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                                                                   EXHIBIT 10.18

                                 AMENDMENT NO. 3
                         TO LOAN AND SECURITY AGREEMENT

                  THIS AMENDMENT NO. 3 TO LOAN AND SECURITY AGREEMENT
("Amendment") is dated as of December 11, 2003 and is by and among FLEET CAPITAL
CORPORATION, a Rhode Island corporation, and the other parties identified as
Lenders on the signature pages hereto (collectively, "Lenders"), on the one
hand, and WABASH NATIONAL CORPORATION, a Delaware corporation, WABASH NATIONAL,
L.P., a Delaware limited partnership, WNC CLOUD MERGER SUB, INC., an Arkansas
corporation, and FTSI DISTRIBUTION COMPANY, L.P., a Delaware limited partnership
(collectively, "Borrowers"), on the other hand. Capitalized terms used herein
but not otherwise defined herein shall have the respective meanings assigned to
such terms in the Loan Agreement referred to herein below. This Amendment shall
be effective retroactive to November 30, 2003.

                              W I T N E S S E T H:

                  WHEREAS, Lenders and Borrowers are parties to a Loan and
Security Agreement, dated as of September 23, 2003 (as the same has been and may
be amended, or modified from time to time, the "Loan Agreement"), pursuant to
which the Lenders have agreed to make certain loans and other financial
accommodations to or for the account of Borrower;

                  WHEREAS, Borrowers have requested that Lenders amend the Loan
Agreement in certain respects; and

                  WHEREAS, the Majority Lenders have agreed to amend the Loan
Agreement on the terms and subject to the conditions hereinafter set forth;

                  NOW, THEREFORE, in consideration of the premises set forth
above, the terms and conditions contained herein, and other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
respective parties hereto hereby agree as follows:

                  1.       Amendments. Subject to the satisfaction of the
conditions set forth in Section 3 below, and in reliance upon the
representations and warranties of Borrowers set forth herein, the Loan Agreement
is hereby amended as follows:

                  (a)      The parenthetical phrase contained in the fifth
sentence of Section 5.4 of the Loan Agreement shall be deleted and replaced with
the following: "(which surveys shall be delivered on or before January 31,
2004)."

                  (b)      Subsection 6.2.4 of the Loan Agreement is hereby
amended and restated in its entirety, as follows:

                  "Maintenance of Dominion Account. Each Company shall maintain
                  a Dominion Account or Dominion Accounts pursuant to lockbox
                  and blocked

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                  account arrangements acceptable to Agent with Bank and such
                  other banks as may be selected by such Company. Each Company
                  shall obtain the agreement by the applicable banks in favor of
                  Agent to waive any recoupment, setoff rights, and any security
                  interest in, or against, the funds deposited at such banks.
                  Each Company shall issue to any such banks an irrevocable
                  letter of instruction directing (i) such banks located outside
                  Canada to deposit all payments or other remittances received
                  (other than (a) funds in the Excluded Accounts and (b) prior
                  to February 1, 2004, funds in the Legacy Account) to the
                  Dominion Account, (ii) such banks located in Canada to deposit
                  all payments or other remittances received ("Canadian
                  Deposits") to the Dominion Account immediately upon the
                  receipt of notice from Agent that a Dominion Period is in
                  effect and (iii) Bank One, N.A. to deposit all payments or
                  other remittances received in the Legacy Account ("Legacy
                  Deposits") to the Dominion Account upon the earlier to occur
                  of (A) receipt of notice from Agent that a Dominion Period is
                  in effect and (B) February 1, 2004. All funds deposited in the
                  Dominion Account shall be available to Borrowers at their
                  discretion unless a Dominion Period is in effect. Upon the
                  occurrence of a Dominion Event, Agent may, and at the
                  direction of Majority Lenders Agent shall, send the
                  appropriate notice to Borrowers to commence a Dominion Period.
                  If a Dominion Period is in effect, (a) all Canadian Deposits
                  and Legacy Deposits shall immediately become the property of
                  Agent in the ratable benefit of Lenders and shall immediately
                  be deposited to the Dominion Account and (b) all funds in the
                  Dominion Account shall (I) immediately become the property of
                  Agent, for the ratable benefit of Lenders and (II) be applied
                  on account of the Obligations as provided in subsection 3.2.1.
                  Agent shall have the right to invoke three separate Dominion
                  Periods hereunder; once a third Dominion Period has been
                  commenced, it shall remain in effect until the repayment in
                  full of the Obligations. Agent assumes no responsibility for
                  such lockbox and blocked account arrangements, including,
                  without limitation, any claim of accord and satisfaction or
                  release with respect to deposits accepted by any bank
                  thereunder. Notwithstanding anything to the contrary contained
                  herein, all such lockbox and blocked account arrangements will
                  be in place and operational on or before January 31, 2004."

                  (c) Subsection 8.2.1 (iii) of the Loan Agreement is hereby
amended and restated in its entirety, as follows:

                  "(iii) with notice to Agent, dissolution or other termination
                  of existence of any Inactive Subsidiary, any Wind Down
                  Subsidiary, or any of Apex, Continental Transit Corporation,
                  Cloud Oak Flooring Company, Inc., FTSI Distribution Company,
                  L.P., Wabash National Services, L.P., Wabash Technology
                  Corporation and WTSI Technology Corporation; and"

                                       -2-

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                  (d)      Appendix A to the Loan Agreement is hereby amended by
inserting the following definitions therein, in appropriate alphabetical order:

                  Canadian Deposits - as defined in subsection 6.2.4 of the
                  Agreement.

                  Excluded Accounts - those certain Deposit Accounts of Wabash
                  National Services, L.P. at Bank of America, N.A. (account
                  number 3752179833) and WNTC at Bank of America, N.A. (account
                  number 3752180013).

                  Legacy Account - that certain Deposit Account of Wabash at
                  Bank One, N.A. (account number 56900.21).

                  Legacy Deposits - as defined in subsection 6.2.4 of the
                  Agreement.

                  2.       Scope of Amendment. Subject to the satisfaction of
the conditions set forth in Section 3 below and in reliance upon the
representations and warranties of Borrowers set forth therein, this Amendment
shall have the effect of amending the Loan Agreement effective retroactively to
November 30, 2003 as appropriate to express the agreements contained herein. In
all other respects, the Loan Agreement and the other Loan Documents shall remain
in full force and effect in accordance with their respective terms.

                  3.       Conditions to Effectiveness. The effectiveness of
this Amendment and the amendments contained herein are subject to the
satisfaction of the following conditions precedent or concurrent:

                  (a)      Agent shall have received a copy of this Amendment
executed by Borrowers and the Majority Lenders, together with a reaffirmation of
Guaranty Agreement executed by each Guarantor.

                  (b)      No Default or Event of Default shall be in existence.

                  4.       Representations and Warranties. To induce Lenders to
execute and deliver this Amendment, Borrowers hereby represent and warrant to
Lenders that, after giving effect to this Amendment:

                  (a)      All representations and warranties contained in the
Loan Agreement and the other Loan Documents are true and correct in all material
respects on and as of the date of this Amendment, in each case as if then made,
other than representations and warranties that expressly relate solely to an
earlier date (in which case such representations and warranties remain true and
accurate on and as of such earlier date).

                  (b)      No Default or Event of Default has occurred which is
continuing.

                  (c)      This Amendment, and the Loan Agreement, as amended
hereby, constitute legal, valid and binding obligations of Borrowers and are
enforceable against Borrowers in accordance with their respective terms.

                                       -3-

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                  (d)      The execution and delivery by Borrowers of this
Amendment does not require the consent or approval of any Person, except such
consents and approvals as have been obtained.

                  5.       Governing Law. THE VALIDITY, INTERPRETATION AND
ENFORCEMENT OF THIS AMENDMENT SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE
WITH, THE INTERNAL LAWS AND DECISIONS OF THE STATE OF ILLINOIS, WITHOUT REGARD
TO CONFLICT OF LAWS PRINCIPLES.

                  6.       Headings. Section headings in this Amendment are
included herein for convenience of reference only and shall not constitute a
part of this Amendment for any other purpose.

                  7.       Counterparts. This Amendment may be executed in any
number of counterparts and by the different parties hereto in separate
counterparts, each of which when so executed and delivered shall be an original,
but all of which shall together constitute one and the same instrument. Any such
counterpart which may be delivered by facsimile transmission shall be deemed the
equivalent of an originally signed counterpart and shall be fully admissible in
any enforcement proceedings regarding this Amendment.

                           [SIGNATURE PAGES TO FOLLOW]

                                       -4-

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

                                    LENDERS:

                                    FLEET CAPITAL CORPORATION, as Lender

                                    By: /s/
                                        ----------------------------------------
                                    Title: Sr. Vice President

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                                    NATIONAL CITY COMMERCIAL
                                     FINANCE, INC., as Lender

                                    By: /s/
                                        ----------------------------------------
                                    Title: Vice President

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                                    GENERAL ELECTRIC
                                     CAPITAL CORPORATION, as Lender

                                    By: /s/
                                        ----------------------------------------
                                    Title: Vice President

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                                    WACHOVIA BANK,
                                     NATIONAL ASSOCIATION, as Lender

                                    By: /s/
                                        ----------------------------------------
                                    Title: VP

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                                    MERRILL LYNCH CAPITAL, a Division of
                                     Merrill Lynch Business Financial Services,
                                     Inc., as Lender

                                    By: /s/
                                        ----------------------------------------
                                    Title: VP

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                                    WASHINGTON MUTUAL BANK, as Lender

                                    By: /s/
                                        ----------------------------------------
                                    Title: Vice President

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                                    FIFTH THIRD BANK, as Lender

                                    By: /s/
                                        ----------------------------------------
                                    Title: Vice President

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                                    LASALLE BANK NATIONAL ASSOCIATION,
                                    as Lender

                                    By: /s/
                                        ----------------------------------------
                                    Title: FVP

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                                    BORROWERS:

                                    WABASH NATIONAL CORPORATION

                                    By /s/
                                       -----------------------------------------
                                    Title: Vice President & Treasurer

                                    WABASH NATIONAL, L.P.

                                    By /s/
                                       -----------------------------------------
                                    Title: Authorized Representative

                                    WNC CLOUD MERGER SUB, INC.

                                    By /s/
                                       -----------------------------------------
                                    Title: Authorized Representative

                                    FTSI DISTRIBUTION COMPANY, L.P.

                                    By /s/
                                       -----------------------------------------
                                    Title: Authorized Representative

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                                  REAFFIRMATION

                  Wabash National Trailer Centers, Inc., a Delaware corporation,
Wabash Financing LLC, a Delaware limited liability company, National Trailer
Funding, L.L.C., a Delaware limited liability company, Apex Trailer Leasing &
Rentals, L.P., a Delaware limited partnership, Continental Transit Corporation,
an Indiana corporation, WTSI Technology Corp., a Delaware corporation, Wabash
Technology Corp., a Delaware corporation, and Wabash National Services, L.P., a
Delaware limited partnership, (each "Guarantor" and collectively, "Guarantors")
hereby (i) acknowledge receipt of a copy of the foregoing Amendment No. 3 to
Loan and Security Agreement (the "Amendment"); (ii) affirm that nothing
contained in the Amendment shall modify in any respect whatsoever any Loan
Document to which any Guarantor is a party; and (iii) reaffirm that such Loan
Documents and all obligations of the Guarantors thereunder shall continue to
remain in full force and effect.

                  IN WITNESS WHEREOF, Guarantors have executed this
Reaffirmation on and as of the date of the Amendment.

                                    WABASH NATIONAL TRAILER CENTERS, INC.

                                    By /s/
                                       -----------------------------------------
                                    Title Authorized Representative

                                    WABASH FINANCING LLC

                                    By /s/
                                       -----------------------------------------
                                    Title Authorized Representative

                                    NATIONAL TRAILER FINANCING, L.L.C.

                                    By /s/
                                       -----------------------------------------
                                    Title Authorized Representative

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                                    APEX TRAILER LEASING & RENTALS, L.P.

                                    By /s/
                                       -----------------------------------------
                                    Title Authorized Representative

                                    CONTINENTAL TRANSIT CORPORATION

                                    By /s/
                                       -----------------------------------------
                                    Title Authorized Representative

                                    WTSI TECHNOLOGY CORP.

                                    By /s/
                                       -----------------------------------------
                                    Title Authorized Representative

                                    WABASH TECHNOLOGY CORP.

                                    By /s/
                                       -----------------------------------------
                                    Title Authorized Representative

                                    WABASH NATIONAL SERVICES, L.P.

                                    By /s/
                                       -----------------------------------------
                                    Title Authorized Representative