8-A12B/A

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                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

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                                   FORM 8-A/A

                         Post-Effective Amendment No.1

               FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES
                   PURSUANT TO SECTION 12(b) OR 12(g) OF THE
                        SECURITIES EXCHANGE ACT OF 1934

                            TENNECO AUTOMOTIVE INC.
             (Exact Name of Registrant as Specified in its Charter)

              DELAWARE                                     76-0515284
       (State of Incorporation                           (IRS Employer
           or Organization)                           Identification Number)

        500 North Field Drive
        Lake Forest, Illinois                                 60045
        (Address of Principal                               (Zip Code)
         Executive Offices)

     If this form relates to the registration of a class of securities pursuant
to Section 12(b) of the Exchange Act and is effective pursuant to General
Instruction A. (c), check the following box [X]

     If this form relates tot he registration of a class of securities pursuant
to Section 12(g) of the Exchange Act and is effective pursuant to General
Instruction A.(d), check the following box [ ]

SECURITIES TO BE REGISTERED PURSUANT TO SECTION 12(B) OF THE ACT:

         TITLE OF EACH CLASS                  NAME OF EACH EXCHANGE ON WHICH
           TO BE REGISTERED                   EACH CLASS IS TO BE REGISTERED
           ----------------                   ------------------------------
  RIGHTS TO PURCHASE SERIES B JUNIOR         THE NEW YORK STOCK EXCHANGE, INC.
    PARTICIPATING PREFERRED STOCK            THE CHICAGO STOCK EXCHANGE
                                             THE LONDON STOCK EXCHANGE
                                             THE PACIFIC EXCHANGE, INC.


SECURITIES TO BE REGISTERED PURSUANT TO SECTION 12(g) OF THE ACT: NONE.

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     Tenneco Automotive Inc., a Delaware corporation formerly known as Tenneco
Inc. (the "Registrant" or "Tenneco"), hereby amends Items 1 and 2 of its
Registration Statement on Form 8-A filed on September 17, 1998.  The complete
text of each item, as amended, is set forth below.

Item 1. DESCRIPTION OF REGISTRANT'S SECURITIES TO BE REGISTERED

     On September 9, 1998, the Board of Directors of the Registrant declared a
dividend of one preferred share purchase right (a "Right") for each outstanding
share of common stock, par value $.01 per share, of the Registrant (the "Common
Stock").  The dividend was payable on September 21, 1998 (the "Record Date") to
the stockholders of record on that date.  Each Right entitles the registered
holder to purchase from the Registrant one one-thousandth of a share of Series
B Junior Participating Preferred Stock, par value $.01 per share, of the
Registrant (the "Preferred Stock") at a price of $130.00 per one one-thousandth
of a share of Preferred Stock (the "Purchase Price"), subject to adjustment.
The description and terms of the Rights are set forth in a Qualified Offer Plan
Rights Agreement dated as of September 9, 1998, as the same may be amended from
time to time (the "Rights Agreement"), between the Registrant and First Chicago
Trust Company of New York, as Rights Agent.  The Rights will expire on
September 9, 2008 (the "Final Expiration Date"), unless the Final Expiration
Date is advanced or extended or unless the Rights are earlier redeemed or
exchanged by the Registrant, in either case as described below.

     Effective as of 7:58 a.m., eastern standard time, on November 5, 1999, the
Registrant effected a 1-for-5 reverse stock split, whereby each five issued
shares of Common Stock as of 7:58 a.m., eastern standard time, on November 5,
1999 were reclassified into one share of Common Stock, with fractional shares
settled in cash.  Section 11(n) of the Rights Agreement provides that in the
event of any subdivision of shares of Common Stock into a greater or lesser
number of shares, then, in each such case, the number of Rights associated with
each share of Common Stock then outstanding, or issued or delivered thereafter,
shall be proportionately adjusted so that the number of Rights thereafter
associated with each share of Common Stock following any such event shall equal
the result obtained by multiplying the number of Rights associated with each
share of Common Stock immediately prior to such event by a fraction the
numerator of which shall be the total number of shares of Common Stock
outstanding immediately prior to the occurrence of the event and the
denominator of which shall be the total number of shares of Common Stock
outstanding immediately following the occurrence of such event.  Accordingly,
the Registrant adjusted the number of Rights associated with each share of
Common Stock from one Right to five Rights in connection with the reverse stock
split.

     In connection with the adoption of the Rights Agreement, the Board of
Directors also adopted a "TIDE" (Three-year Independent Director Evaluation)
mechanism.  Under the TIDE mechanism, an independent Board committee will
review, on an ongoing basis, the Rights Agreement and developments in rights
plans generally, and, if it deems appropriate, recommend modification or
termination of the Rights Agreement.  This independent committee will report to
Tenneco's Board at least every three years as to whether the Rights Agreement
continues to be in the best interests of Tenneco's stockholders.

     The Rights are not exercisable until the "Distribution Date." Under the
Rights Agreement, a "Distribution Date" occurs upon the earlier of (i) 10 days
following a public announcement that a person or group of affiliated or
associated persons has become an "Acquiring Person" or (ii) 10 business days
(or such later date as may be determined by action of the Board of Directors
prior to such time as any person or group of affiliated or associated persons
becomes an Acquiring Person) following the commencement of, or announcement of
an intention to make, a tender offer or exchange offer the consummation of
which would result in the beneficial ownership by a person or group of 20% or
more of the outstanding shares of Common Stock.  Except in certain situations,
a person or group of affiliated or associated persons becomes an "Acquiring
Person" upon acquiring beneficial ownership of 20% or more of the outstanding
shares of Common Stock.  Until the Distribution Date, the Rights will be
evidenced, with respect to any of the Common Stock certificates outstanding as
of the Record Date, by such Common Stock certificate.

     The Rights will not become exercisable in connection with a "Qualified
Offer," which is an all-cash tender offer for all outstanding Common Stock that
is fully financed, remains open for a period of at least 60 business days,
results in the offeror owning at least 85% of the Common Stock after
consummation of the offer, assures a prompt second-step acquisition of shares
not purchased in the initial offer at the same price as the initial offer and
meets certain other requirements.

     The Rights Agreement provides that, until the Distribution Date (or
earlier expiration of the Rights), the Rights will be transferred with and only
with the Common Stock.  Until the Distribution Date (or earlier expiration of
the Rights), new Common Stock certificates issued after the Record Date upon
transfer or new issuances of Common Stock will contain a notation incorporating
the Rights Agreement by reference.  Until the Distribution Date (or earlier
expiration of the Rights), the surrender for transfer of any certificates for
shares of Common Stock outstanding as of the Record Date, even without such
notation or a copy of this Summary of Rights, will also constitute the transfer
of the Rights associated with the shares of Common Stock represented by such
certificate.  As soon as practicable following the Distribution Date, separate
certificates evidencing the Rights ("Right Certificates") will be mailed to
holders of record of the Common Stock as of the close of business on the
Distribution Date and such separate Right Certificates alone will evidence the
Rights.

     The Purchase Price payable, and the number of shares of Preferred Stock
or other securities or property issuable, upon exercise of the Rights is
subject to adjustment from time to time to prevent dilution (i) in the event of
a stock dividend on, or a subdivision, combination or reclassification of, the
Preferred Stock, (ii) upon the grant to holders of the Preferred Stock of
certain rights or warrants to subscribe for or purchase Preferred
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Stock at a price, or securities convertible into Preferred Stock with a
conversion price, less than the then-current market price of the Preferred Stock
or (iii) upon the distribution to holders of the Preferred Stock of evidences
of indebtedness or assets (excluding regular periodic cash dividends or
dividends payable in Preferred Stock) or of subscription rights or warrants
(other than those referred to above).

     The number of outstanding Rights is subject to adjustment in the event of
a stock dividend on the Common Stock payable in shares of Common Stock or
subdivisions, consolidations or combinations of the Common Stock occurring, in
any such case, prior to the Distribution Date.

     Shares of Preferred Stock purchasable upon exercise of the Rights will not
be redeemable. Each share of Preferred Stock will be entitled, when, as and if
declared, to a minimum preferential quarterly dividend payment of $25.00 per
share but will be entitled to an aggregate dividend of 200 times the dividend
declared per share of Common Stock. In the event of liquidation, dissolution or
winding up of the Registrant, the holders of the Preferred Stock will be
entitled to a minimum preferential payment of $500.00 per share (plus any
accrued but unpaid dividends) but will be entitled to an aggregate payment of
200 times the payment made per share of Common Stock. Each share of Preferred
Stock will have 200 votes, voting together with the Common Stock. Finally, in
the event of any merger, consolidation or other transaction in which
outstanding shares of Common Stock are converted or exchanged, each share of
Preferred Stock will be entitled to receive 200 times the amount received per
share of Common Stock. These rights are protected by customary antidilution
provisions.

     In the event that any person or group of affiliated or associated persons
becomes an Acquiring Person, each holder of a Right, other than Rights
beneficially owned by the Acquiring Person (which will thereupon become void),
will thereafter have the right to receive upon exercise of a Right that number
of shares of Common Stock having a market value of two times the exercise price
of the Right.

     In the event that, after a person or group has become an Acquiring Person,
the Registrant is acquired in a merger or other business combination
transaction or 50% or more of its consolidated assets or earning power are
sold, proper provisions will be made so that each holder of a Right (other than
Rights beneficially owned by an Acquiring Person which will have become void)
will thereafter have the right to receive upon the exercise of a Right that
number of shares of common stock of the person with whom the Registrant has
engaged in the foregoing transaction (or its parent) that at the time of such
transaction have a market value of two times the exercise price of the Right.

     At any time after any person or group becomes an Acquiring Person and prior
to the earlier of one of the events described in the previous paragraph or the
acquisition by such Acquiring Person of 50% or more of the outstanding shares of
Common Stock, the Board of Directors of the Registrant may exchange the Rights
(other than Rights owned by such Acquiring Person which will have become void),
in whole or in part, for shares of Common Stock or Preferred Stock (or a series
of the Registrant's preferred stock having equivalent rights, preferences and
privileges), at an exchange ratio of one-fifth of one share of Common Stock, or
a fractional share of Preferred Stock (or other preferred stock) equivalent in
value thereto, per Right.

     With certain exceptions, no adjustment in the Purchase Price will be
required until cumulative adjustments require an adjustment of at least 1% in
such Purchase Price. No fractional shares of Preferred Stock or Common Stock
will be issued (other than fractions of Preferred Stock which are integral
multiples of one one-thousandth of a share of Preferred Stock, which may, at
the election of the Registrant, be evidenced by depositary receipts), and in
lieu thereof an adjustment in cash will be made based on the current market
price of the Preferred  Stock or the Common Stock.

     At any time prior to the time an Acquiring Person becomes such, the Board
of Directors of the Registrant may redeem the Rights in whole, but not in part,
at a price of $.01 per Right (the "Redemption Price") payable, at the option of
the Registrant, in cash, shares of Common Stock or such other form of
consideration as the Board of Directors of the Registrant shall determine. The
redemption of the Rights may be made
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effective at such time, on such basis and with such conditions as the Board of
Directors in its sole discretion may establish. Immediately upon any redemption
of the Rights, the right to exercise the Rights will terminate and the only
right of the holders of Rights will be to receive the Redemption Price.

     For so long as the Rights are then redeemable, the Registrant may, except
with respect to the Redemption Price, amend the Rights Agreement in any manner.
After the Rights are no longer redeemable, the Registrant may, except with
respect to the Redemption Price, amend the Rights Agreement in any manner that
does not adversely affect the interests of holders of the Rights.

     Until a Right is exercised or exchanged, the holder thereof, as such, will
have no rights as a shareowner of the Registrant, including, without limitation,
the right to vote or to receive dividends.

     As of January 31, 2000, three were 33,674,559 shares of Common Stock
outstanding, with each share carrying five Rights. Until the Distribution Date,
the Registrant will issue five Rights with each share of Common Stock that shall
become outstanding so that all such shares will have attached rights. Two
million shares of Preferred Stock have been reserved for issuance upon exercise
of the Rights.

     The Rights have certain anti-takeover effects. The Rights will cause
substantial dilution to any person or group that attempts to acquire the
Registrant, other than pursuant to a Qualified Offer, without the approval of
the Registrant's Board of Directors. The Rights should not interfere with any
merger or other business combination approved by the Board of Directors of the
Registrant since the Board of Directors may, at its option, at any time until an
Acquiring Person becomes such, redeem all, but not less than all, of the then
outstanding Rights at the applicable redemption price.

     This summary description of the Rights does not purport to be complete and
is qualified in its entirety by reference to the Rights Agreement (which
includes as Exhibit B the Form of Rights Certificate), as the same may be
amended from time to time, a copy of which is incorporated herein by reference
to Exhibit 4.1 to this registration statement. Copies of the Rights Agreement
will be available free of charge from the Registrant.


ITEM 2. EXHIBITS

     The following documents are filed as exhibits to this registration
statement.

     *4.1  Qualified Offer Plan Rights Agreement, dated as of September 9, 1998,
           between the Registrant and First Chicago Trust Company of New York,
           as Rights Agent, which includes as Exhibit B thereto the Form of
           Right Certificate.

      4.2  Certificate of Adjustment dated December, 1999.

* Previously filed.
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                                   SIGNATURE

     Pursuant to the requirements of Section 12 of the Securities Exchange Act
of 1934, the Registrant has duly caused this registration statement to be signed
on its behalf by the undersigned, thereto duly authorized.

March 8, 2000                               TENNECO AUTOMOTIVE INC.

                                            By: /s/ Timothy R. Donovan
                                               ---------------------------------
                                                Timothy R. Donovan
                                                Senior Vice President and
                                                General Counsel

EX-4.2

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                                                                     EXHIBIT 4.2


                           CERTIFICATE OF ADJUSTMENT
                                       OF
                  TENNECO AUTOMOTIVE INC. (F/K/A TENNECO INC.)


To:  First Chicago Trust Company of New York
     P.O. Box 2500
     Jersey City, New Jersey 07303-2500
     Attention: Chairman and Chief Executive Officer

     Each Transfer Agent for the Common
      Stock of Tenneco Automotive Inc. (f/k/a Tenneco Inc.)

     TENNECO AUTOMOTIVE INC. (F/K/A TENNECO INC.), a corporation organized and
existing under the laws of the State of Delaware (the "Company"), does hereby
certify as follows:

          1.   The Company is a party to the Rights Agreement (the
"Agreement"), dated as of September 9, 1998, between the Company and First
Chicago Trust Company of New York, as Rights Agent (the "Rights Agent").

          2.   Effective as of 7:58 a.m., eastern standard time, on November 5,
1999, the Company effected a 1 for 5 reverse stock split, whereby each five
issued shares of Common Stock of the Company (the "Common Stock") as of 7:58
a.m., eastern standard time, on November 5, 1999 were reclassified into one
share of Common Stock, with fractional shares settled in cash (the
"Reclassification").

          3.   Section 11(n) of the Agreement provides that in the event of any
subdivision of shares of Common Stock into a greater or lesser number of
shares, then, in each such case, the number of Rights (as defined in the
"Agreement") associated with each share of Common Stock then outstanding, or
issued or delivered thereafter, shall be proportionately adjusted so that the
number of Rights thereafter associated with each share of Common Stock
following any such event shall equal the result obtained by multiplying the
number of Rights associated with each share of Common Stock immediately prior
to such event by a fraction the numerator of which shall be the total number of
shares of Common Stock outstanding immediately prior to the occurrence of the
event and the denominator of which shall be the total number of shares of
Common Stock outstanding immediately following the occurrence of such event.

     4.   Whenever an adjustment is made as provided in Section 11 of the
Agreement, the Company must, pursuant to Section 12 of the Agreement, (a)
prepare a certificate setting forth the adjustment and a brief summary of the
facts accounting therefor and (b) file a copy of such certificate with the
Rights Agent and each transfer agent for the Common Stock.

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     5.   Pursuant to Section 12 of the Agreement, notification is hereby given
that the number of Rights associated with each share of Common Stock has been
adjusted from one (1) Right to five (5) Rights.

     IN WITNESS WHEREOF, the undersigned has executed this Certificate of
Adjustment this ___ day of December, 1999.


                                   TENNECO AUTOMOTIVE INC. (f/k/a Tenneco Inc.)



                                   By: /s/ Timothy R. Donovan
                                       -----------------------------------------
                                   Name: Timothy R. Donovan
                                   Office: SVP and General Counsel