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                                                                 EXHIBIT 4.28

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                        TRANSAMERICAN ENERGY CORPORATION


               $475,000,000 11 1/2% Senior Secured Notes due 2002

                                      and

           $1,130,000,000 13% Senior Secured Discount Notes due 2002


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

                FIRST AMENDMENT TO REGISTRATION RIGHTS AGREEMENT

                         Dated as of December 30, 1997

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



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       This First Amendment to Registration Rights Agreement (this "First
Amendment") is made as of December 30, 1997, by and among TransAmerican Energy
Corporation, a Delaware corporation ("TEC"), TransTexas Gas Corporation, a
Delaware corporation ("TransTexas"), TransAmerican Refining Corporation, a
Texas corporation ("TARC"), and Jefferies & Company, Inc. (the "Purchaser").
Capitalized terms used but not defined herein shall have the meaning attributed
to them in that certain Registration Rights Agreement, dated as of June 5,
1997, among TEC, TransTexas, TARC, and the Purchaser (the "Registration Rights
Agreement").

       WHEREAS, TEC and Firstar Bank of Minnesota, N.A., as Trustee, have
entered into an Indenture dated as of June 13, 1997 (the "Indenture"), pursuant
to which TEC issued (i) $475,000,000 aggregate principal amount of its 11 1/2%
Senior Secured Notes due 2002, Series A, and (ii) $1,130,000,000 aggregate
principal amount of its 13% Senior Secured Discount Notes due 2002, Series A
(collectively, the "Notes"); and

       WHEREAS, as an inducement to the Purchaser to enter into the Purchase
Agreement (as defined in the Registration Rights Agreement), TEC, TransTexas
and TARC entered into the Registration Rights Agreement with the Purchaser for
the benefit of the Holders of the Securities; and

       WHEREAS, the parties to the Registration Rights Agreement have agreed to
certain amendments to the Registration Rights Agreement as hereinafter set
forth (the "Proposed Amendments"); and

       WHEREAS, in accordance with the provisions of Section 11(c) of the
Registration Rights Agreement, the written consent of the of Holders of at
least a majority of the then outstanding aggregate principal amount of
Registrable Securities to the adoption of the Proposed Amendments have been
obtained;

       NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties to this First
Amendment hereby agree as follows:

                                   ARTICLE I

                   AMENDMENT TO REGISTRATION RIGHTS AGREEMENT

       Section 1.01.  Section 4 of the Registration Rights Agreement.  Section
4(a)(iii) of the Registration Rights Agreement is hereby amended to read in its
entirety as follows:

              (iii)  if the Company has not accepted for exchange all Notes
       validly tendered in accordance with the terms of the Exchange Offer
       within 30 business days after the date on which an Exchange Offer
       Registration Statement is declared effective by the SEC; or

                                   ARTICLE II

                                 MISCELLANEOUS

       Section 2.01.  Ratification and Confirmation.  As amended and modified
by this First Amendment, the terms and provisions of the Registration Rights
Agreement are hereby ratified and confirmed and shall continue in full force
and effect.





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       Section 2.02.  Reference to Registration Rights Agreement.  The
Registration Rights Agreement and any and all other agreements, documents or
instruments now or hereafter executed and delivered pursuant to the terms of
the Registration Rights Agreement, are hereby amended so that any reference
therein to the Registration Rights Agreement shall mean a reference to the
Registration Rights  Agreement as amended hereby.

       Section 2.03.  Counterparts.  This First Amendment may be executed in
one or more counterparts, each of which when executed shall be deemed to be an
original, but all of which when taken together shall constitute one and the
same instrument.

       Section 2.04.  Headings.  The headings, captions and arrangements used
in this First Amendment are for convenience only and shall not affect the
interpretation of this First Amendment.

       Section 2.05. Governing Law.  THIS FIRST AMENDMENT SHALL BE CONSTRUED IN
ACCORDANCE WITH AND GOVERNED BY THE LAWS OF THE STATE OF NEW YORK, WITHOUT
REGARD TO PRINCIPLES OF CONFLICTS OF LAWS.

       IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed as of the date of first written above.





                              TRANSAMERICAN ENERGY CORPORATION



                              By:
                                 --------------------------------------
                              Name:
                                   ------------------------------------
                              Title:
                                    -----------------------------------



                              TRANSTEXAS GAS CORPORATION



                              By:
                                 --------------------------------------
                              Name:
                                   ------------------------------------
                              Title:
                                    -----------------------------------




                              TRANSAMERICAN REFINING CORPORATION



                              By:
                                 --------------------------------------
                              Name:
                                   ------------------------------------
                              Title:
                                    -----------------------------------





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Accepted and Agreed to:

JEFFERIES & COMPANY, INC.


By:
   --------------------------------------
Name:
     ------------------------------------
Title:
      -----------------------------------





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