<PAGE>
        THIRD SUPPLEMENTAL INDENTURE, dated as of May 25, 2000 (the
        "Supplemental Indenture"), among T.O. HAAS TIRE COMPANY, INC.,
        a Nebraska corporation ("Haas Tire"), T.O. HAAS HOLDING CO.,
        INC., a Nebraska corporation ("T.O. Haas Holding") (Haas Tire
        and T.O. Haas Holding collectively referred to as the "New
        Subsidiary Guarantors"), HEAFNER TIRE GROUP, INC. (f/k/a The
        J.H. Heafner Company, Inc.), a Delaware corporation (the
        "Company"), each other existing Subsidiary Guarantor under the
        Indenture referred to below, and FIRST UNION NATIONAL BANK, a
        national banking association, as trustee (the "Trustee") under
        the Indenture referred to below.

                                   WITNESSETH:

         WHEREAS, the Company, the then existing Subsidiary Guarantors and the
Trustee have heretofore executed and delivered an Indenture, dated as of
December 1, 1998, as supplemented by that certain Supplemental Indenture, dated
as of February 22, 1999, as further supplemented by that certain Second
Supplemental Indenture, dated as of May 14, 1999 (as further amended,
supplemented, waived or otherwise modified, collectively, the "Indenture"),
providing for the issuance of an aggregate principal amount of $150 million of
Series D 10% Senior Notes due 2008 of the Company (the "Securities");

         WHEREAS, Section 4.12 of the Indenture provides that the Company is
required to cause each domestic Restricted Subsidiary (other than an Immaterial
Subsidiary that is neither a borrower nor a guarantor under the Credit Facility)
to execute and deliver to the Trustee a Guaranty Agreement pursuant to which
such Restricted Subsidiary will Guarantee payment of the Securities on the same
terms and conditions as those set forth in Article 10 of the Indenture;

         WHEREAS, the Company is causing each of the New Subsidiary Guarantors
to execute this Supplemental Indenture in order to comply with the terms of
Section 4.12 of the Indenture and each of the New Subsidiary Guarantors intends
thereby to become bound as a Subsidiary Guarantor; and

         WHEREAS, pursuant to Section 9.01 of the Indenture, the Trustee, the
existing Subsidiary Guarantors and the Company are authorized to execute and
deliver this Supplemental Indenture amending the Indenture, without the consent
of any Holder (as defined in the Indenture);

         NOW, THEREFORE, in consideration of the foregoing and for other good
and valuable consideration, the receipt of which is hereby acknowledged, the New
Subsidiary Guarantors, the Company, the existing Subsidiary Guarantors and the
Trustee


<PAGE>

mutually covenant and agree for the equal and ratable benefit of the holders of
the Securities as follows:

                                    ARTICLE I

                                   Definitions

         SECTION 1.1       Defined Terms. As used in this Supplemental
Indenture, terms defined in the Indenture or in the preamble or recital hereto
are used herein as therein defined, except that the term "Holders" in this
Supplemental Indenture shall refer to the term "Holders" as defined in the
Indenture and the Trustee acting on behalf or for the benefit of such Holders.
The words "herein," "hereof" and "hereby" and other words of similar import used
in this Supplemental Indenture refer to this Supplemental Indenture as a whole
and not to any particular section hereof.

                                   ARTICLE II

                        Agreement to be Bound; Guarantee

         SECTION 2.1       Agreement to be Bound. Each New Subsidiary Guarantor
hereby becomes a party to the Indenture as a Subsidiary Guarantor and as such
will have all of the rights and be subject to all of the obligations and
agreements of a Subsidiary Guarantor under the Indenture. The New Subsidiary
Guarantors agree to be bound by all of the provisions of the Indenture
applicable to a Subsidiary Guarantor and to perform all of the obligations and
agreements of a Subsidiary Guarantor under the Indenture.

         SECTION 2.2       Guarantee. The New Subsidiary Guarantors hereby
fully, unconditionally and irrevocably guarantee, jointly and severally with
each other Subsidiary Guarantor, to each Holder of the Securities and the
Trustee and its successors and assigns, the full and punctual payment when due,
whether at maturity, by acceleration, by redemption or otherwise and within
applicable grace periods, of the Obligations pursuant to Article 10 of the
Indenture and on the same terms and conditions of the Indenture.

                                   ARTICLE III

                                  Miscellaneous

         SECTION 3.1       Notices. All notices and other communications to the
New Subsidiary Guarantors shall be given as provided in Section 11.02 of the
Indenture.

         SECTION 3.2       Parties. Nothing expressed or mentioned herein is
intended or shall be construed to give any Person, firm or corporation, other
than the Holders and the Trustee, any legal or equitable right, remedy or claim
under or in respect of this Supplemental Indenture or the Indenture or any
provision herein or therein contained.


                                       2
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         Section 3.3       Governing Law. This Supplemental Indenture shall be
governed by the laws of the State of New York, but without giving effect to
applicable principles of conflicts of law to the extent that the application of
the laws of another jurisdiction would be required thereby.

         Section 3.4       Severability Clause. In case any provision in this
Supplemental Indenture shall be invalid, illegal or unenforceable, the validity,
legality and enforceability of the remaining provisions shall not in any way be
affected or impaired thereby and such provision shall be ineffective only to the
extent of such invalidity, illegality or unenforceability.

         Section 3.5       Ratification of Indenture; Supplemental Indenture
Part of Indenture. Except as expressly supplemented hereby, the Indenture is in
all respects ratified and confirmed and all the terms, conditions and provisions
thereof shall remain in full force and effect. This Supplemental Indenture shall
form a part of the Indenture for all purposes, and every Holder of Securities
heretofore or hereafter authenticated and delivered shall be bound hereby. The
Trustee makes no representation or warranty as to the validity or sufficiency of
this Supplemental Indenture.

         Section 3.6       Counterparts. The parties hereto may sign one or more
copies of this Supplemental Indenture in counterparts, all of which together
shall constitute one and the same agreement.

         Section 3.7       Headings. The headings of the Articles and the
sections in this Supplemental Indenture are for convenience of reference only
and shall not be deemed to alter or affect the meaning or interpretation of any
provisions hereof.


                                       3
<PAGE>

         IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed as of the date first above written.

                             HEAFNER TIRE GROUP, INC.


                             By:  /s/ Donald C. Roof
                                  ------------------------------------------
                                  Name: Donald C. Roof
                                  Title: President & Chief Executive Officer


                             T.O. HAAS TIRE GROUP, INC.,
                                  as a New Subsidiary Guarantor


                             By:  /s/ Donald C. Roof
                                  ------------------------------------------
                                  Name: Donald C. Roof
                                  Title: CEO

                             By:  /s/ J. Michael Gaither
                                  ------------------------------------------
                                  Name: J. Michael Gaither
                                  Title: Vice President


                             T.O. HAAS HOLDING CO., INC.,
                                  as a New Subsidiary Guarantor


                             By:  /s/ Donald C. Roof
                                  ------------------------------------------
                                  Name: Donald C. Roof
                                  Title: CEO

                             By:  /s/ J. Michael Gaither
                                  ------------------------------------------
                                  Name: J. Michael Gaither
                                  Title: Vice President


                                       4
<PAGE>

                             CALIFORNIA TIRE COMPANY,
                                  as a Subsidiary Guarantor


                             By:  /s/ Donald C. Roof
                                  ------------------------------------------
                                  Name: Donald C. Roof
                                  Title:Chairman

                             By:  /s/ J. Michael Gaither
                                  ------------------------------------------
                                  Name: J. Michael Gaither
                                  Title: Vice President


                             WINSTON TIRE COMPANY,
                                  as a Subsidiary Guarantor


                             By:  /s/ Donald C. Roof
                                  ------------------------------------------
                                  Name: Donald C. Roof
                                  Title: Chairman

                             By:  /s/ J. Michael Gaither
                                  ------------------------------------------
                                  Name: J. Michael Gaither
                                  Title: Vice President


                             THE SPEED MERCHANT, INC.,
                                  as a Subsidiary Guarantor


                             By:  /s/ Donald C. Roof
                                  ------------------------------------------
                                  Name: Donald C. Roof
                                  Title: Chairman

                             By:  /s/ J. Michael Gaither
                                  ------------------------------------------
                                  Name: J. Michael Gaither
                                  Title: Vice President


                             FIRST UNION NATIONAL BANK,
                                   as Trustee


                             By:  /s/ Shannon Schwartz
                                  ------------------------------------------
                                     Name:  Shannon Schwartz
                                     Title: Vice President


                                       5