THIRD AMENDMENT

THIRD AMENDMENT, dated as of October 10, 2007 (this “Amendment”), to the CREDIT
AGREEMENT dated as of June 30, 2006 (as amended, supplemented or modified from
time to time, the “Credit Agreement”) among CSK AUTO, INC., the Lenders party
thereto, and JPMORGAN CHASE BANK, N.A., as Administrative Agent., and LEHMAN
COMMERCIAL PAPER INC. and WACHOVIA BANK, NATIONAL ASSOCIATION, as Co-Syndication
Agents.

W I T N E S S E T H:

WHEREAS, the Company, the Administrative Agent, the Co-Syndication Agents and
the Lenders are parties to the Credit Agreement;

WHEREAS, the parties hereto have agreed to amend the Credit Agreement upon the
terms and conditions set forth herein;

NOW, THEREFORE, for valuable consideration, the receipt and sufficiency of which
are hereby acknowledged, and in consideration of the premises contained herein,
the parties hereto agree as follows:

1. Defined Terms. Unless otherwise defined herein, capitalized terms which are
defined in the Credit Agreement are used herein as defined therein.

2. Amendments to Credit Agreement.

(a) Amendments to Section 1.01. Effective upon the Effective Date (as defined
below), Section 1.01 of the Credit Agreement is hereby amended by:

(i) deleting the definition of “Applicable Rate” where it appears therein, and
inserting in lieu thereof, the following new definition:

“Applicable Rate” means, for any day, with respect to any Eurodollar Loan or ABR
Loan, the applicable rate per annum set forth below under the caption
“Eurodollar Spread” or “ABR Spread” as applicable, based upon the then current
corporate ratings issued by Moody’s and S&P for the Company, and provided, that
if at any time either of Moody’s or S&P does not have or withdraws its rating on
the Company, for the purposes hereof, the rating shall be deemed to be B3 or B-,
as the case may be:

                                      Rating   Eurodollar Spread   ABR Spread  
     
 
  >=Ba3/BB-     3.25 %     2.25 %        
 
    B1/B+       3.50 %     2.50 %        
 
    B1/B       3.75 %     2.75 %        
 
    B2/B       4.00 %     3.00 %        
 
    <=B3/B-       4.50 %     3.50 %        

If the Company has at any time a split rating (other than B1/B) then the lower
rating shall apply. If any Event of Default shall have occurred and be
continuing as of any date on which the Applicable Rate would have otherwise been
adjusted in accordance with this definition, the Applicable Rate shall in no
event be reduced on such date (from the Applicable Rate as in effect prior to
such date) until such Event of Default is cured or waived.

(ii) inserting the following new definitions in appropriate alphabetical order:

“Third Amendment” means the third amendment, dated as of October 10, 2007, to
this Agreement.

“Third Amendment Effective Date” means October 10, 2007.

(b) Amendment to Section 2.05. Section 2.05 of the Credit Agreement is hereby
amended by (i) inserting the words “(other than any credit facility incurred, or
repricing effected, concurrently with a Change of Control)” after the word
“Loans” where it first appears in the second proviso thereof; and (ii) deleting
the term “Closing Date” where it appears in the second proviso thereof and
inserting “Third Amendment Effective Date” in lieu thereof.

(c) Amendment to Section 6.07(b). Effective upon the Effective Date,
Section 6.07(b) of the Credit Agreement is hereby amended by deleting such
Section in its entirety and inserting in lieu thereof the following new Section:

“(b) As of the last day of the fiscal quarter ending on or about the date set
forth below, permit the Leverage Ratio to be greater than the ratio set forth
opposite such date below:

                      Quarter   Dates   Leverage Ratio    
 
  Q4 ‘06   February 4, 2007   3.75:1.00    
 
  Q1 ‘07   May 6, 2007   3.95:1.00    
 
  Q2 ‘07   August 5, 2007   3.85:1.00    
 
  Q3 ‘07   November 4, 2007   4.00:1.00    
 
  Q4 ‘07   February 3, 2008   4.00:1.00    
 
  Q1 ‘08   May 4, 2008   3.85:1.00    
 
  Q2 ‘08   August 3, 2008   3.75:1.00    
 
  Q3 ‘08   November 2, 2008   3.50:1.00    
 
   
 
 
Q4 ‘08 — Q3 ‘09   February 1, 2009,
May 3, 2009, August
2, 2009 and
November 1, 2009    
 
 
3.25:1.00  

 
 
   
 
Q4 ’09 – maturity   January 31, 2010
and any time
thereafter    
 
3.00:1.00  

 

3. Conditions to Effectiveness of this Amendment. This Amendment shall become
effective on the date (the “Effective Date”), upon which the Administrative
Agent shall have received (i) counterparts of this Amendment duly executed by
the Company, the Guarantors, the Administrative Agent and the Required Lenders,
(ii) payment, for distribution to each Lender that has signed and delivered this
Amendment to the Administrative Agent by not later than 5:00 p.m. (New York City
time) on October 10, 2007 (or such later time or date as agreed by the Company
and the Administrative Agent), an amendment fee equal to 0.25% of the
outstanding Loans of such Lender, and (iii) payment of all fees and invoiced
out-of-pocket costs and expenses of the Administrative Agent payable by the
Company under the Credit Documents and as otherwise agreed, including without
limitation, the reasonable fees and expenses of counsel to the Administrative
Agent.

4. Representations and Warranties; No Default; Limited Effect.

(a) Representations and Warranties. After giving effect to this Amendment, the
Company and the Guarantors hereby represent and warrant that all representations
and warranties contained in the Credit Agreement and the other Credit Documents
are true and correct in all material respects on and as of the Effective Date
(unless stated to relate to a specific earlier date, in which case, such
representations and warranties shall be true and correct in all material
respects as of such earlier date) and that no Default or Event of Default shall
have occurred and be continuing or would result from the execution and delivery
of this Amendment.

(b) Limited Effect. Except as expressly modified by this Amendment, the Credit
Agreement and the other Credit Documents are ratified and confirmed and are, and
shall continue to be, in full force and effect in accordance with their
respective terms. Each Credit Party acknowledges and agrees that such Credit
Party is truly and justly indebted to the Lenders and the Administrative Agent
for the Obligations, without defense, counterclaim or offset of any kind, and
such Credit Party ratifies and reaffirms the validity, enforceability and
binding nature of such Obligations. The Company acknowledges and agrees that
nothing in this Amendment shall constitute an indication of the Lenders’
willingness to consent to any other amendment or waiver of any other provision
of the Credit Agreement or a waiver of any Default or Event of Default.

5. Counterparts. This Amendment may be executed by one or more of the parties to
this Amendment on any number of separate counterparts (including by telecopy),
and all of said counterparts taken together shall be deemed to constitute one
and the same instrument. A set of the copies of this Amendment signed by the
parties hereto shall be delivered to the Company and the Administrative Agent.
The execution and delivery of this Amendment by any Lender, or by the
Administrative Agent with the consent of any Lender, shall be binding upon such
Lender’s successors and assigns (including transferees of its commitments and
Loans in whole or in part prior to effectiveness hereof) and binding in respect
of all of its commitments and Loans, including any acquired subsequent to its
execution and delivery hereof and prior to the effectiveness hereof.

6. Acknowledgement of Guarantors. The Guarantors acknowledge and consent to all
of the terms and conditions of this Amendment and agree that this Amendment and
all documents executed in connection herewith do not operate to reduce or
discharge the Guarantors’ obligations under the Credit Agreement or the other
Credit Documents. The Guarantors further acknowledge and agree that the
Guarantors have no claims, counterclaims, offsets, or defenses (other than
payment) to the Credit Documents and the performance of the Guarantors’
obligations thereunder or if the Guarantors did have any such claims,
counterclaims, offsets or defenses (other than payment) to the Credit Documents
or any transaction related to the Credit Documents, the same are hereby waived,
relinquished and released in consideration of execution and delivery of this
Amendment.

7. Credit Document. This Amendment is a Credit Document executed pursuant to the
Credit Agreement and shall (unless otherwise expressly indicated herein) be
construed, administered and applied in accordance with the terms and provisions
of the Credit Agreement.

8. GOVERNING LAW. THIS AMENDMENT AND THE RIGHTS AND OBLIGATIONS OF THE PARTIES
UNDER THIS AMENDMENT SHALL BE GOVERNED BY, AND CONSTRUED AND INTERPRETED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

* * * * *

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IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be executed
and delivered by their respective duly authorized officers as of the date first
above written.

CSK AUTO, INC.

By: /s/ STEPHEN LEWIS
Name: STEVEN LEWIS
Title: VP, TREASURER

Acknowledged

CSK AUTO CORPORATION

By: /s/ STEPHEN LEWIS
Name: STEVEN LEWIS
Title: VP, TREASURER

CSKAUTO.COM, INC.

By: /s/ STEPHEN LEWIS
Name: STEVEN LEWIS
Title: VP, TREASURER

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JPMORGAN CHASE BANK, N.A. as Administrative Agent and

a Lender

By: /s/ BARRY BERGMAN
Name: BARRY BERGMAN
Title: MANAGING DIRECTOR

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