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Exhibit 10.3

AMENDMENT NO. 3 TO
STOCK PURCHASE AGREEMENT

    This Amendment No. 3 to Stock Purchase Agreement (this "Amendment") is
entered into as of October 19, 2001 by and between ATC Distribution Group, Inc.,
a Delaware corporation (the "Company"), and Aftermarket Technology Corp., a
Delaware corporation ("Seller").

    WHEREAS, ATCDG Acquisition Corp., Inc. ("Acquisition Corp.") and Seller
entered into a Stock Purchase Agreement, dated as of September 1, 2000 (as
amended to the date hereof, the "Stock Purchase Agreement"), pursuant to which
Acquisition Corp. acquired all of the outstanding capital stock of the Company
on October 27, 2000. Terms not otherwise defined herein shall have the meanings
ascribed to them in the Stock Purchase Agreement.

    WHEREAS, following such purchase Acquisition Corp. was merged with and into
the Company and the Company succeeded to all the rights and obligations of
Acquisition Corp. under the Stock Purchase Agreement.

    WHEREAS, the Company and Seller deem it desirable and in their best
interests to amend the Stock Purchase Agreement.

    NOW, THEREFORE, in consideration of the foregoing premises and the mutual
covenants and agreements hereinafter set forth, the parties hereto agree as
follows:

    1.  Amendment to Section 5.10(a).  Section 5.10(a) of the Stock Purchase
Agreement is hereby amended to read in its entirety as follows:

    "(a) During the period beginning on the Closing Date and ending on the fifth
anniversary of the Closing Date (the "Non-Compete Period") Seller shall not, and
will cause its Subsidiaries not to, sell anywhere in the world (and Seller shall
not contest such geographic scope in any litigation, arbitration or dispute
between Seller and/or its Subsidiaries and the Company or any of its Affiliates)
(i) transmission parts and components for automobiles and light trucks directly
to customers in the Independent Aftermarket (i.e., customers other than vehicle
original equipment manufacturers ("OEMs") and their dealers) or (ii) complete
transmissions for automobiles and light trucks ("Complete Transmissions")
directly to transmission repair specialists in the Independent Aftermarket
("Specialists"); provided, however, that it shall not be considered a violation
of this Section 5.10(a) if, during the Non-Compete Period, (x) Seller or any of
its Subsidiaries acquires, by any means, a company (or all or substantially all
of the assets of a company) with respect to which less than twenty percent (20%)
of its net sales are generated by activities described above and such activities
have completely ceased within one year after such acquisition, (y) Seller or any
of its Subsidiaries sells transmission parts and components in the ordinary
course of providing reverse logistics services for its OEM customers, or
(z) Seller or any of its Subsidiaries sells to Specialists Complete
Transmissions wholly manufactured by Seller or its Subsidiaries; provided that
prior to December 31, 2004 such Complete Transmissions are not marketed or sold
under any name using the letters "ATC", the "Logo" (as hereafter defined), or
any name or mark confusingly similar thereto. As used herein, "reverse
logistics" means the process in which automotive parts and components are sent
by an OEM and/or its dealers to Seller or one of its Subsidiaries, which then
does any of the following with such parts and components: (a) distributes them
to other OEM dealers; (b) sells them, by auction or another method required by
the OEM, to remanufacturers, rebuilders, wholesale distributors, jobbers, core
brokers, Specialists or end users; (c) sells them for scrap; or (d) destroys
them. A transmission will be a Complete Transmission notwithstanding the absence
of a torque converter, transmission fluid filter or other external components. A
Complete Transmission will be deemed to have been "wholly manufactured by Seller
or its Subsidiaries" notwithstanding that the transmission may contain
components manufactured by third Persons."

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    2.  Amendment to Section 7.07.  Section 7.07 of the Stock Purchase Agreement
is hereby amended to read in its entirety as follows:

    "7.07  Use of Name; Logo.  

    (a) Effective as of the Closing hereunder, Seller hereby grants the Company
and the Company Subsidiaries a royalty free, non-exclusive and non-transferable
license to continue to use the logo set forth on Schedule 7.07 (the "Logo")
until December 31, 2004 (the "Transition Date") in any medium (including,
without limitation, catalogs, signs, boxes, invoices and promotional materials).
After the Transition Date the Company and the Company Subsidiaries will not use
the Logo in any manner except that inventory in boxes bearing the Logo as of the
Transition Date may be sold in such boxes after the Transition Date provided
that after the Transition Date the Company shall use commercially reasonable
efforts to cause the Logo on such boxes to be covered over before they are
distributed to customers.

    (b) Except to the extent expressly permitted by the license to be granted
pursuant to Section 7.07(a), from and after the Closing Date the Company and
each Company Subsidiary shall forthwith cease all use, in any medium, that
states or implies that the Company or such Company Subsidiary is an Affiliate of
Seller. Without limiting the generality of the foregoing, the Company shall take
all steps necessary to cause the packaging materials, catalogs and printed
promotional materials containing the Logo that are used by the Company or the
Company Subsidiaries on and after the 30th day after the Closing Date and prior
to the Transition Date, to bear a sticker or other clear notification stating
that the Company and the Company Subsidiaries are not affiliated with Seller.

    (c) The parties agree and acknowledge that use of the Logo by the Company or
any Company Subsidiary after the Transition Date would infringe Seller's
intellectual property rights, and accordingly the Company covenants that it
will, and will cause the Company Subsidiaries to, cease use of the Logo after
the Transition Date.

    (d) On or before March 31, 2004 (i) the Certificate of Incorporation of the
Company and each of its Affiliates shall be amended in order to change its name
to a name that does not contain any direct or indirect reference to Seller or
the letters "ATC" and (ii) the Company shall make appropriate filings reflecting
such name change in each jurisdiction in which the Company or any of such
Affiliates is authorized to conduct business as a foreign corporation.

    3.  No Other Amendment.  Except as provided herein, the Stock Purchase
Agreement is not otherwise modified or amended and remains in force and effect
in accordance with its terms.

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

        ATC DISTRIBUTION GROUP, INC.
 
 
 
 
/s/ ROBERT J. FITZSIMMONS   

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        Name: Robert J. Fitzsimmons         Title: Vice President              
                  AFTERMARKET TECHNOLOGY CORP.
 
 
 
 
/s/ JOSEPH SALAMUNOVICH   

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        Name: Joseph Salamunovich         Title: Vice President

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AMENDMENT NO. 3 TO STOCK PURCHASE AGREEMENT