -

          WHEREAS, the Borrower, the Lenders and the Administrative Agent and
the Other Agents are parties to the Credit Agreement;

          WHEREAS, the Borrower has requested that the Credit Agreement be
amended as set forth herein;

          WHEREAS, the Lenders, the Administrative Agent and the Other Agents
are willing to agree to such amendment of the Credit Agreement, subject to the
terms and conditions set forth herein;

          NOW, THEREFORE, in consideration of the premises and mutual covenants
contained herein, the Borrower, the Lenders, the Administrative Agent and the
Other Agents hereby agree as follows:

          1. Defined Terms. Unless otherwise defined herein, capitalized terms
which are defined in the Credit Agreement, as amended hereby, are used herein as
therein defined.

          2. Amendments to Credit Agreement.

             (a) Section 1.1 of the Credit Agreement is hereby amended by

               (i) adding the following new definitions in proper alphabetical
     order:

          "Cash Management Obligations": as defined in the Guarantee and
     Collateral Agreement.

          "Cash Pooling Agreement": an agreement, substantially in the form of
     the Cash Pooling Agreement draft dated July 21, 2005 ("Draft Pooling
     Agreement") by and among Borrower and/or any of its Subsidiaries, on the
     one hand, and one or more banks or similar financing institutions, on the
     other hand, together with any documents evidencing or governing any
     obligations relating thereto (including any guarantee agreements and
     security documents contemplated by or customary in connection with the
     Draft Pooling Agreement), in each case as such agreements may be amended
     (including any

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     amendment and restatement thereof), supplemented or otherwise modified from
     time to time, including any agreement extending the maturity of,
     refinancing, replacing or otherwise restructuring obligations (or adding
     Foreign Subsidiaries as additional parties or other Subsidiaries as
     guarantors thereunder) under such agreement or any successor or replacement
     agreement and whether by the same or any other lender or group of lenders,
     provided that the terms of any such amendment, restatement, supplement or
     modification, extension, refinancing, replacement or other agreement are
     similar in all material respects to those in the Draft Pooling Agreement.
     The Cash Pooling Agreement provides a cash management system for Foreign
     Subsidiaries of the Borrower, and obligations of Foreign Subsidiaries
     thereunder may be guaranteed by the Borrower and its Domestic Subsidiaries,
     provided, however, that neither the Borrower nor any of its Domestic
     Subsidiaries may grant a security interest in the Collateral or their other
     assets for the purpose of such guarantee except to the extent the secured
     party is a Lender (or any Affiliate of a Lender).

          "Fourth Amendment": the Fourth Amendment dated as of October 7, 2005
     to this Agreement.

          "Fourth Amendment Effective Date": the date on which the conditions
     set forth in Section 4 of the Fourth Amendment shall have been satisfied,
     which date is October 20, 2005.

               (ii) in the definition of "Obligations", adding (A) the phrase
     "Cash Management Obligations," after the phrase "the Letters of Credit,"
     and (B) the phrase "or Cash Management Obligations" after the phrase "(or,
     in the case of the Hedge Agreements".

             (b) Section 2.6(c) of the Credit Agreement is amended by (i)
deleting the amount "$80,000,000" and substituting therefor the phrase
"$50,000,000 after the Fourth Amendment Effective Date", (ii) deleting the
amount "$300,000,000" and substituting therefor the amount "$350,000,000", (iii)
adding after the phrase "shall accept" which appears in the third sentence the
phrase "and shall be deemed to have accepted" and (iv) adding after the phrase
"shall make" which appears in the third sentence the phrase "and shall be deemed
to have made".

             (c) Section 2.13 of the Credit Agreement is amended by deleting
paragraph (f).

             (d) Section 7.2 of the Credit Agreement is amended by (i) deleting
the word "and" from the end of clause (k), (ii) deleting the period from the end
of clause (l) and substituting therefor the phrase "; and" and (iii) adding the
following at the end thereof:

             (m) Indebtedness in respect of Cash Management Obligations,
          including the Cash Pooling Agreement, or guarantees thereof, including
          the guarantee set forth in Section 2.1(f) of the Guarantee and
          Collateral Agreement.

             (e) Section 7.3 of the Credit Agreement is amended by deleting from
paragraph (p) the phrase "7.2(k)" and substituting therefor the phrase "7.2(l)".

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             (f) Section 7.3 of the Credit Agreement is amended by (i) deleting
the word "and" from the end of clause (o), (ii) deleting the period from the end
of clause (p) and substituting therefor the phrase "; and " and (iii) adding the
following at the end thereof:

             (q) Liens on cash, cash equivalents, deposit accounts and similar
          items of Foreign Subsidiaries securing Cash Management Obligations,
          including obligations in respect of any Cash Pooling Agreement, and
          guarantees by the Borrower or any of its Subsidiaries of such Cash
          Management Obligations or other Obligations (it being understood that
          the Borrower and the Domestic Subsidiaries may not provide a security
          interest in the Collateral or their other assets for Cash Management
          Obligations or obligations under any Cash Pooling Agreement to benefit
          Foreign Subsidiaries except to the extent the secured party is a
          Lender (or any Affiliate of a Lender)).

             (g) Section 7.9 of the Credit Agreement is amended by deleting the
last sentence and substituting therefor the following:

          Notwithstanding the foregoing, as long as no Default or Event of
          Default has occurred and is continuing the Borrower may purchase and
          cancel or redeem its Senior Subordinated Notes from the Net Cash
          Proceeds of Permitted Refinancing Indebtedness or from the Net Cash
          Proceeds of shares of common stock of the Borrower, in each case
          issued within 180 days prior to such purchase and cancellation or
          redemption.

             (h) Section 7.15 of the Credit Agreement is amended by deleting the
phrase "substantially concurrently therewith" from the last sentence and
substituting therefor, "in each case within 180 days prior to such purchase and
cancellation or redemption".

          3. Representations and Warranties. The Borrower hereby confirms that
the representations and warranties set forth in Section 4 of the Credit
Agreement, as amended by this Amendment, are true and correct in all material
respects as if made as of the Fourth Amendment Effective Date (except such
representations and warranties as are made as of a particular date, which such
representations and warranties shall be true and correct in all material
respects as if made as of such date). The Borrower represents and warrants that,
after giving effect to this Amendment, no Default or Event of Default has
occurred and is continuing.

          4. Effectiveness. This Amendment shall become effective as of the date
the conditions below are satisfied (the "Fourth Amendment Effective Date"):

             (a) Amendment. The Administrative Agent shall have received this
Amendment executed and delivered by the Administrative Agent, the Borrower and
the Required Lenders (or, in the case of any Lender, a lender addendum or
joinder agreement in a form specified by the Administrative Agent).

             (b) Amendment of the Guarantee and Collateral Agreement. The
Administrative Agent shall have received the First Amendment to the Guarantee
and Collateral Agreement, executed and delivered by an authorized officer of the
Borrower and each other

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Loan Party. The Lenders authorize the Administrative Agent to execute and
deliver such First Amendment.

          5. Continuing Effect of the Credit Agreement. This Amendment shall not
constitute an amendment or waiver of any provision of the Credit Agreement not
expressly referred to herein and shall not be construed as a waiver or consent
to any further or future action on the part of the Borrower that would require a
waiver or consent of the Lenders, the Administrative Agent or the Other Agents.
Except as expressly amended hereby, the provisions of the Credit Agreement are
and shall remain in full force and effect.

          6. Counterparts. This Amendment may be executed by the parties hereto
in any number of separate counterparts (including telecopied counterparts), each
of which shall be deemed to be an original, and all of which taken together
shall be deemed to constitute one and the same instrument.

          7. GOVERNING LAW. THIS AMENDMENT SHALL BE GOVERNED BY, AND CONSTRUED
AND INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

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          IN WITNESS WHEREOF, the parties hereto have caused this Amendment to
be duly executed and delivered by their respective proper and duly authorized
officers as of the day and year first above written.

                                        TENNECO AUTOMOTIVE INC.



                                        By:  /s/ John E. Kunz
                                           ---------------------------------
                                           Name: John E. Kunz
                                           Title: Vice President and Treasurer



                                        JPMORGAN CHASE BANK, N.A., as
                                        Administrative Agent and as a Lender



                                        By:  /s/ Richard W. Duker
                                           ---------------------------------
                                           Name: Richard W. Duker
                                           Title: Managing Director