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                                October 24, 2002





(303) 298-5700                                                    C 18591-00034

CSK Auto Corporation
645 E. Missouri Avenue
Suite 400
Phoenix, Arizona  85012

         Re:      Registration Statement on Form S-3

Ladies and Gentlemen:

         We have acted as special counsel for CSK Auto Corporation, a Delaware
corporation (the "Company"), in connection with registration under the
Securities Act of 1933, as amended, of 3,041,967 shares of the Company's Common
Stock, par value $0.01 per share (the "Common Stock"), to be sold by the three
selling stockholders (the "Selling Stockholders' Shares") named in the
Registration Statement on Form S-3 (the "Registration Statement") to be filed by
the Company with the Securities and Exchange Commission in connection with such
registration. The selling stockholders propose to sell the Selling Stockholders'
Shares pursuant to the Plan of Distribution set forth in the Registration
Statement.

         We have examined the originals, or photostatic or certified copies, of
such records of the Company and certificates of officers of the Company and of
public officials and such other documents as we have deemed relevant and
necessary as the basis for the opinions set forth below. In such examination, we
have assumed the genuineness of all signatures, the authenticity of all
documents submitted to us as originals, the conformity to original documents of
all documents submitted to us as certified or photostatic copies and the
authenticity of the originals of such copies.

                  Based on the foregoing and in reliance thereon, and subject to
the assumptions, exceptions, qualifications and limitations set forth herein, we
are of the opinion that the Selling Stockholders' Shares have been validly
issued and are fully paid and non-assessable.

         We render no opinion herein as to matters involving the laws of any
jurisdiction other than the laws of the United States of America and the General
Corporation Law of the State of Delaware. We are not admitted to practice in the
State of Delaware; however, we are generally
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CSK Auto Corporation
October 24, 2002
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familiar with the Delaware General Corporation Law as presently in effect and
have made such inquiries as we consider necessary to render the foregoing
opinion. In rendering this opinion, we assume no obligation to revise or
supplement this opinion should current laws, or the interpretations thereof, be
changed.

         We consent to the filing of this opinion as an exhibit to the
Registration Statement, and we further consent to the use of our name under the
caption "Legal Matters" in the Registration Statement and the prospectus which
forms a part thereof. In giving these consents, we do not thereby admit that we
are within the category of persons whose consent is required under Section 7 of
the Securities Act or the Rules and Regulations of the Commission.


                                                 Very truly yours,

                                                 /s/ Gibson, Dunn & Crutcher LLP

                                                 GIBSON, DUNN & CRUTCHER LLP
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CSK Auto Corporation
October 24, 2002
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RMR/SKT/JMF/LSL

