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                                                                     EXHIBIT 5.1







                                January 18, 1999


     TransAmerican Refining Corporation
     1300 North Sam Houston Parkway East
     Suite 320
     Houston, Texas  77032-2949

     Gentlemen:

             We have served as counsel for TransAmerican Refining Corporation, a
     Texas corporation (the "COMPANY"), in connection with the Registration
     Statement on Form S-4 (the "REGISTRATION STATEMENT") filed with the
     Securities and Exchange Commission in connection with the registration
     under the Securities Act of 1933, as amended (the "1933 ACT"), of
     $200,000,000 principal amount of the Company's 16% Series B Senior
     Subordinated Notes due 2003 (the "NOTES") to be offered in exchange for the
     Company's outstanding $175,000,000 principal amount 16% Series A Senior
     Subordinated Notes due 2003 and $25,000,000 principal amount 16% Series C
     Senior Subordinated Notes due 2003.

             We have examined the Registration Statement, the Indenture between
     the Company and First Union National Bank, as Trustee, pursuant to which
     the Notes are to be issued (the "INDENTURE"), the form of the Notes to be
     issued and such other documents and such questions of law as we have deemed
     necessary to render the opinion expressed below.

             In our examination, we have assumed the genuineness of all
     signatures, the legal capacity of all natural persons, the authenticity of
     all documents submitted to us as originals, the conformity to original
     documents of all documents submitted to us as copies, and the authenticity
     of the originals of such copied documents. We have also assumed, with
     respect to all persons and entities other than the Company, the power
     (corporate or otherwise) of such persons or entities to enter into and
     perform all of their obligations under the Indenture, the due authorization
     by all requisite action (corporate or otherwise) on the part of such
     persons or entities, the due execution and delivery by such persons or
     entities of such document, and the validity and binding effect thereof. As
     to any facts material to the opinion expressed herein that we did not
     independently establish or verify, we have relied upon oral or written
     statements, certificates and representations of officers and other
     representatives of the Company and others.



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             Based upon the foregoing, and subject to the qualifications set
     forth below, we are of the opinion that when the Notes are executed and
     authenticated in accordance with the terms of the Indenture and delivered
     in the manner and for the consideration described in the Registration
     Statement, the Notes will be binding and enforceable obligations of the
     Company.

             The opinion expressed above is subject to the following
     qualifications:

             A. The binding nature and enforceability of the Notes may be
     limited by (i) bankruptcy, insolvency, reorganization, moratorium,
     fraudulent conveyance or transfer, and other similar laws affecting the
     enforcement of creditors' rights generally and (ii) equitable principles of
     general application and judicial discretion that may limit or affect the
     availability or grant of certain equitable remedies in certain instances.
     In addition, the binding nature and enforceability of certain of the
     remedial, waiver and other provisions of the Notes, or of the Indenture for
     the Notes, may be restricted by applicable state law, but such restrictions
     will not, in our opinion, render the Notes invalid as a whole or
     substantially interfere with the realization of the principal legal
     benefits purported to be provided by the Notes or by the Indenture for the
     Notes (except to the extent of any procedural delay which may result
     therefrom). Further, the binding nature and enforceability of the
     indemnification provisions of the Indenture may be limited by public
     policies embodied in or reflected by various state and federal securities
     laws.

             B. The opinion expressed herein is limited to the laws of the
     United States of America and the laws of the State of Texas, and we assume
     no responsibility as to the applicability or the effect of any other laws.
     We have assumed that the laws of the State of New York, which purport to
     govern the Notes and the Indenture, are the same as the laws of the State
     of Texas with respect to the binding nature and enforceability of the
     Notes.

             We consent to the use of this opinion letter as an exhibit to the
     Registration Statement and to the use of our name in the Registration
     Statement under the heading "Legal Matters." Our consent, however, is not
     an admission that we come within the category of persons whose consent is
     required under Section 7 of the 1933 Act or the rules and regulations of
     the Securities and Exchange Commission.

                                           Very truly yours,

                                           GARDERE & WYNNE, L.L.P.


                                           By: /s/ C. ROBERT BUTTERFIELD
                                               ---------------------------------
                                                C. Robert Butterfield, Partner