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                                                                     Exhibit 5.1



                  Opinion of Orrick, Herrington & Sutcliffe LLP
                   With Respect to Securities Being Registered

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                                                                     Exhibit 5.1

               [Letterhead of Orrick, Herrington & Sutcliffe LLP]


                                          July 22, 1998


Banc One ABS Corporation
100 East Broad Street
Columbus, Ohio 43271-0158

Ladies and Gentlemen:

      We have acted as special counsel to Banc One ABS Corporation (the
"Registrant"), in connection with the preparation and filing with the Securities
and Exchange Commission (the "Commission") on July 22, 1998 of a Registration
Statement on Form S-3 (the "Registration Statement"), in connection with the
registration under the Securities Act of 1933, as amended (the "Act") of
Asset-Backed Securities (the "Securities"). The Securities are issuable in
series (each, a "Series") under either a separate Pooling and Servicing
Agreement, Trust Agreement or Indenture (each, an "Agreement") by and among the
Registrant, the Servicer named therein and the Trustee named therein. The
Securities of each Series are to be sold as set forth in the Registration
Statement, any amendment thereto, and the prospectus and prospectus supplement
relating to such Series.

      We have examined such instruments, documents and records as we deemed
relevant and necessary as a basis of our opinion hereinafter expressed. In such
examination, we have assumed the following: (a) the authenticity of original
documents and the genuineness of all signatures; (b) the conformity to the
originals of all documents submitted to us as copies; and (c) the truth,
accuracy and completeness of the information, representations and warranties
contained in the records, documents, instruments and certificates we have
reviewed.

      Based on such examination, we are of the opinion that when the issuance of
each Series of Securities has been duly authorized by appropriate corporate
action and the Securities of such Series have been duly executed, authenticated
and delivered in accordance with the Agreement relating to such Series and sold
in the manner described in the Registration Statement and the prospectus and
prospectus supplement relating thereto, the Securities of such Series will be
legally issued, fully paid, binding obligations of the trust created by each
Agreement and the holders of the Securities of such Series will be entitled to
the benefits of the related Agreement, except as enforcement thereof may be
limited by applicable bankruptcy, insolvency, reorganization, arrangement,
fraudulent conveyance, moratorium, or other laws relating to or affecting the
rights of creditors generally and

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Banc One ABS Corporation
July 22, 1998
Page 2


general principles of equity, including without limitation, concepts of
materiality, reasonableness, good faith and fair dealing, and the possible
unavailability of specific performance or injunctive relief, regardless of
whether such enforceability is considered in a proceeding in equity or at law.

      In rendering the foregoing opinions, we express no opinion as to the laws
of any jurisdiction other than the State of New York and the Federal laws of the
United States of America.

      We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the use of our name wherever appearing in the
Registration Statement and the prospectus contained therein, as supplemented by
the prospectus supplement related to a series of Securities. In giving such
consent, we do not consider that we are "experts," within the meaning of the
term as used in the Act or the rules and regulations of the Commission issued
thereunder, with respect to any part of the Registration Statement, including
this opinion as an exhibit or otherwise.


                                    Very truly yours,

                                    /s/ ORRICK, HERRINGTON & SUTCLIFFE LLP

                                    ORRICK, HERRINGTON & SUTCLIFFE LLP