Document:

<PAGE>   1
                                                                   EXHIBIT 10.62

                         SECOND SUPPLEMENT TO PRODUCTION
                               PAYMENT CONVEYANCE

         THIS SECOND SUPPLEMENT TO PRODUCTION PAYMENT CONVEYANCE (this
"Supplement"), dated as of the date set out at the end hereof, is made by
TransTexas Gas Corporation, a Delaware corporation ("Grantor"), Southern
Producer Services, L.P. ("SPS"), TCW Portfolio No. 1555 DR V Sub-Custody
Partnership, L.P. ("Fund V"), and TCW DR VI Investment Partnership, L.P. ("Fund
VI"). SPS, Fund V and Fund VI are herein collectively called "Grantee".

                                    RECITALS:

A.       Effective as of March 1, 2000, Grantor executed in favor of Grantee
         that certain Production Payment Conveyance dated as of March 14, 2000
         (as heretofore amended, the "Original Conveyance"), which Original
         Conveyance (including previous supplements thereto) has been recorded
         as set forth in Schedule 1 hereto.

B.       Pursuant to the First Supplement to Production Payment Conveyance
         listed on Schedule 1 hereto, Grantee and Grantor added the amount of
         $8,000,000 to the unliquidated balance of the Primary Sum under the
         Original Conveyance. Grantee and Grantor now desire to further
         supplement and amend the Original Conveyance in order make additional
         properties subject thereto and to account for the payment by SPS of
         additional funds to Grantor.

C.       As described in Section 8.7 of the Original Conveyance, and pursuant to
         the Purchase Agreement referred to in the Original Conveyance, Fund V
         and Fund VI have appointed TCW Asset Management Company to act as their
         agent in connection with supplements and amendments to the Original
         Conveyance.

                           SUPPLEMENTS AND AGREEMENTS:

         FOR A GOOD AND VALUABLE CONSIDERATION, the receipt and sufficiency of
which are hereby acknowledged, Grantor and Grantee do hereby agree, act and
covenant as follows:

         1. All capitalized terms used but not defined herein shall have the
meanings assigned to them in the Original Conveyance.

         2. Effective as of 9:00 a.m. Houston, Texas time, on September 8, 2000
(the "Effective Time"), the Original Conveyance is amended in order to add the
amount of Ten Million Dollars ($10,000,000) to the unliquidated balance of the
Primary Sum, as such unliquidated balance stood as of the Effective Time after
giving effect to all applications of PP Proceeds made before the Effective Time.
After giving effect to such amendment (and to such application of PP Proceeds),
the unliquidated balance of the Primary Sum as of the Effective Time is
$32,446,634. (Any PP Proceeds received after the Effective Time on September 8,
2000 shall be deemed to have been received on the next following Business Day.)

                                        1

<PAGE>   2

         3. Exhibit A to the Original Conveyance is hereby amended and
supplemented, effective as of the Effective Time, to include at the end thereof
Exhibit A hereto (herein called "Additional Exhibit A").

         4. The terms "NRI Percentage," "PP Hydrocarbons," "Subject
Hydrocarbons," "Subject Interests," "Subject Lands," and "Subject Wells," as
such terms are defined and used in the Original Conveyance, are hereby amended,
effective as of the Effective Time, in order to take into account and recognize
the addition of Additional Exhibit A hereto to the end of Exhibit A as attached
to the Original Conveyance, and all other direct or indirect references in the
Original Conveyance shall likewise be considered amended in order to take into
account and recognize such amendment and the addition of Additional Exhibit A
hereto to the end of Exhibit A as attached to the Original Conveyance.

         5. For the above-recited consideration, Grantor does hereby, in order
to more fully effectuate the amendments and other provisions herein contained,
GRANT, BARGAIN, SELL, CONVEY, ASSIGN, TRANSFER, SET OVER and DELIVER unto
Grantee, as a production payment, to be held in undivided interests in
proportion to their Percentage Shares, a term overriding royalty interest carved
out of and burdening the Subject Interests (including the "Additional Subject
Interests," as defined below) equal to and measured by all "Additional PP
Hydrocarbons," as defined below, in, under and that may be produced from (or, to
the extent pooled or unitized, allocated to) the Subject Lands (including the
"Additional Subject Lands," as defined below), with such production payment to
be effective as to deliveries of Additional PP Hydrocarbons as of the Effective
Time, and to terminate as of the Termination Time.

         TO HAVE AND TO HOLD the above-described production payment, upon and
subject to the terms of the Original Conveyance, as amended hereby, unto
Grantee, and its successors and Permitted Assigns, until the Termination Time.

         As used herein, the following terms have the following meanings:

         (a)      "Additional PP Hydrocarbons" means the Dedication Percentage
                  of the NRI Percentage (as the definitions of such terms are
                  amended herein) of:

                  (i)      all Hydrocarbons in, under or that may be produced
                           from (or, to the extent pooled or unitized, allocated
                           to) any Additional Subject Lands prior to the
                           Termination Time (as determined after giving effect
                           to this Supplement), and

                  (ii)     all other Hydrocarbons in, under or that may be
                           produced from (or, to the extent pooled or unitized,
                           allocated to) the Subject Lands prior to the
                           Termination Time, as determined after giving effect
                           to this Supplement and the instrument listed as item
                           2 on Schedule 1 hereto (this Supplement and such
                           other instruments being herein collectively called
                           the "Supplements"), to the extent such Hydrocarbons
                           are included within the PP Hydrocarbons as a result
                           of the Termination Time being changed because of the
                           Supplements.

                                        2

<PAGE>   3

         (b)      "Additional Subject Interests" means:

                  (i)      All of the leasehold interests and other property
                           interests described in Additional Exhibit A; and

                  (ii)     Without limitation of the foregoing, all other right,
                           title and interest (of whatever kind or character,
                           whether legal or equitable and whether vested or
                           contingent) of Grantor in and to the oil, gas and
                           other minerals in and under or that may be produced
                           from the Additional Subject Lands (including
                           interests in oil, gas or mineral leases to the extent
                           the same cover such lands, overriding royalties,
                           production payments and net profits interests in such
                           lands or such leases, and fee mineral interests, fee
                           royalty interests and other interests in such oil,
                           gas and other minerals) even though Grantor's
                           interest in such oil, gas and other minerals may be
                           incorrectly described in, or omitted from, Additional
                           Exhibit A; and

                  (iii)    All rights, titles and interests of Grantor in and
                           to, or otherwise derived from, all presently existing
                           and valid oil, gas or mineral unitization, pooling,
                           or communitization agreements, declarations or orders
                           and in and to the properties covered and the units
                           created thereby (including all units formed under
                           orders, rules, regulations, or other official acts of
                           any federal, state, or other authority having
                           jurisdiction, voluntary unitization agreements,
                           designations or declarations, and so-called "working
                           interest units" created under operating agreements or
                           otherwise) relating to the properties described in
                           subsections (i) or (ii) above in this definition.

         (c)      "Additional Subject Lands" means the lands and depths
                  described in Additional Exhibit A hereto (where no depth limit
                  is specified, Additional Subject Lands shall include all
                  depths).

         Without limitation of the generality of the provisions of Section 4,
above, or of the foregoing provisions of this Section 5, effective as to
deliveries of Additional PP Hydrocarbons at and after the Effective Time, the
definition of PP Hydrocarbons as found in the Original Conveyance is hereby
amended to include all Additional PP Hydrocarbons, as defined herein, the
definition of Subject Lands as found in the Original Conveyance shall be amended
to include all Additional Subject Lands, as defined herein, and the definition
of Subject Interests as found in the Original Conveyance shall be amended to
include all Additional Subject Interests, as defined herein; the term "Initial
Time", as found in the definition of "Subject Hydrocarbons" in the Original
Conveyance, shall be deemed to refer to the Effective Time, as such term is
defined herein, but only as to Additional PP Hydrocarbons, and the Original
Conveyance is amended to so provide.

         6. All of the terms and provisions of the Original Conveyance, as the
same is amended and supplemented hereby, are ratified, adopted, affirmed and
renewed, and remain in full force and effect for the benefit of Grantee, the
Beneficiaries, Funds Agent, and their respective successors and assigns. To the
extent, if any, required to give effect to the Supplements or to the

                                        3

<PAGE>   4

ratification, adoption, affirmation and renewal provided for in the preceding
sentence, Grantor does hereby GRANT, BARGAIN, SELL, CONVEY, ASSIGN, TRANSFER,
SET OVER AND DELIVER unto Grantee, as a production payment, to be held in
undivided interests in proportion to their Percentage Shares, a term overriding
royalty interest carved out of and burdening the Subject Interests equal to and
measured by all PP Hydrocarbons in and under and that may be produced from (or,
to the extent pooled or unitized, allocated to) the Subject Lands, with such
production payment to terminate as of the Termination Time and to be held upon
and subject to the terms of the Original Conveyance as amended hereby.

         7. The definition of "Percentage Share" in Section 1.1 of the Original
Conveyance is hereby amended in its entirety to read as follows:

                  " 'Percentage Share' means, with respect to each Person
         included in Grantee, the fractional undivided interest which it owns in
         the Production Payment at the time in question. From the initial grant
         of the Production Payment until 9:00 a.m. Houston, Texas time, on June
         7, 2000, the Percentage Share of each Person included in Grantee was
         as follows:

                  Fund V            42.859594%
                  Fund VI           21.429797%
                  SPS               35.710609%

         From and after 9:00 a.m. Houston, Texas time, on June 7, 2000, until
         9:00 a.m. Houston, Texas time, on September 8, 2000, the Percentage
         Share of each Person included in Grantee was as follows:

                  Fund V            33.048697%
                  Fund VI           16.524349 %
                  SPS               50.426954%

         From and after 9:00 a.m. Houston, Texas time, on September 8, 2000, the
         Percentage Share of each Person included in Grantee is as follows:

                  Fund V            22.863142%
                  Fund VI           11.431571%
                  SPS               65.705287% "

The foregoing Percentage Shares of Fund V, Fund VI and SPS, respectively, are in
this Amendment called their "amended Percentage Shares".

         In consideration of the additional purchase price payment made by SPS
to Grantor and the foregoing increase in the unliquidated balance of the Primary
Sum:

                  (a) Fund V and Fund VI do hereby GRANT, BARGAIN, SELL, CONVEY,
         ASSIGN, TRANSFER, SET OVER and DELIVER unto SPS such additional
         undivided interests in the Production Payment as are necessary in order
         to cause SPS, Fund V and

                                        4

<PAGE>   5

         Fund VI to own the Production Payment, at and after the Effective Time,
         in undivided interests in proportion to their respective amended
         Percentage Shares, and

                  (b) Fund V and Fund VI do further assign unto SPS such
         undivided interests in Fund V's and Fund VI's accounts receivable from
         the sale of PP Hydrocarbons - to the extent such accounts receivable
         exist and are unpaid at the Effective Time and arise from the sale of
         PP Hydrocarbons before the Effective Time - as are necessary in order
         to cause SPS, Fund V and Fund VI to share in all collections of such
         accounts receivable after the Effective Time in proportion to their
         respective amended Percentage Shares.

         TO HAVE AND TO HOLD the same, upon and subject to the terms of the
Original Conveyance, as amended hereby, unto SPS and its successors and
Permitted Assigns, until the Termination Time.

         8. This Supplement may be executed in multiple counterparts, all of
which are identical.

         9. This Supplement shall be binding upon and shall inure to the benefit
of the parties hereto, and their respective successors and assigns, and all of
the covenants and agreements contained in the Original Conveyance, as amended
hereby, shall be deemed to be covenants and agreements running with the lands
affected thereby.

         10. This Supplement shall be governed by and construed in accordance
with the laws of the State of Texas, without regard to principles of conflicts
of laws.

         IN WITNESS WHEREOF, this Supplement is executed by the parties hereto
on the dates set out below in their respective acknowledgments, but effective as
of the Effective Time.

                                           TRANSTEXAS GAS CORPORATION

                                           By: /s/ ED DONAHUE
                                              ----------------------------------
                                                    Ed Donahue
                                                    Vice President

Grantor's address:                         1300 North Sam Houston Parkway East
                                           Suite 310
                                           Houston, Texas 77032-2949
                                           Attention: Ed Donahue, Vice President
                                           Telephone: 281/987-8600
                                           Telecopy:  281/986-8865

                                        5

<PAGE>   6

                                         SOUTHERN PRODUCER SERVICES, L.P.

                                         By:      SC Ashwood Holdings, Inc.,
                                                  its general partner

                                                  By: /s/ DAVID W. STEWART
                                                     ---------------------------
                                                           David W. Stewart
                                                           Vice President

SPS's address:                           1200 Smith Street
                                         Suite 2890
                                         Houston, Texas 77002
                                         Attention: David W. Stewart
                                         Telephone: 713/276-1902
                                         Telecopy:  713/276-1990

                                         TCW PORTFOLIO NO. 1555 DR V SUB-CUSTODY
                                         PARTNERSHIP, L.P., and
                                         TCW DR VI INVESTMENT PARTNERSHIP, L.P.

                                         By:      TCW ASSET MANAGEMENT COMPANY,
                                                  as Agent

                                                  By: /s/ KURT A. TALBOT
                                                     ---------------------------
                                                         Kurt A. Talbot
                                                         Senior Vice President

Fund V's and Fund VI's address:          c/o Trust Company of the West
                                         865 South Figueroa
                                         Los Angeles, California  90017
                                         Attention: Thomas F. Mehlberg
                                         Telephone: 213/244-0702
                                         Telecopy:  213/244-0604

This document prepared by:

John W. Rain
Thompson & Knight L.L.P.
1700 Pacific Avenue, Suite 3300
Dallas, Texas  75201

                                        6

<PAGE>   7

STATE OF TEXAS           )
                         )
COUNTY OF HARRIS         )

        The foregoing instrument was acknowledged before me on this 11th day of
September, 2000, by Ed Donahue, the Vice President of TransTexas Gas
Corporation, a Delaware corporation, on behalf of such corporation.

                                           /s/ NANCY L. JAMES
                                        ---------------------------------------
        [SEAL]                          Notary Public, State of Texas

STATE OF TEXAS           )
                         )
COUNTY OF HARRIS         )

         The foregoing instrument was acknowledged before me on this 11th day
of September, 2000, by David W. Stewart, the Vice President of SC Ashwood
Holdings, Inc., a Georgia corporation, on behalf of such corporation acting as
general partner of Southern Producer Services L.P., a Delaware limited
partnership, and on behalf of such limited partnership.

                                           /s/ NANCY L. JAMES
                                        ---------------------------------------
        [SEAL]                          Notary Public, State of Texas

STATE OF TEXAS           )
                         )
COUNTY OF HARRIS         )

         The foregoing instrument was acknowledged before me on this 11th day
of September, 2000, by Kurt A. Talbot, the Senior Vice President of TCW Asset
Management Company, a California corporation, on behalf of such corporation
acting as agent as aforesaid.

                                           /s/ NANCY L. JAMES
                                        ---------------------------------------
        [SEAL]                          Notary Public, State of Texas

                                        7

<PAGE>   8

                                                                      SCHEDULE 1

                               RECORDING SCHEDULE

1.       Production Payment Conveyance dated as of March 14, 2000, to TCW
         Portfolio No. 1555 DR V Sub-Custody Partnership, L.P., TCW DR VI
         Investment Partnership, L.P., Southern Producer Services, L.P. from
         TransTexas Gas Corporation.

<TABLE>
<CAPTION>
Recording Jurisdiction                  Recording Data
----------------------                  --------------

<S>                                     <C>
Chambers County, TX                     Document No. 00-448-604,
                                        Filed 3/17/2000

Galveston County, TX                    Film Code #014-39-1028,
                                        Filed 3/17/2000

Jim Hogg County, TX                     Volume 17, Page 362,
                                        Filed 3/20/2000

Live Oak County, TX                     Volume 449, Page 135,
                                        Filed 3/20/2000

Wharton County, TX                      Volume 360, Page 596,
                                        Filed 3/17/2000

Zapata County, TX                       Volume 629, Page 471,
                                        Filed 3/17/2000

General Land Office of Texas            Sent for filing
</TABLE>

2.       First Supplement to Production Payment Conveyance among TransTexas Gas
         Corporation, Southern Producer Services, L.P., TCW Portfolio No. 1555
         DR V Sub- Custody Partnership, L.P. and TCW DR VI Investment
         Partnership, L.P.

<TABLE>
<CAPTION>
Recording Jurisdiction                  Recording Data
----------------------                  --------------

<S>                                     <C>
Chambers County, TX                     Document No. 00-459-630
                                        Filed 6/9/2000

Galveston County, TX                    Film Code 014-62-1617
                                        Filed 6/9/2000

Jim Hogg County, TX                     Volume 19, Page 526,
                                        Filed 6/9/2000

Live Oak County, TX                     Volume 450, Page 428,
                                        Filed 6/12/2000

Wharton County, TX                      Volume 371, Page 458,
                                        Filed 6/9/2000

Zapata County, TX                       Volume 634, Page 110,
                                        Filed 6/9/2000

General Land Office of Texas            sent for filing
</TABLE>

                                        1

<PAGE>   9

                                    EXHIBIT A

                          ADDITIONAL SUBJECT INTERESTS

American National Insurance Company Gas Unit No. 1
Calhoun County, Texas

         The entire (100.00%) interest in and to those certain oil, gas and
mineral leases described as follows:

         (a) Oil and Gas lease dated February 5, 1997, from American National
         Insurance Company, as lessor, to Adobe Energy, Inc., as lessee, a
         Memorandum of which is recorded in Volume 179, page 185 of the Official
         Records of Calhoun County, Texas; and

         (b) Oil and Gas lease dated October 6, 1997, from American National
         Insurance Company, as lessor, to Adobe Energy, Inc., as lessee, a
         Memorandum of which is recorded in Volume 191, page 482 of the Official
         Records of Calhoun County, Texas, as amended by that certain Correction
         of Description of Land in Oil and Gas Lease and Memorandum of Oil, Gas
         and Mineral Lease dated August 23, 1999, by and between American
         National Insurance Company and TransTexas Gas Corporation, recorded in
         Volume 236, page 622 of the Official Records of Calhoun County, Texas;

insofar as said leases cover and include 160.00 acres of land more particularly
described by metes and bounds on Exhibit "A", and being depicted on the map or
plat attached as Exhibit "B", to that certain Declaration of Unit dated January
4, 2000, by TransTexas Gas Corporation, recorded in Volume 245, page 46 of the
Official Records of Calhoun County, Texas.

<TABLE>
<S>                                                <C>
             Working Interest:                     1.0000000

             Net Revenue Interest:                  .7250000
</TABLE><PAGE>   1

                                                                   EXHIBIT 10.63

                             SUBORDINATION AGREEMENT

         This Subordination Agreement (this "Agreement") is made as of September
7, 2000, by Firstar Bank of Minnesota as Trustee under the Indenture referred to
below (in such capacity, herein called the "Mortgage Holder") and TransTexas Gas
Corporation, a Delaware corporation (herein called "TransTexas") for the benefit
of Southern Producer Services, L.P., TCW Portfolio No. 1555 DR V Sub-Custody
Partnership, L.P. and TCW DR VI Investment Partnership, L.P. (herein
collectively called the "Production Payment Owners").

                                    RECITALS:

         1. The Mortgage Holder and TransTexas have entered into that certain
Indenture dated as of March 15, 2000 (herein, as from time to time amended or
supplemented, called the "Indenture"), for the equal and ratable benefit of the
holders of TransTexas's Senior Secured Notes due 2005. Pursuant to the
Indenture, TransTexas has executed and delivered certain mortgages, deeds of
trust, security agreements and financing statements (collectively, the "Security
Documents") to secure such Notes. A true and complete list of such Security
Documents which burden properties in Texas is attached as Schedule 1 hereto and
made a part hereof. Each deed of trust and mortgage listed on Schedule 1 is
herein called a "Mortgage".

         2. As described in Section 9.2 of each Mortgage, TransTexas has
heretofore executed and delivered to the Production Payment Owners that certain
Production Payment Conveyance made effective as of 9:00 a.m., Houston, Texas
time on March 1, 2000 (defined in each such Section 9.2 as the "Production
Payment Conveyance" and herein called the "Original Conveyance"), pursuant to
which TransTexas conveyed and assigned to the Production Payment Owners a
certain production payment (defined in each such Section 9.2 as the "Production
Payment" and herein called the "Original Production Payment"). As described in
Section 9.2 of each Mortgage, the Original Conveyance was given pursuant to an
Order of the United States Bankruptcy Court. As contemplated in such Court
Order, the Original Conveyance has heretofore been supplemented by a First
Supplement to Production Payment Conveyance, dated as of June 7, 2000 (the
"First Supplement"), to increase the unliquidated balance of the "Primary Sum"
thereunder. The Original Conveyance and the First Supplement have been recorded
as set forth in Schedule 1 to Exhibit A hereto.

         3. Concurrently herewith, in consideration of funds to be paid to
TransTexas, TransTexas and the Production Payment Owners are executing and
delivering that certain Second Supplement to Production Payment Conveyance of
even date herewith (the "Second Supplement") which further supplements and
amends the Original Conveyance. A true and correct copy of the Second Supplement
is attached as Exhibit A hereto and made a part hereof. As used herein,
"Conveyance" means the Original Conveyance as amended and supplemented by the
First Supplement and the Second Supplement, and "Production Payment" has the
meaning given to such term in the Conveyance.

         4. Under the Indenture, the Production Payment constitutes "First Lien
Debt" secured by a "Permitted Lien" (as such terms are defined in the
Indenture). Pursuant to Section 11.2(c) of the Indenture, TransTexas has
delivered a "Subordination Request" to the Mortgage

                                                               Second Supplement

<PAGE>   2

Holder, asking the Mortgage Holder to enter into this Agreement in order to
subordinate the Mortgage Holder Liens to the Production Payment and the
Conveyance (after taking the Second Supplement into account), and TransTexas has
satisfied the conditions in such Section 11.2(c). (As used herein, "Mortgage
Holder Liens" means all liens, security interests, assignments (of production or
otherwise) and other rights or interests of the Mortgage Holder at any time
existing on or in any properties or assets of TransTexas which are in any way
subject to the Production Payment or the Conveyance, whether such liens,
security interests, assignments and other rights or interests arise under the
Indenture or the Security Documents or by operation of law or otherwise.)

         NOW, THEREFORE, in consideration of the foregoing, and in order to
induce the Production Payment Owners to enter into the Second Supplement and pay
funds to TransTexas in connection therewith, the Mortgage Holder and TransTexas
hereby agree as follows:

         Section 1. Subordination. The Production Payment and the proceeds
thereof are and hereafter shall be senior in right and priority to all Mortgage
Holder Liens, regardless of the relative priority of the Mortgage Holder Liens
and the Production Payment as determined without regard to this Agreement, and
the same shall have the same validity and effect as if the Conveyance (including
all supplements thereto) had been executed, delivered and properly recorded
prior to the date and time of execution of the Indenture and the date and time
of execution and recordation of the Security Documents. All references in
Section 9.2 of each Mortgage to the "Production Payment Conveyance" shall
hereafter refer to the Conveyance, as defined herein, and all references in
Section 9.2 of each Mortgage to the "Production Payment Conveyance" shall
henceforth refer to the Production Payment Conveyance, as defined herein. As so
modified, the terms of Section 9.2 of each Mortgage are hereby ratified and
confirmed.

         Section 2. Acknowledgment of Reliance. The parties acknowledge and
agree that Production Payment Owners have entered into the Second Supplement in
reliance on the priority of the Conveyance, and thus are relying on the waiver,
relinquishment and subordination set forth herein.

         Section 3. Governing Law. This Agreement shall be deemed a contract and
instrument made under the laws of the State of Texas and shall be construed and
enforced in accordance with and governed by the laws of such state and the laws
of the United States of America, without regard to principles of conflicts of
law.

         Section 4. Invalidity of Particular Provisions. If any term or
provision of this Agreement shall be determined to be illegal or unenforceable,
all other terms and provisions hereof shall nevertheless remain effective and
shall be enforced to the fullest extent permitted by applicable law.

         Section 5. Successors and Assigns. This Agreement shall pass to and be
fully binding upon and inure to the benefit of the successors and assigns of
each party hereto (including the Production Payment Owners).

                                                               Second Supplement

                                       2
<PAGE>   3

         Section 6. Counterparts. This Agreement may be separately executed in
any number of counterparts and by different parties hereto in separate
counterparts, each of which when so executed shall be deemed to constitute one
and the same instrument.

                  IN WITNESS WHEREOF, this Agreement is executed by the parties
hereto on the dates set out below in their respective acknowledgments, to take
effect as of the date first above written.

MORTGAGE HOLDER:                        FIRSTAR BANK, N.A.,
                                        as Trustee under the Indenture

                                        By:  /s/ FRANK P. LESLIE III
                                            ------------------------------------
                                            Name:   Frank P. Leslie III
                                                  ------------------------------
                                            Title:  Vice President
                                                   -----------------------------

TRANSTEXAS:                             TRANSTEXAS GAS CORPORATION

                                        By:  /s/ ED DONAHUE
                                            ------------------------------------
                                            Ed Donahue, Vice President

                                                               Second Supplement

                                       3
<PAGE>   4

STATE OF MINNESOTA       )
                         )
COUNTY OF RAMSEY         )

         The foregoing instrument was acknowledged before me on this 8th day of
September, 2000, by Frank P. Leslie III, as Vice President of Firstar Bank,
N.A., a national banking association, on behalf of such association in its
capacity as Trustee under the above-described Indenture.

         [SEAL]                               /s/ ALYSSA M. NGUYEN
                                             -----------------------------------
                                              Notary Public, State of Minnesota

My commission expires:

-------------------------

STATE OF TEXAS           )
                         )
COUNTY OF HARRIS         )

         The foregoing instrument was acknowledged before me on this 11th day of
September, 2000, by Ed Donahue as Vice President of TransTexas Gas Corporation,
a Delaware corporation, on behalf of such corporation.

         [SEAL]                               /s/ NANCY L. JAMES
                                             -----------------------------------
                                              Notary Public, State of Texas

My commission expires:

-------------------------

                                                               Second Supplement

                                       4
<PAGE>   5

                                   SCHEDULE 1
                                       TO
                             SUBORDINATION AGREEMENT

                        SCHEDULE OF TEXAS RECORDING DATA

                                  COUNTERPARTS
                                     OF THE
               MORTGAGE, DEED OF TRUST, ASSIGNMENT OF PRODUCTION,
                   SECURITY AGREEMENT AND FINANCING STATEMENT,
                           DATED AS OF MARCH 15, 2000,
            FROM TRANSTEXAS GAS CORPORATION, AS MORTGAGOR AND DEBTOR,
                         TO ROBERT M. GALPERIN, TRUSTEE,
                      FOR THE BENEFIT OF FIRSTAR BANK, N.A.
      IN ITS CAPACITY AS INDENTURE TRUSTEE, AS MORTGAGEE AND SECURED PARTY,
ARE RECORDED IN THE REAL PROPERTY RECORDS IN THE COUNTIES IN THE STATE OF TEXAS
                      AS SET FORTH IN THE FOLLOWING TABLE:

<TABLE>
<CAPTION>
==================================================================================================================================
                                                                               RECORDING DATA
    COUNTY IN WHICH                                (REFERENCE IS ALSO MADE TO THE "NOTE" IMMEDIATELY FOLLOWING THIS TABLE)
    COUNTERPART IS                        ----------------------------------------------------------------------------------------
       RECORDED               DATE                                                                          REFERENCE / FILE /
 (EACH IN THE STATE OF         OF                                                                              INSTRUMENT /
        TEXAS)              RECORDING        VOL/BK         PAGE(S)           FILM CODE NUMBER               DOCUMENT NUMBER
======================= ================= ============  ===============  ==========================  =============================
<S>                     <C>               <C>           <C>              <C>                         <C>
        AUSTIN              03/16/00                                                                               001522
----------------------- ----------------- ------------  ---------------  --------------------------  -----------------------------
       BRAZORIA             03/16/00                                                                             00010929
----------------------- ----------------- ------------  ---------------  --------------------------  -----------------------------
        CALHOUN             03/21/00            250               86                                              0062749
----------------------- ----------------- ------------  ---------------  --------------------------  -----------------------------
       CHAMBERS             03/17/00         00-449        190 - 303                                               1688-B
----------------------- ----------------- ------------  ---------------  --------------------------  -----------------------------
       COLORADO             03/16/00            330        834 - 930
----------------------- ----------------- ------------  ---------------  --------------------------  -----------------------------
       GALVESTON            03/17/00                                            ###-##-####                  GAC200001259
----------------------- ----------------- ------------  ---------------  --------------------------  -----------------------------
        HARRIS              03/21/00                                            ###-##-####                       U286247
----------------------- ----------------- ------------  ---------------  --------------------------  -----------------------------
        HIDALGO             03/21/00                                                                               856646
----------------------- ----------------- ------------  ---------------  --------------------------  -----------------------------
       JIM HOGG             03/20/00             17        701 - 797                                               64,586
----------------------- ----------------- ------------  ---------------  --------------------------  -----------------------------
         KENT               03/16/00              2              129                                                  180
----------------------- ----------------- ------------  ---------------  --------------------------  -----------------------------
       LIVE OAK             03/20/00            380        407 - 505                                             00147280
----------------------- ----------------- ------------  ---------------  --------------------------  -----------------------------
      SAN JACINTO           03/16/00        00-1612      5898 - 5985
----------------------- ----------------- ------------  ---------------  --------------------------  -----------------------------
         STARR              03/16/00           0858        001 - 154                                               207934
----------------------- ----------------- ------------  ---------------  --------------------------  -----------------------------
       VAL VERDE            03/21/00            737        336 - 423                                              0179838
----------------------- ----------------- ------------  ---------------  --------------------------  -----------------------------
         WEBB               03/21/00            891        418 - 506                                               690351
----------------------- ----------------- ------------  ---------------  --------------------------  -----------------------------
</TABLE>

                                                               Second Supplement

<PAGE>   6

<TABLE>
<CAPTION>
==================================================================================================================================
                                                                               RECORDING DATA
    COUNTY IN WHICH                                (REFERENCE IS ALSO MADE TO THE "NOTE" IMMEDIATELY FOLLOWING THIS TABLE)
    COUNTERPART IS                        ----------------------------------------------------------------------------------------
       RECORDED               DATE                                                                          REFERENCE / FILE /
 (EACH IN THE STATE OF         OF                                                                              INSTRUMENT /
        TEXAS)              RECORDING        VOL/BK         PAGE(S)           FILM CODE NUMBER               DOCUMENT NUMBER
======================= ================= ============  ===============  ==========================  =============================
<S>                     <C>               <C>           <C>              <C>                         <C>
       WHARTON              03/20/00            361          1 - 129
----------------------- ----------------- ------------  ---------------  --------------------------  -----------------------------
       ZAPATA               03/17/00            630          1 - 115                                               119228
----------------------- ----------------- ------------  ---------------  --------------------------  -----------------------------
</TABLE>

NOTE:    A COUNTERPART OF THE DEED OF TRUST REFERENCED ABOVE, WITH A COMPLETE
         EXHIBIT "A," IS RECORDED IN THE REAL PROPERTY RECORDS OF GALVESTON
         COUNTY, TEXAS, AS SET FORTH IN THE FOREGOING TABLE. AS TO THE
         COUNTERPARTS OF THE DEED OF TRUST REFERENCED ABOVE THAT ARE RECORDED IN
         THE REAL PROPERTY RECORDS OF OTHER COUNTIES IN THE STATE OF TEXAS (AS
         INDICATED IN THE TABLE ABOVE), THE EXHIBIT "A" ATTACHED TO EACH SUCH
         RECORDED COUNTERPART IDENTIFIES ONLY THOSE REAL PROPERTIES LOCATED IN
         THE COUNTY IN THE STATE OF TEXAS IN WHICH SUCH COUNTERPART IS RECORDED.
         FOR A COMPLETE LIST OF ALL REAL PROPERTIES IN ALL COUNTIES IN THE STATE
         OF TEXAS THAT ARE SUBJECT TO THE DEED OF TRUST REFERENCED ABOVE, REFER
         TO, AND REFERENCE IS HEREBY MADE FOR ALL PURPOSES TO, THE COUNTERPART
         OF THE DEED OF TRUST REFERENCED ABOVE THAT IS RECORDED IN THE REAL
         PROPERTY RECORDS OF GALVESTON COUNTY, TEXAS.

                          ADDITIONAL SECURITY DOCUMENTS

SECURITY AND PLEDGE AGREEMENT DATED AS OF MARCH 15, 2000, BY AND BETWEEN
TRANSTEXAS GAS CORPORATION, A DELAWARE CORPORATION, AS DEBTOR, AND FIRSTAR BANK,
N.A., IN ITS CAPACITY AS INDENTURE TRUSTEE FOR THE BENEFIT OF HOLDERS OF
TRANSTEXAS GAS CORPORATION'S 15% SENIOR SECURED NOTES DUE 2005.

FINANCING STATEMENT OF FORM UCC-1 FROM TRANSTEXAS GAS CORPORATION, AS DEBTOR, TO
FIRSTAR BANK, N.A., TRUSTEE, AS SECURED PARTY, FILED MARCH 27, 2000, IN THE
OFFICE OF THE SECRETARY OF STATE OF THE STATE OF TEXAS UNDER FILE NUMBER
0000460611.

                                                               Second Supplement

<PAGE>   7

                                    EXHIBIT A

                                       TO

                             SUBORDINATION AGREEMENT

               SECOND SUPPLEMENT TO PRODUCTION PAYMENT CONVEYANCE

                                                               Second Supplement

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00015-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00015-of-00352.parquet"}]]