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                                                                     EXHIBIT 5.1

                            [AMY WATERS LETTERHEAD]


   
                                October 30, 1998


U.S. Automobile Acceptance SNP-IV, Inc.
1120 N.W. 63rd
Suite G-106
Oklahoma City, Oklahoma 73116
    

Gentlemen:

         Reference is hereby made to the Registration Statement on Form S-1,
File No. 333-44189 (the "Registration Statement"), of U.S. Automobile SNP-IV,
Inc., a Texas corporation (the "Company"), filed under the Securities Act of
1933, as amended (the "Act"), covering the proposed issuance and sale of up to
$40,000,000 aggregate principal amount of Asset-Backed Promissory Notes (the
"Notes"), to be issued under an indenture (the "Indenture") to be entered into
between the Company and Sterling Trust Company, as trustee (the "Trustee").

   
         In connection therewith, I have reviewed originals or copies
authenticated to my satisfaction of all documents, certificates, records and
instruments of the Company which I believe are necessary or appropriate in
rendering this opinion, including (i) the Certificate of Incorporation and
By-Laws of the Company, (ii) the Minute Book of the Company containing the
minutes of directors' and shareholders' meetings and actions, (iii) the
Registration Statement and all exhibits thereto, including the proposed forms
of the Notes and the Indenture, and (iv) such certificates of public officials
and of officers of the Company as I have deemed necessary as a basis for the
opinions herein expressed.  As to some questions of fact material to these
opinions, I have, where relevant facts were not independently established,
relied upon a certificate of officers of the Company.
    

         Based upon the foregoing, I am of the opinion that:

   
         1.      The Company is a corporation duly incorporated and validly
existing under the laws of the State of Texas, pursuant to the Texas Business
Corporation Act.
    

   
         2.      The Indenture and the Notes have been validly authorized by
the Company.  After the Indenture has been duly executed and delivered on
behalf of the Company and the Trustee named therein, the Notes, when executed,
authenticated, issued and delivered, and sold as contemplated by the
Registration Statement, will be legally issued under the Texas Business
Corporation Act, and the Federal Securities Act of 1933, as amended, and will
constitute valid and binding obligations of the Company.
    
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U.S. Automobile Acceptance SNP-IV, Inc.
October 30, 1998
Page 2
    





         I hereby consent to the filing of this opinion with the Securities and
Exchange Commission as an exhibit to the Registration Statement and to the
reference to this firm under the heading "Legal Matters" in the Prospectus
included therein.  This letter consent does not constitute a consent under
Section 7 of the Act, and in permitting my name to appear under the heading
"Legal Matters" I have not certified any part of the Registration Statement,
or, except in connection with the filing of this opinion, otherwise come within
the category of persons whose consent is required under Section 7 or under the
rules or regulations of the Securities and Exchange Commission.

                                                   Sincerely,



                                                   Amy Waters