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                                                                     Exhibit 5.1

                                  June 17, 2002





(303) 298-5700                                                     C 18591-00030

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

         Re:  Registration Statement on Form S-3
              Registration No. 333-89982

Ladies and Gentlemen:

         We have acted as counsel for CSK Auto Corporation, a Delaware
corporation (the "Company"), in connection with the public offering of up to
12,976,562 shares of the Company's Common Stock, par value $0.01 per share (the
"Common Stock"), including (i) up to 7,334,595 shares of Common Stock to be sold
by the Company (the "Company Shares"), of which 1,692,595 shares of Common Stock
are subject to an over-allotment option granted to the Underwriters (as defined
below) by the Company, and (ii) 5,641,967 shares of Common Stock to be sold by
three selling stockholders (the "Selling Stockholders' Shares"), each pursuant
to Registration Statement No. 333-89982 on Form S-3, as amended (the
"Registration Statement"), under the Securities Act of 1933, as amended. The
Company proposes to issue and sell the Company Shares and the selling
stockholders propose to sell the Selling Stockholders' Shares to a group of
underwriters (the "Underwriters") represented by Merrill Lynch, Pierce, Fenner &
Smith Incorporated, UBS Warburg LLC, Credit Suisse First Boston Corporation and
Goldman, Sachs & Co.

         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.



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CSK Auto Corporation
June 17, 2002
Page 2


         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:

               1. The Selling Stockholders' Shares have been validly issued and
are fully paid and non-assessable; and

               2. When the price or prices and the other terms of sale of the
Company Shares have been determined as so authorized by the Company's Board of
Directors, the underwriting agreement or similar agreement for the Company
Shares has been duly authorized, executed and delivered by the parties thereto,
and the Company Shares have been issued and paid for in the manner contemplated
in the Registration Statement, the Company Shares will be validly issued, fully
paid and nonassessable.

         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 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 & Cruthcher LLP

                                                     GIBSON, DUNN & CRUTCHER LLP







