<PAGE>
                           WAIVER AND AMENDMENT NO. 4
                         TO LOAN AND SECURITY AGREEMENT

                  THIS WAIVER AND AMENDMENT NO. 4 TO LOAN AND SECURITY AGREEMENT
("Amendment") is dated as of September 29, 2004 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.

                              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 (i) waive the
requirement that certain appraisals be delivered during the 2004 fiscal year as
required under Section 2.10 of the Loan Agreement and (ii) amend the Loan
Agreement in certain respects; and

                  WHEREAS, Lenders have agreed to do so 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. Waiver. Subject to the satisfaction of the conditions set
forth in Section 4 below, and in reliance on the representations set forth in
Section 5 below, Agent and Lenders hereby waive the requirement set forth in
Section 2.10 of the Loan Agreement that certain appraisals of Inventory, Bill
and Hold Inventory and Trailer Inventory be obtained during the 2004 fiscal
year. This is a limited waiver and shall not be deemed to constitute a waiver
of, or consent to, any current or future breach of the Loan Agreement or any of
the other Loan Documents or any other requirements of any provision of the Loan
Agreement or any other Loan Documents.

                  2. Amendments. Subject to the satisfaction of the conditions
set forth in Section 4 below, and in reliance upon the representations and
warranties set forth in Section 5 below, the Loan Agreement is hereby amended as
follows:

<PAGE>
                  (a) Section 2.10 of the Loan Agreement is hereby amended and
restated in its entirety, as follows:

                  "2.10    Collateral Protection Expenses; Appraisals.

                           All commercially reasonable out-of-pocket expenses
                  incurred in protecting, storing, warehousing, insuring,
                  handling, maintaining and shipping the Collateral, and any and
                  all excise, property, sales, and use taxes imposed by any
                  state, federal, or local authority on any of the Collateral or
                  in respect of the sale thereof shall be jointly and severally
                  borne and paid by Borrowers. If Borrowers fail to promptly pay
                  any portion thereof when due, Agent may, at its option, but
                  shall not be required to, pay the same and charge one or more
                  Borrowers therefor. On an annual basis commencing on January
                  1, 2005, at Borrowers' joint and several expense, (i) as
                  requested by Agent or Majority Lenders in their reasonable
                  credit judgment or (ii) promptly after any period of 10
                  consecutive days during which Availability is less than
                  $30,000,000 Agent shall (A) obtain a desk top appraisal of the
                  Inventory, the Bill and Hold Inventory and the Trailer
                  Inventory of the Companies conducted by an employee of Agent
                  or a third party appraiser reasonably acceptable to Agent and
                  (B) obtain an appraisal of the Inventory, the Bill and Hold
                  Inventory and the Trailer Inventory of the Companies from a
                  third party appraiser reasonably acceptable to Agent, each of
                  which appraisals shall include an assessment of the net
                  orderly liquidation percentage of each category or type of
                  Inventory, Bill and Hold Inventory and Trailer Inventory.
                  Additionally, from time to time, if Agent or any Lender
                  determines that obtaining appraisals is necessary in order for
                  it to comply with applicable laws or regulations, and at any
                  time if a Default or an Event of Default shall have occurred
                  and be continuing, Agent may, and at the direction of the
                  applicable Lender, Agent shall, at Borrowers' joint and
                  several expense, obtain appraisals from appraisers (who may be
                  personnel of Agent), stating the then current fair market
                  value of all or any portion of the real Property or personal
                  Property of any Company, including without limitation the
                  Inventory of any Company."

                  (b) Subsection 3.3.2 of the Loan Agreement is hereby amended
and restated in its entirety, as follows:

                  "3.3.2 [INTENTIONALLY OMITTED]"

                  (c) Subsection 8.1.4 of the Loan Agreement is hereby amended
and restated in its entirety, as follows:

                  "Borrowing Base Certificates. On or before the 20th day after
                  each fiscal quarter from and after the date hereof, Borrowers
                  shall deliver to Agent, in form acceptable to Agent, a
                  Borrowing Base Certificate as of the last day of the
                  immediately preceding fiscal quarter, with such supporting
                  materials as Agent shall reasonably request. On or before the
                  20th day after each month


                                      -2-
<PAGE>
                  from and after the date hereof (other than a month that is the
                  end of a fiscal quarter), Borrowers shall deliver to Agent, in
                  form and acceptable to Agent, an interim Borrowing Base
                  Certificate as of the last day of the immediately preceding
                  month calculated in a manner acceptable to Agent; provided,
                  that if Availability is less than $30,000,000 for any period
                  of 10 consecutive days, Borrowers shall deliver a fully
                  updated Borrowing Base Certificate for the month ending
                  subsequent to the last day of such period. If (a) Borrowers
                  deem it advisable, (b) Agent so requests in its reasonable
                  discretion or (c) Availability is less than $15,000,000,
                  Borrowers shall execute and deliver to Agent Borrowing Base
                  Certificates updating on a weekly basis Eligible Accounts
                  information, Eligible Inventory information relating to
                  finished goods and work-in process, Eligible Trailer Inventory
                  information and Eligible Bill and Hold Inventory information.
                  All Borrowing Base Certificates shall reflect all information
                  for each Borrower on a Consolidated and consolidating basis."

                  (d) Subsection 8.2.8 of the Loan Agreement is hereby amended
and restated in its entirety, as follows:

                  "8.2.8 Capital Expenditures. Make Capital Expenditures
                  (including, without limitation, by way of capitalized leases)
                  which, in the aggregate, as to all Borrowers and all of
                  Borrowers' Subsidiaries, exceed (i) $10,000,000 during the
                  fiscal year ending December 31, 2003, (ii) $10,000,000 during
                  the fiscal year ending December 31, 2004, (iii) $20,000,000
                  during the fiscal year ending December 31, 2005 or (iv)
                  $15,000,000 during any subsequent fiscal year, except that 50%
                  of the unused portion of the Capital Expenditure allowance for
                  any fiscal year may be carried over to the immediately
                  succeeding fiscal year only, to be used in such succeeding
                  fiscal year after all of the Capital Expenditure allowance for
                  that year has been used."

                  (e) Appendix A to the Loan Agreement is hereby amended as
follows:

                  (i)      the definition of "Applicable Margin" is hereby
                           hereby amended and restated in its entirety, as
                           follows:

                  "Applicable Margin - from September ___, 2004 to, but not
         including, the first Adjustment Date (as hereinafter defined) the
         percentages set forth below with respect to the Base Rate Revolving
         Portion, the Base Rate Term Portion, the LIBOR Revolving Portion, the
         LIBOR Term Portion and the Unused Line Fee:

                   Base Rate Revolving Portion           0.25%
                   Base Rate Term Portion                0.25%
                   LIBOR Revolving Portion               2.25%
                   LIBOR Term Portion                    2.25%
                   Unused Line Fee                       0.375%



                                      -3-
<PAGE>
                  The percentages set forth above will be adjusted 3 days
         following delivery by Borrowers to Agent of the financial statements
         required to be delivered pursuant to subsection 8.1.3(ii) of the
         Agreement for each March 31, June 30, September 30 and December 31
         during the Term, commencing with the financial statements required to
         be delivered for the month ending September 30, 2004 (each such date,
         an "Adjustment Date"), effective prospectively on the first day of the
         month immediately following such delivery, by reference to the
         applicable "Financial Measurement" (as defined below) for the four
         quarters most recently ending in accordance with the following:
<Table>
<Caption>
         ----------------------------------- -------------- ------------- -------------- ------------- --------------
                                              Base Rate      Base Rate       LIBOR       LIBOR Term    Unused Line
                                              ----------     ----------      ------      -----------   -----------
               Financial Measurement          Revolving     Term Portion   Revolving       Portion          Fee
               ---------------------          ----------    ------------   ----------      -------          ---
                                                Portion                      Portion
                                                -------                      -------
         ----------------------------------- -------------- ------------- -------------- ------------- --------------
         <S>                                  <C>            <C>          <C>            <C>            <C>
         Less than 1.75 to 1.00                  0.25%         0.25%          2.25%         2.25%         0.375%
         ----------------------------------- -------------- ------------- -------------- ------------- --------------
         Greater than or equal to 1.75 to        0.00%         0.00%          2.00%         2.00%         0.375%
         1.00 and less than 2.50 to 1.00
         ----------------------------------- -------------- ------------- -------------- ------------- --------------
         Greater than or equal to                0.00%         0.00%          1.75%         1.75%         0.250%
         2.50 to 1.00
         ----------------------------------- -------------- ------------- -------------- ------------- --------------
</Table>
         provided that, (i) if Borrowers' audited financial statements for any
         fiscal year delivered pursuant to subsection 8.1.3(i) of the Agreement
         reflect a Financial Measurement that yields a higher Applicable Margin
         than that yielded by the monthly financial statements previously
         delivered pursuant to subsection 8.1.3(ii) of the Agreement for the
         last month of such fiscal year, the Applicable Margin shall be
         readjusted retroactively for the period that was incorrectly
         calculated, (ii) if Borrowers fail to deliver the financial statements
         required to be delivered pursuant to subsection 8.1.3(i) or subsection
         8.1.3(ii) of the Agreement on or before the due date thereof, the
         Applicable Margin shall automatically adjust to the highest pricing
         tier set forth above, effective prospectively from such due date until
         the next Adjustment Date and (iii) if on any Adjustment Date an Event
         of Default is in existence, the Applicable Margin shall not be lowered
         regardless of the Financial Measurement on such Adjustment Date. For
         purposes hereof, "Financial Measurement" shall mean the Fixed Charge
         Coverage Ratio."

                  (ii)     The definition of "Excess Cash Flow" is hereby
                           deleted in its entirety.

                  3. Scope of Amendment. Subject to the satisfaction of the
conditions set forth in Section 4 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 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.



                                      -4-
<PAGE>
                  4. 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 Lenders, together with a reaffirmation of Guaranty
Agreement executed by each Guarantor; and

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

                  5. 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.

                  (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.

                  6. 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.

                  7. 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.

                  8. 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.



                                      -5-
<PAGE>



                           [SIGNATURE PAGES TO FOLLOW]



































                                      -6-
<PAGE>



                  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 Agent
                                      and as a Lender


                                      By: /s/ Christopher M. Wolf
                                         ---------------------------------

                                      Title: V.P.
                                            ------------------------------


<PAGE>



                                      NATIONAL CITY COMMERCIAL
                                      FINANCE, INC., as Syndication Agent and
                                      as a Lender


                                      By: /s/ Katheryn C. Ellero
                                         ---------------------------------

                                      Title: V.P.
                                            ------------------------------


<PAGE>


                                      GENERAL ELECTRIC
                                      CAPITAL CORPORATION, as a Documentation
                                      Agent and as a Lender


                                      By: /s/ Dwayne L. Coker
                                         ---------------------------------

                                      Title: Duly Authorized Signatory
                                            ------------------------------


<PAGE>


                                      WACHOVIA BANK,
                                      NATIONAL ASSOCIATION, as a
                                      Documentation Agent and as a Lender


                                      By: /s/ Monica N. Cole
                                         ---------------------------------

                                      Title: V.P.
                                            ------------------------------


<PAGE>


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


                                      By: /s/ Richard Holston
                                         ---------------------------------

                                      Title: V.P.
                                            ------------------------------


<PAGE>


                                      WASHINGTON MUTUAL BANK, as a Lender


                                      By: /s/ Deborah Saffie
                                         ---------------------------------

                                      Title: V.P.
                                            ------------------------------


<PAGE>


                                      FIFTH THIRD BANK, as a Lender


                                      By: /s/ Steven Kuhn
                                         ---------------------------------

                                      Title: V.P.
                                            ------------------------------


<PAGE>


                                      LASALLE BANK NATIONAL ASSOCIATION,
                                      as a Lender


                                      By: /s/ Andrew J. Crask
                                         ---------------------------------

                                      Title: A.V.P.
                                            ------------------------------


<PAGE>


                                      BORROWERS:

                                      WABASH NATIONAL CORPORATION


                                      By:   c/o Robert J. Smith
                                         -----------------------------------
                                      Title:  Vice President and Controller
                                            --------------------------------


                                      WABASH NATIONAL, L.P.


                                      By:   c/o Robert J. Smith
                                         -----------------------------------
                                      Title: Vice President and Controller
                                            --------------------------------


                                      WNC CLOUD MERGER SUB, INC.


                                      By:   c/o Robert J. Smith
                                         -----------------------------------
                                      Title: Vice President and Controller
                                            --------------------------------


                                      FTSI DISTRIBUTION COMPANY, L.P.


                                      By:   c/o Robert J. Smith
                                         -----------------------------------
                                      Title: Vice President and Controller
                                            --------------------------------



<PAGE>

                                  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, Wabash National Services, L.P., a Delaware limited
partnership, and Cloud Oak Flooring Company, Inc., an Arkansas corporation (each
"Guarantor" and collectively, "Guarantors"), hereby (i) acknowledge receipt of a
copy of the foregoing Waiver and Amendment No. 4 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:    c/o Robert J. Smith
                                        -----------------------------------
                                     Title: Vice President and Controller
                                           --------------------------------

                                     WABASH FINANCING LLC


                                     By:    c/o Robert J. Smith
                                        -----------------------------------
                                     Title: Vice President and Controller
                                           --------------------------------

                                     NATIONAL TRAILER FUNDING, L.L.C.


                                     By:    c/o Robert J. Smith
                                        -----------------------------------
                                     Title: Vice President and Controller
                                           --------------------------------

                                     APEX TRAILER LEASING & RENTALS, L.P.


                                     By:    c/o Robert J. Smith
                                        -----------------------------------
                                     Title: Vice President and Controller
                                           --------------------------------


<PAGE>

                                     CONTINENTAL TRANSIT CORPORATION


                                     By:    c/o Robert J. Smith
                                        -----------------------------------
                                     Title: Vice President and Controller
                                           --------------------------------

                                     WABASH NATIONAL SERVICES, L.P.


                                     By:    c/o Robert J. Smith
                                        -----------------------------------
                                     Title: Vice President and Controller
                                           --------------------------------

                                     CLOUD OAK FLOORING COMPANY, INC.


                                     By:    c/o Robert J. Smith
                                        -----------------------------------
                                     Title: Vice President and Controller
                                           --------------------------------