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                                                                    EXHIBIT 5.01

                   [LETTERHEAD OF GIBSON, DUNN & CRUTCHER LLP]

                                  May 13, 2002

(212) 351-4000                                                     C 18591-00032

CSK Auto, Inc.
645 East Missouri Avenue
Phoenix, Arizona  85012

         Re:      CSK Auto, Inc.
                  Registration Statement on Form S-4

Ladies and Gentlemen:

         We have acted as special counsel to CSK Auto, Inc., an Arizona
corporation (the "Issuer"), CSK Auto Corporation, a Delaware corporation and the
parent of the Issuer ("Parent"), CSKAUTO.com, a Delaware corporation and a
wholly owned subsidiary of the Issuer ("Auto.com"), and Automotive Information
Systems, Inc., a Minnesota corporation and a wholly owned subsidiary of the
Issuer ("AIS" and collectively with Parent and Auto.com, the "Guarantors"), in
connection with the Issuer's registration, on a Registration Statement on Form
S-4 (the "Registration Statement"), under the Securities Act of 1933, as
amended, of $280,000,000 aggregate principal amount of 12% Senior Notes due 2006
(the "New Notes"), which are to be guaranteed pursuant to guarantees (the
"Guarantees") issued by the Guarantors.

         The New Notes will be offered in exchange for like principal amounts of
the Issuer's outstanding 12% Senior Notes due 2006 (the "Old Notes") pursuant to
the Notes Registration Rights Agreement, dated as of December 21, 2001 (the
"Registration Rights Agreement"), among the Issuer, the Guarantors, Credit
Suisse First Boston Corporation, J.P. Morgan Securities Inc., and UBS Warburg
LLC. The Registration Rights Agreement was executed in connection with the
private placement of the Old Notes.

         The New Notes will be, and the Guarantees were, issued pursuant to the
Indenture, dated as of December 21, 2001 (the "Indenture"), by and among the
Issuer, the Guarantors, and the Bank of New York, as Trustee. The New Notes, the
Guarantees and the Indenture are each



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governed under the internal law of the State of New York, and are sometimes
collectively referred to herein as the "Documents."

         In rendering this opinion, we have examined the Documents, and have
also made such inquiries and examined, among other things, originals or copies,
certified or otherwise identified to our satisfaction, of such records,
agreements, certificates, instruments and other documents, as we have considered
necessary or appropriate for purposes of this opinion.

         In rendering this opinion, we have assumed:

         (a) Each party to the Documents (i) is a validly existing corporation
in good standing under the laws of its state of incorporation, (ii) has all
requisite power and authority to execute, deliver and perform its obligations
under the Documents, (iii) has duly authorized, by all necessary action on such
party's part, the execution and delivery of each such Document and the
performance of such obligations and (iv) has duly executed and delivered each
such Document;

         (b) Each of the Documents is the legal, valid and binding obligation
of, and is enforceable against, each party thereto (other than the Issuer and
the Guarantors, as to which the assumptions in this clause (b) do not apply) in
accordance with its terms;

         (c) The signatures on all documents examined by us are genuine, all
individuals executing such documents had all requisite legal capacity and
competency and were duly authorized to execute and deliver such documents, the
documents submitted to us as originals are authentic, and the documents
submitted to us as certified or reproduction copies conform to the originals;

         (d) There are no agreements or understandings between or among the
Company and the Guarantors and other parties to the Documents, or third parties,
that would expand, modify or otherwise affect the terms of the Documents or the
respective rights or obligations of the parties thereunder;

         (e) The proceeds from the sale of the Old Notes were applied as set
forth in the Offering Circular; and

         (f) The issuance and delivery of the New Notes and the Guarantees will
not, at any time, violate any applicable law or result in a violation of any
provision of any instrument or agreement then binding on the Issuer or any
Guarantor or any restriction imposed by any court or governmental body having
jurisdiction over the Issuer or any Guarantor.

         Based upon the foregoing and in reliance thereon, and subject to the
assumptions, exceptions, qualifications and limitations contained herein, we are
of the opinion that:

                  (i) when issued in exchange for the Old Notes pursuant to the
         terms of the Indenture and the exchange offer described in the
         Registration Statement, the New Notes will be legally issued and will
         constitute binding obligations of the Issuer; and

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                  (ii) each Guarantee has been legally issued and constitutes a
         binding obligation of the respective Guarantor.

         The foregoing opinions are subject to the following exceptions,
qualifications and limitations:

                  A. Our opinions are subject to (i) the effect of any
         bankruptcy, insolvency, reorganization, moratorium, arrangement or
         similar laws affecting the rights and remedies of creditors' generally
         (including, without limitation, the effect of statutory or other laws
         regarding fraudulent transfers or preferential transfers) and (ii)
         general principles of equity, including without limitation concepts of
         materiality, reasonableness, good faith and fair dealing and the
         possible unavailability of specific performance, injunctive relief or
         other equitable remedies regardless of whether enforceability is
         considered in a proceeding in equity or at law.

                  B. We express no opinion regarding the effectiveness (i) of
         any waiver (whether or not stated as such) under the Documents, or any
         consent thereunder relating to, any unknown future rights or the rights
         of any party thereto existing, or duties owing to it, as a matter of
         law; (ii) of any waiver (whether or not stated as such) contained in
         the Documents of rights of any party, or duties owing to it, that is
         broadly or vaguely stated or does not describe the right or duty
         purportedly waived with reasonable specificity; (iii) of provisions
         relating to indemnification, exculpation or contribution, (iv) of any
         provisions of the Documents that may be construed as penalties or
         forfeitures; or (v) of any covenants (other than covenants relating to
         the payment of principal, interest, premium, indemnities and expenses)
         in the Indenture to the extent they are construed to be independent
         requirements as distinguished from conditions to the declaration or
         occurrence of a default or any event of default.

                  C. We express no opinion as to the effect on the
         enforceability of the Guarantees against the Guarantors of any facts or
         circumstances that would constitute a defense to the obligation of a
         guarantor or surety, unless such defense has been waived effectively by
         the Guarantors.

                  D. We render no opinion herein as to matters involving the
         laws of any jurisdiction other than the State of New York and the
         United States of America, and this opinion is limited to the effect of
         the present state of the laws of the State of New York and the United
         States of America. We assume no obligation to revise or supplement this
         opinion in the event of changes in such laws or the interpretations
         thereof or in the event of changes in such facts.

                  F. We express no opinion as to the applicability to, or the
         effect of noncompliance by, the holders of the New Notes or the Trustee
         with any state or federal laws applicable to the transactions
         contemplated by the Documents because of the nature of the business of
         such party.

         We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to this firm under the heading
"Legal Matters" contained in the prospectus


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that forms a part of the Registration Statement. In giving this consent, we do
not admit that we are within the category of persons whose consent is required
under Section 7 of the Securities Act of 1933, as amended, or the rules and
regulations promulgated thereunder.

                                                 Very truly yours,

                                                 /s/ Gibson, Dunn & Crutcher LLP

                                                 GIBSON, DUNN & CRUTCHER LLP

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