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                    [Gibson, Dunn & Crutcher LLP letterhead]

                            [                , 1998]





(212) 351-4000                                                      18591-00011

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

         Re:     CSK Auto Corporation Registration Statement on Form S-1
                 (File No. 333-43211)

Ladies and Gentlemen:

         We have examined the Registration Statement on Form S-1, File No.
333-43211 (the "Registration Statement"), of CSK Auto Corporation, a Delaware
corporation (the "Company"), filed with the Securities and Exchange Commission
(the "Commission") pursuant to the Securities Act of 1933, as amended (the
"Securities Act"), in connection with the public offering by the Company of up
to 8,625,000 newly issued shares (the "Shares") of the Common Stock, par value
$.01 per share, of the Company.

         For the purpose of the opinion set forth below, we have examined and
are familiar with the proceedings taken and proposed to be taken by the Company
in connection with the sale of the Shares, including, among other things, such
corporate 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 opinion 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 upon the foregoing examination and in reliance thereon, and
subject to the assumptions stated and in reliance on statements of fact
contained in the documents that we have
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CSK Auto Corporation
[            , 1998]
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examined and subject to the completion of the proceedings to be taken by the
Company prior to the sale of the Shares, it is our opinion that, when the
Registration Statement has become effective under the Securities Act and the
Shares have been issued and sold as contemplated in the Registration Statement
and duly delivered, the Shares will be validly issued, 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.  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


