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                                                                   EXHIBIT 10.18

                               THIRD AMENDMENT TO
                           LOAN AND SECURITY AGREEMENT

                  THIS THIRD AMENDMENT TO LOAN AND SECURITY AGREEMENT (this
"Amendment"), dated as of August 21, 2003, is entered into by and among Fleet
Capital Corporation, as Administrative Agent (the "Administrative Agent"), Fleet
Capital Canada Corporation, as Canadian Agent (the "Canadian Agent"), the
Lenders and Canadian Participating Lenders party to the Loan Agreement (as
defined below), Celadon Group, Inc., a Delaware corporation ("CGI"), Celadon
Trucking Services, Inc., a New Jersey corporation ("CTSI"), TruckersB2B, Inc., a
Delaware corporation ("TB2B"), and Celadon Canada, Inc., an Ontario corporation
("CCI" and together with CGI, CTSI and TB2B, collectively, the "Borrowers"),
with reference to the following facts:

                                    RECITALS

                  A.       The Administrative Agent, the Canadian Agent, the
Lenders, the Canadian Participating Lenders and the Borrowers are parties to the
Loan and Security Agreement, dated as of September 26, 2002, as amended by the
Waiver and First Amendment to Loan and Security Agreement, dated as of January
31, 2003, and the Waiver and Second Amendment to Loan and Security Agreement,
dated as of April 24, 2003 (collectively, the "Loan Agreement"), pursuant to
which the Lenders have provided the Borrowers with certain credit facilities.

                  B.       CTSI proposes to enter into an Asset Purchase
Agreement, of even date herewith (the "Asset Purchase Agreement"), among CTSI,
Highway Express, Inc., a Virginia corporation (the "Seller"), and J. Harwood
Cochrane, an individual and the sole shareholder of the Seller, pursuant to
which CTSI would purchase from the Seller, and the Seller would sell to CTSI,
substantially all of the assets of the Seller (the "Acquisition").

                  C.       Pursuant to the Asset Purchase Agreement, (i) CTSI
will grant the Seller a security interest in all personal property of CTSI (the
"CTSI-Seller Lien") as collateral security for the payment by CTSI to the Seller
of CTSI's obligation for the deferred portion of the purchase price of the
Acquisition, which deferred payment obligation will be evidenced by a promissory
note issued by CTSI to the Seller (the "CTSI - Seller Note"), and (ii) CGI will
execute an unsecured continuing guaranty in favor of the Seller covering the
obligations of CTSI to the Seller for the payment of interest and principal
under the CTSI - Seller Note (the "CGI - Seller Guaranty").

                  D.       CTSI intends, within one hundred fifty (150) days
after the Acquisition, to sell certain excess or old equipment that it will
acquire from the

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Seller pursuant to the Acquisition and to apply the net proceeds of such sales,
which are estimated to be $3,200,000, to pay down the outstanding principal
balance of the Domestic Term Loan. The Administrative Agent shall re-compute the
principal amortization schedule for the Domestic Term Loan based on the then
outstanding principal balance of the Domestic Term Loan and straight-line
amortization over eighty-four (84) months, and the Borrowers shall execute and
deliver to the Administrative Agent a replacement Term Note for each of the
Domestic Lenders.

                  E.       Pursuant to Section 8.2.1 of the Loan Agreement, CTSI
may not complete the Acquisition without obtaining the prior written consent of
the Majority Lenders; pursuant to Section 8.2.3 of the Loan Agreement, CGI may
not execute the CGI-Seller Guaranty in favor of the Seller without obtaining the
prior written consent of the Majority Lenders; and pursuant to Section 8.2.5 of
the Loan Agreement, CTSI may not grant the CTSI-Seller Lien in favor of the
Seller without obtaining the prior written consent of the Majority Lenders.

                  F.       CTSI and CGI have requested that the Majority Lenders
grant their prior written consent to CTSI's consummation of the Acquisition
(including CTSI's grant of the CTSI-Seller Lien and CGI's issuance of the
CGI-Seller Guaranty in connection with the Acquisition) and that the Domestic
Lenders collectively fund an additional advance in the aggregate principal
amount of $6,000,000 under their respective Domestic Term Loan Commitments to
facilitate CTSI's payment of the portion of the purchase price for the
Acquisition that is payable on the closing date of the Acquisition and the
Borrowers' repayment of a portion of the outstanding principal balance of the
Domestic Revolving Credit Loans.

                  G.       The Majority Lenders and the Domestic Lenders,
respectively, are willing to grant such accommodations to CTSI and CGI on the
terms and conditions set forth below.

                  NOW, THEREFORE, the parties hereby agree as follows:

         1.       Defined Terms. Any and all initially capitalized terms used in
this Amendment (including, without limitation, in the recitals hereto) without
definition shall have the respective meanings specified in the Loan Agreement.

         2.       Consent to Acquisition and Related Transactions. Subject to
the satisfaction of each of the conditions set forth in Section 9 of this
Amendment, the Majority Lenders hereby consent to CTSI's consummation of the
Acquisition and to CTSI's grant of the CTSI-Seller Lien and CGI's issuance of
the CGI-Seller Guaranty in connection with the Acquisition.

         3.       Additional Domestic Term Loan Advances; Repayment of Portion
of Domestic Revolving Credit Loans. The Domestic Lenders agree to make an

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additional term loan to CGI on the effective date of this Amendment in the
aggregate principal amount of $6,000,000 (the "New Domestic Term Loan Advance").
The New Domestic Term Loan Advance shall be combined with the outstanding
principal balance of the Domestic Term Loan on the effective date of this
Amendment. Such combined Loans shall be evidenced by and payable in accordance
with the terms of amended and restated Term Notes (collectively, the "New Term
Notes") in form and substance reasonably satisfactory to the Domestic Lenders,
executed by the Borrowers in favor of the respective Domestic Lenders. Promptly
upon the funding of the New Domestic Term Loan Advance, CTSI shall apply not
less than $2,000,000 of the proceeds of such advance to reduce the outstanding
principal balance of the Domestic Revolving Credit Loans.

         4.       Amendment to Schedule of Lender Commitments. Exhibit 1.1 to
the Loan Agreement is hereby amended to read in full as set forth on Exhibit 1.1
to this Agreement.

         5.       Availability Reserve for Purchased Equipment. On the effective
date of this Amendment, the Administrative Agent shall establish a reserve of
$2,000,000 against borrowing availability under the Domestic Revolving Credit
Loans facility. The Administrative Agent shall obtain a full appraisal of the
motor vehicles and other equipment of the Seller purchased by CTSI pursuant to
the Acquisition, conducted by an independent appraiser selected by the
Administrative Agent, within forty-five (45) days after the effective date of
this Amendment. If, based on such appraisal, the Administrative Agent determines
that the then outstanding principal balance of the New Domestic Term Loan
Advance exceeds ninety percent (90%) of the appraised orderly liquidation value
of the machinery and equipment purchased by CTSI in connection with the
Acquisition (a "Term Loan Overadvance"), the Administrative Agent shall cause a
portion or all of the foregoing availability reserve, in an amount equal to the
Term Loan Overadvance, to remain in effect throughout the term of the Loan
Agreement. If, based on such appraisal, the Administrative Agent determines that
no Term Loan Overadvance exists, the Administrative Agent shall eliminate the
entire $2,000,000 availability reserve.

         6.       Hampton, Virginia Landlord Waiver. Within (30) days after the
effective date of this Amendment, CTSI shall cause the lessor of its
post-Acquisition leased facility in Hampton, Virginia to execute and deliver to
the Administrative Agent a landlord waiver in form and substance acceptable to
the Administrative Agent. If the Administrative Agent does not receive such
landlord waiver by such deadline, the Administrative Agent shall implement a
reserve against availability under the Domestic Revolving Credit Loans facility
in an amount equal to three (3) months rent for such leased facility, which
reserve shall remain in effect until the Administrative Agent receives such
landlord waiver.

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         7.       Fee. In consideration of the agreement of the Administrative
Agent and the Lenders to enter into this Amendment and provide CTSI and CGI with
the accommodations described herein, the Borrowers shall pay to the
Administrative Agent, for its benefit and the benefit of the Lenders, a one-time
fee in the amount of $30,000 (the "Fee"). The Borrowers acknowledge and agree
that the Administrative Agent shall effect payment of the Fee by charging the
full amount thereof to the Borrower's Domestic Revolving Credit Loans account.

         8.       Motor Vehicle Titles. Within forty-five (45) days after the
closing of the Acquisition, CTSI shall file applications with the appropriate
state departments of motor vehicles to indicate the Administrative Agent as the
first lienholder on the certificate of title to each motor vehicle purchased by
CTSI pursuant to the Acquisition other than any excess or old motor vehicles
that CTSI intends to sell in the one hundred fifty (150) day period following
the closing of the Acquisition. CTSI shall send to the Administrative Agent each
week a copy of all such applications filed during the preceding week, together
with a copy of each check issued by CTSI in payment of application fees and any
other related information reasonably requested by the Administrative Agent.

         9.       Conditions Precedent. The effectiveness of this Waiver and
Amendment shall be subject to the prior satisfaction of each of the following
conditions:

                  (a)      This Amendment. The Administrative Agent shall have
                           received this Amendment, duly executed by the
                           Borrowers, the Lenders and the Administrative Agent;

                  (b)      Acquisition Documents. The Administrative Agent shall
                           have received and been satisfied with its review of
                           the final Asset Purchase Agreement and all exhibits
                           and schedules thereto;

                  (c)      Seller Subordination Agreement. The Administrative
                           Agent shall have entered into a subordination
                           agreement with the Seller, in form and substance
                           satisfactory to the Administrative Agent in its sole
                           discretion;

                  (d)      Landlord Waivers. The Administrative Agent shall have
                           received landlord waivers, each in form and substance
                           acceptable to the Administrative Agent, from the
                           respective lessors of the Seller's Richmond, Virginia
                           and Greensboro, North Carolina leased facilities;

                  (e)      The New Term Notes. The Administrative Agent shall
                           have received an original New Term Note for each of
                           the Domestic Lenders, duly executed by the Borrowers;

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                  (f)      Updated Equipment Appraisal. The Administrative Agent
                           shall have received, and been satisfied with its
                           review of, an updated "desktop" appraisal of the
                           motor vehicles and other equipment of the Seller to
                           be purchased by CTSI pursuant to the Acquisition;

                  (g)      The Fee. The Administrative Agent shall have received
                           payment of the Fee; and

                  (h)      Secretary's Certificate. The Secretary of each of the
                           Borrowers shall have executed the Certificate of
                           Resolution attached to this Amendment.

         10.      Miscellaneous.

                  (a)      Survival of Representations and Warranties. All
                           representations and warranties made in the Loan
                           Agreement or in any other document or documents
                           relating thereto, including, without limitation, any
                           Loan Document furnished in connection with this
                           Amendment, shall survive the execution and delivery
                           of this Amendment.

                  (b)      Reference to Loan Agreement. The Loan Agreement, each
                           of the other Loan Documents, and any and all other
                           agreements, documents or instruments now or hereafter
                           executed and delivered pursuant to the terms hereof,
                           or pursuant to the terms of the Loan Agreement as
                           amended hereby, are hereby amended so that any
                           reference therein to the Loan Agreement shall mean a
                           reference to the Loan Agreement as amended by this
                           Amendment.

                  (c)      Loan Agreement Remains in Effect. The Loan Agreement
                           and the other Loan Documents remain in full force and
                           effect and the Borrowers ratify and confirm their
                           agreements and covenants contained therein. The
                           Borrowers hereby confirm that, after giving effect to
                           this Amendment, no Event of Default or Default exists
                           as of such date.

                  (d)      Reaffirmation of Obligations. The Borrowers hereby
                           reaffirm, ratify and confirm their Obligations under
                           the Loan Agreement, acknowledge that they have no
                           offset rights or defenses to the payment of such
                           Obligations, and acknowledge that all of the terms
                           and provisions of the Loan Agreement and the other
                           Loan Documents (except as amended hereby) remain in
                           full force and effect.

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                  (e)      Severability. Any provision of this Amendment held by
                           a court of competent jurisdiction to be invalid or
                           unenforceable shall not impair or invalidate the
                           remainder of this Amendment and the effect thereof
                           shall be confined to the provision so held to be
                           invalid or unenforceable.

                  (f)      Counterparts. This Amendment may be executed in one
                           or more counterparts, each of which when so executed
                           shall be deemed to be an original, but all of which
                           when taken together shall constitute one and the same
                           instrument.

                  (g)      Headings. The headings, captions and arrangements
                           used in this Amendment are for convenience only and
                           shall not affect the interpretation of this
                           Amendment.

                  (h)      Expenses of the Administrative Agent. Borrowers agree
                           to pay on demand all costs and expenses reasonably
                           incurred by the Administrative Agent in connection
                           with the preparation, negotiation and execution of
                           this Amendment and the other Loan Documents executed
                           pursuant hereto, and any and all subsequent
                           amendments, modifications, and supplements hereto or
                           thereto, including, without limitation, the costs and
                           fees of legal counsel to the Administrative Agent.

                  (i)      NO ORAL AGREEMENTS. THIS AMENDMENT, TOGETHER WITH THE
                           OTHER LOAN DOCUMENTS AS WRITTEN, REPRESENTS THE FINAL
                           AGREEMENT BETWEEN THE PARTIES HERETO AND MAY NOT BE
                           CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS OR
                           SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES. THERE ARE
                           NO UNWRITTEN ORAL AGREEMENTS AMONG THE PARTIES
                           HERETO.

                  (j)      GOVERNING LAW; JURY TRIAL WAIVER. THE VALIDITY OF
                           THIS AMENDMENT, ITS CONSTRUCTION, INTERPRETATION AND
                           ENFORCEMENT, AND THE RIGHTS OF THE PARTIES HERETO
                           SHALL BE DETERMINED UNDER, GOVERNED BY AND CONSTRUED
                           IN ACCORDANCE WITH THE INTERNAL LAWS OF THE STATE OF
                           CALIFORNIA, WITHOUT REGARD TO PRINCIPLES OF

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                           CONFLICTS OF LAW. THE PARTIES TO THIS AMENDMENT
                           HEREBY WAIVE THEIR RIGHT TO A TRIAL BY JURY IN ANY
                           ACTION OR PROCEEDING ARISING IN CONNECTION WITH THIS
                           AMENDMENT.

                  IN WITNESS WHEREOF, the parties have entered into this
Amendment by their respective duly authorized officers as of the date first
above written.

                                            CELADON GROUP, INC.,
                                            a Delaware corporation

                                            By: /s/ Paul Will
                                                --------------------
                                                  Paul Will
                                                  Secretary

                                            CELADON TRUCKING SERVICES, INC.,
                                            a New Jersey corporation

                                            By: /s/ Paul Will
                                                --------------------
                                                  Paul Will
                                                  Secretary

                                            TRUCKERSB2B, INC.,
                                            a Delaware corporation

                                            By: /s/ Paul Will
                                                --------------------
                                                  Paul Will
                                                  Secretary

                                            CELADON CANADA, INC.,
                                            an Ontario corporation

                                            By: /s/ Paul Will
                                                --------------------
                                                  Paul Will
                                                  Secretary

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                                         FLEET CAPITAL CORPORATION, a Rhode
                                         Island corporation, as Administrative
                                         Agent and a Lender

                                         By: /s/ Matthew R. Van Steenhuyse
                                             --------------------------------
                                                 Matthew R. Van Steenhuyse
                                                 Senior Vice President

                                         FIFTH THIRD BANK,
                                         as a Lender

                                         By: /s/ David W. O'Neal
                                             -------------------
                                         Name: David W. O'Neal
                                         Title: Vice President

                                         KEYBANK NATIONAL ASSOCIATION,
                                         as a Lender

                                         By: /s/ Michael M. Maher
                                         Name: Michael M. Maher
                                         Title: Senior Vice President

                                         LASALLE BANK NATIONAL ASSOCIATION,
                                         as a Lender

                                         By: /s/ William H. Lutes
                                         Name: William H. Lutes
                                         Title: First Vice President

                                         FLEET CAPITAL CANADA CORPORATION,
                                         as Canadian Agent and Canadian Lender

                                         By: /s/ Doug McKenzie
                                         Name: Doug McKenzie
                                         Title: Vice President & General Manager

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                            CERTIFICATE OF RESOLUTION

         I, Paul Will, hereby certify that:

                                    I am the duly qualified and acting Secretary
of each of Celadon Group, Inc., a Delaware corporation, Celadon Trucking
Services, Inc., a New Jersey corporation, TruckersB2B, Inc., a Delaware
corporation, and Celadon Canada, Inc., an Ontario corporation (collectively, the
"Borrowers").

                                    The following is a true copy of identical
resolutions duly adopted by the respective boards of directors of each of the
Borrowers by either a special meeting or by unanimous written consent in lieu of
a meeting:

                                    "RESOLVED that the terms of the Third
                  Amendment to Loan and Security Agreement among this
                  corporation and the other Borrowers party thereto, the
                  financial institutions which are signatories thereto, Fleet
                  Capital Corporation, as Administrative Agent (the 'Agent'),
                  and Fleet Capital Canada Corporation, as Canadian Agent, are
                  hereby approved and ratified; and

                                    FURTHER RESOLVED, that any one officer of
                  this corporation is hereby authorized and directed, on behalf
                  of this corporation, to make, execute, and deliver to the
                  Agent any and all documents and to do any and all acts
                  necessary or desirable to effectuate the foregoing
                  resolution."

                                    These resolutions are in conformity with the
respective articles or certificate of incorporation and bylaws of the Borrowers,
have never been modified or repealed, and are now in full force and effect.

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                                    IN WITNESS WHEREOF, I have set my hand and
the seal of the corporation as of August 21, 2003.

                                               /s/ Paul Will
                                               -------------
                                               Paul Will
                                               Secretary of Celadon Group, Inc.
                                               Celadon Trucking Services, Inc.,
                                               TruckersB2B, Inc., and
                                               Celadon Canada, Inc.

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