<PAGE>
                                                                   EXHIBIT 10.23

                                                                  EXECUTION COPY


                           MASTER AMENDMENT AGREEMENT

                           dated as of April 11, 2002

                                      among

                      APEX TRAILER LEASING & RENTALS, L.P.,
                                    as Lessee

                          WABASH NATIONAL CORPORATION,
                                  as Guarantor

                         WABASH STATUTORY TRUST - 2000,
                                    as Lessor

               STATE STREET BANK AND TRUST COMPANY OF CONNECTICUT,
                              NATIONAL ASSOCIATION,

 not in its individual capacity except as provided herein, but solely as Trustee

                    THE INSTITUTIONS INDICATED IN SCHEDULE I,
                              as Tranche A Lenders

                           FLEET CAPITAL CORPORATION,
                               as Tranche B Lender

                           FLEET CAPITAL CORPORATION,
                              as Owner Participant

                           FLEET CAPITAL CORPORATION,
                               as Collateral Agent

                                       and

                           FLEET CAPITAL CORPORATION,
                             as Administrative Agent
<PAGE>
                                TABLE OF CONTENTS


<TABLE>
<CAPTION>
                                                                              PAGE
                                                                              ----
<S>                                                                           <C>
ARTICLE I      DEFINITIONS; WAIVER..........................................    1

      SECTION 1.1    Use of Defined Terms...................................    1

      SECTION 1.2    Waiver of Rights.......................................    2

ARTICLE II     AMENDMENTS...................................................    2

      SECTION 2.1    Amendments to the Participation Agreement..............    2

            (a)   Amendments to Section 6.1(e)..............................    2

            (b)   Deletion of Section 6.1(f)................................    3

            (c)   Deletion of Section 6.1(g)................................    3

            (d)   Amendments to Section 6.1.................................    3

            (e)   Deletion of Section 2.3(q)................................    4

            (f)   Amendment to Section 10.1(b)..............................    4

            (g)   Amendments to Section 13..................................    5

      SECTION 2.2    Amendments to Appendix A to the Participation
                     Agreement. ............................................    5

            (a)   Amendment to Definition of "Applicable Margin"............    5

            (b)   Addition of Definition of "Bank Group"....................    6

            (c)   Addition of Definition of "Credit Agreement"..............    6

            (d)   Addition of Definition of "Custodian".....................    6

            (e)   Amendment to Definition of "Initial Letter of Credit."....    6

            (f)   Amendment to Definition of "Interest Rate"................    6

            (g)   Amendment to Definition of "Letter of Credit".............    7

            (h)   Amendment to Definition of "Letter of Credit Amount"......    7

            (i)   Amendment to Definition of "Maturity Date"................    7

            (j)   Addition of Definition of "Master Equipment
                  Lease Agreement." ........................................    7

            (k)   Addition of Definition of "Master Equipment
                  Lease Parties." ..........................................    7

            (l)   Addition of Definition of "Noteholder"....................    8

            (m)   Addition of Definition of "Note Purchase Agreement".......    8

            (n)   Addition of the Definition of "Receivables Group."........    8

            (o)   Amendment to Definition of "Receivables Purchase
                  Agreement." ..............................................    8

            (p)   Addition of the Definition of "Reserve Amount"............    8

            (q)   Addition of the Definition of "Restructuring Fee".........    9
</TABLE>


                                      -i-
<PAGE>
                                TABLE OF CONTENTS
                                  (continued)


<TABLE>
<CAPTION>
                                                                              PAGE
                                                                              ----
<S>                                                                           <C>
      SECTION 2.3    Amendments to the Lease................................    9

            (a)   Amendment to Section 1.4..................................    9

            (b)   Deletion of Article VI....................................    9

            (c)   Amendment to Section 9.2(ii) of the Lease.................    9

            (d)   Amendment to Section 13.1 of the Lease....................   10

            (e)   Amendment to Section 17.1 of the Lease....................   10

ARTICLE III    CLOSING CONDITIONS...........................................   11

      SECTION 3.1    Amendment Closing Date.................................   11

      SECTION 3.2    Closing Conditions.....................................   12

            (a)   Amendments to Credit Agreement and Note
                  Purchase Agreements ......................................   12

            (b)   Restructuring Fee.........................................   12

            (c)   Termination and Replacement of Limited Power of
                  Attorney..................................................   12

            (d)   Collateral Estate.........................................   12

            (e)   Representations and Warranties............................   12

            (f)   Closing Proceedings.......................................   12

            (g)   Opinions of Counsel.......................................   13

            (h)   Preliminary Desktop Appraisal.............................   13

            (i)   Establishment of Account for Reserve Amount...............   13

            (j)   Fees and Expenses.........................................   13

ARTICLE IV     MISCELLANEOUS PROVISIONS.....................................   13

      SECTION 4.1    Ratification of and References to the
                     Operative Documents ...................................   13

      SECTION 4.2    Headings, Etc..........................................   13

      SECTION 4.3    Counterparts...........................................   13

      SECTION 4.4    Governing Law; Entire Agreement........................   14

      SECTION 4.5    Instructions to the Trustee............................   14
</TABLE>


                                      -ii-
<PAGE>
                                TABLE OF CONTENTS
                                  (continued)


<TABLE>
<CAPTION>
                                                                                         Page
                                                                                         ----
<S>                                                                                      <C>
SCHEDULE I                    Institutions Participating as Tranche A Lenders
APPENDIX 1 TO SCHEDULE II     Definitions for the purposes of Schedule II
SCHEDULE II                   Financial Covenants
SCHEDULE III                  Excepted Representations and Warranties

EXHIBIT A      Form of Authorized Officer's Certificate of Compliance
EXHIBIT B      Form of Power of Attorney
</TABLE>


                                     -iii-
<PAGE>
                           MASTER AMENDMENT AGREEMENT

      THIS MASTER AMENDMENT AGREEMENT (this "Amendment"), dated as of April 11,
2002, to the Amended and Restated Participation Agreement (the "Participation
Agreement"), dated as of March 30, 2001, and the Amended and Restated Equipment
Lease (the "Lease"), dated as of March 30, 2001, is entered into by and among
APEX TRAILER LEASING & RENTALS, L.P., a Delaware limited partnership, as the
Lessee (in such capacity, together with its permitted successors, the "Lessee");
WABASH NATIONAL CORPORATION, a Delaware corporation, as guarantor (the
"Guarantor"); WABASH STATUTORY TRUST - 2000, a Connecticut statutory trust, as
Lessor (together with its permitted successors and assigns, the "Lessor"); STATE
STREET BANK AND TRUST COMPANY OF CONNECTICUT, NATIONAL ASSOCIATION, not in its
individual capacity, except as set forth herein, but solely as Trustee (the
"Trustee" and in its individual capacity, the "Trust Company"); the Institutions
indicated in Schedule I as "Tranche A Lenders" (each, together with its
permitted successors and assigns, a "Tranche A Lender," and together with the
other Tranche A Lenders, the "Tranche A Lenders"), FLEET CAPITAL CORPORATION, a
Rhode Island corporation ("Fleet Capital"), as the Tranche B Lender (in such
capacity, together with its permitted successors and assigns, the "Tranche B
Lender", and together with the Tranche A Lenders, the "Lenders"); FLEET CAPITAL,
as the Owner Participant (in such capacity, together with its permitted
successors and permitted assigns, the "Owner Participant", and together with the
Lenders, the "Participants"); FLEET CAPITAL, as administrative agent for the
Lenders (in such capacity, together with its permitted successors and assigns,
the "Administrative Agent"); and FLEET CAPITAL, as collateral agent for the
Lenders (in such capacity, together with its permitted successors and assigns,
the "Collateral Agent").

                              W I T N E S S E T H:

      WHEREAS, the Lessee, the Lessor, the Guarantor, the Trustee, the Lenders,
the Owner Participant, the Administrative Agent, and the Collateral Agent have
heretofore entered into a certain Participation Agreement dated March 30, 2001;

      WHEREAS, the Lessee and the Lessor have heretofore entered into a certain
Lease dated as of March 30, 2001;

      WHEREAS, the Lessee, the Lessor, the Guarantor, the Trustee, the Lenders,
the Owner Participant, the Administrative Agent, and the Collateral Agent now
desire to amend the Participation Agreement and the Lessee and Lessor now desire
to amend the Lease.

      NOW, THEREFORE, the parties hereto agree as follows:

                                   ARTICLE I
                               DEFINITIONS; WAIVER

      SECTION 1.1 Use of Defined Terms. Capitalized terms used but not otherwise
defined in this Amendment have the respective meanings specified in Appendix A
to the Participation
<PAGE>
Agreement; and the rules of interpretation set forth in Appendix A to the
Participation Agreement shall apply to this Amendment.

      SECTION 1.2 Waiver of Rights. The Participants, Lessor, Collateral Agent
and Administrative Agent hereby waive their right to declare a Lease Event of
Default under Section 13.1(e) of the Lease arising from a breach by Lessee or
Guarantor of Sections 6.1(e)(ii), (e)(iii), (e)(v) (insofar as such provision
relates to existing Lease Events of Default and not to future Unmatured Lease
Defaults or Lease Events of Default), (f) or (g) of the Participation Agreement
in consideration for the amendments set forth herein.

                                   ARTICLE II
                                   AMENDMENTS

      SECTION 2.1 Amendments to the Participation Agreement.

      (a) Amendments to Section 6.1(e).

      Section 6.1(e) of the Participation Agreement is hereby amended to include
the following provisions after Section 6.1(e)(v):

            (vi) as soon as available and in any event, within thirty (30) days
      after the last day of each calendar month, or within forty five (45) days
      after the last day of each calendar month to the extent such calendar
      month constitutes a quarter end, (x) a copy of Lessee's balance sheet and
      related statements of income, retained income and cash flows, of Lessee
      for such month, setting forth in each case in comparative form the figures
      for the previous month, all in reasonable detail, and certified by the
      chief financial officer, treasurer or corporate controller of Lessee as
      being complete and correct, prepared in accordance with generally accepted
      accounting principles and fairly presenting Lessee's financial condition
      and results of operations; (y) to the extent available, a copy of the
      Guarantor's consolidated balance sheet, and related consolidated
      statements of income, retained income and cash flows, of Guarantor and its
      consolidated subsidiaries for such month, setting forth in each case in
      comparative form the figures for the previous month, all in reasonable
      detail, and certified by the chief financial officer, treasurer or
      corporate controller of Guarantor as being complete and correct, prepared
      in accordance with generally accepted accounting principles and fairly
      presenting Guarantor's financial condition and results of operations; and
      (z) an Authorized Officer's Certificate of each of the Lessee and the
      Guarantor, in each case in the form attached hereto as Exhibit A (with
      appropriate insertions), stating that such Obligor has duly performed and
      complied with all conditions contained in the Financial Covenants attached
      hereto in Schedule II required to be performed or complied with by it;

            (vii) as soon as available and in any event within fifteen (15) days
      after the last day of each calendar month, (x) a copy of all information
      relating to the


                                       2
<PAGE>
      Equipment subject to the Lease and (y) a report indicating the status,
      sale or other disposition of each Unit of Equipment for such month;

            (viii) in the course of each calendar month, all information
      concerning the business or financial condition of the Lessee or the
      Guarantor as is provided to (and at the same time as is provided to) the
      Bank Group, the Receivables Group, the Master Equipment Lease Parties or
      any of the Noteholders; and

            (ix) in the course of each calendar month, all other information as
      is provided to (and at the same time as is provided to) the Bank Group,
      the Receivables Group, the Master Equipment Lease Parties or any of the
      Noteholders.

      (b) Deletion of Section 6.1(f).

      Section 6.1(f) of the Participation Agreement is hereby deleted.

      (c) Deletion of Section 6.1(g).

      Section 6.1(g) of the Participation Agreement is hereby deleted.

      (d) Amendments to Section 6.1.

      Section 6.1 of the Participation Agreement is hereby amended to include
the following additional provisions after Section 6.1(h):

            (i) Inspection. Within thirty (30) days after the Amendment Closing
      Date, each of the Guarantor and the Lessee shall permit, at its sole cost
      and expense, (i) any authorized representative designated by the
      Administrative Agent or any Lender to visit and inspect any of the
      Equipment subject to the Lease, to examine, audit, check and make copies
      of its financial and accounting records, books, journals, orders, receipts
      and any other correspondence and other data relating to its business or
      the transactions contemplated by this Participation Agreement, and to
      discuss their affairs, finance and accounts with their directors,
      officers, employees and certified public accountants, and (ii) the
      Collateral Agent or any of its agents or representatives to conduct a
      comprehensive field audit of its books, records, properties and assets,
      including without limitation the Equipment subject to the Lease, all upon
      reasonable notice, at such reasonable times during normal business hours.

            (j) Reserve Amount. The Reserve Amount shall be maintained until the
      earlier to occur of (i) the Maturity Date, and (ii) the Lien of the
      Collateral Agent against the Collateral Estate having been fully
      discharged in accordance with the terms of the Operative Documents.

            (k) Letter of Credit. Throughout the remaining Term, the Lessee
      shall provide to the Collateral Agent a Letter of Credit in the Letter of
      Credit Amount. The Letter of Credit shall provide that (a) the issuer of
      the Letter of Credit shall,


                                       3
<PAGE>
      at least thirty (30) days prior to the expiration of the Letter of Credit
      (and, in the case of any expiration date scheduled to occur in the twelve
      (12) month period preceding the Termination Date (as defined in the Credit
      Agreement), at least eighty one (81) days prior to such Termination Date),
      provide written notice to the Collateral Agent of the date upon which the
      Letter of Credit is set to expire and whether the Letter of Credit has
      been renewed; and (b) the Collateral Agent may draw upon the Letter of
      Credit in the event of (i) a Lease Event of Default, or (ii) receipt by
      the Collateral Agent of notice from the issuer of the Letter of Credit
      that the Letter of Credit will expire and has not been renewed. During the
      Term, the Lessee shall maintain the Letter of Credit in an amount equal to
      the Letter of Credit Amount and the Letter of Credit shall in all respects
      be in form and substance satisfactory to the Participants. Without
      limiting the Lessor's right to declare a Lease Event of Default and
      exercise its remedies pursuant to Section 13 of the Lease, if the
      Collateral Agent shall draw on the Letter of Credit the proceeds thereof
      shall be immediately applied to the prepayment of the Loans and Equity
      Investments without any further notice or action by the Lessor or the
      Collateral Agent.

            (l) Financial Covenants. The Lessee or Guarantor, as the case may
      be, shall comply in all respects with the financial covenants set forth on
      Schedule II hereto.

            (m) Other Indebtedness. The Lessee and the Guarantor shall not
      amend, modify or supplement, or permit any Subsidiary to amend, modify or
      supplement (or consent to any amendment, modification or supplement of),
      any document, agreement or instrument evidencing the $192,000,000
      aggregate principal amount of the Guarantor's Senior Notes, Series C
      through I, due 2004-2008 (collectively the "Senior Notes"), the NatCity
      Lease Agreement (as defined in the Intercreditor Agreement with respect to
      the Credit Agreement), the Receivables Purchase Agreement, the Note
      Purchase Agreements or the Credit Agreement (or any replacements,
      substitutions or renewals thereof) or pursuant to which any such
      Indebtedness is issued where such amendment, modification or supplement
      provides for the following or which has any of the following effects:

                  (i) increases the overall principal amount of any such
      Indebtedness or increases the amount of any single scheduled installment
      of principal or interest;

                  (ii) shortens or accelerates the date upon which any
      installment of principal or interest becomes due or adds any additional
      mandatory redemption provisions;

                  (iii) shortens the final maturity date of such Indebtedness or
      otherwise accelerates the amortization schedule with respect to such
      Indebtedness;

                  (iv) increases the rate of interest accruing on such
      Indebtedness;


                                       4
<PAGE>
                  (v) provides for the payment of additional fees or increases
      existing fees;

                  (vi) amends or modifies any financial or negative covenant (or
      covenant which prohibits or restricts the Lessee or the Guarantor or a
      Subsidiary of either the Lessee or the Guarantor from taking certain
      actions) in a manner which is more onerous or more restrictive to the
      Lessee or the Guarantor (or any Subsidiary of either of them) or which is
      otherwise materially adverse to the Lessee or the Guarantor and/or the
      Participants or, in the case of adding covenants, which places additional
      restrictions on the Lessee or the Guarantor (or a Subsidiary of either of
      them) or which requires the Lessee or the Guarantor or any such Subsidiary
      to comply with more restrictive covenants than the covenants set forth
      herein or which requires the Lessee or the Guarantor to better its
      financial performance from that set forth in the financial covenants set
      forth herein;

                  (vii) amends, modifies or adds any covenant in a manner which,
      when taken as a whole, is materially adverse to the Lessee or the
      Guarantor and/or the Participants;

                  (viii) amends, modifies or supplements any subordination
      provisions thereof;

                  (ix) amends or modifies the limitations on transfer provided
      therein; or

                  (x) amends or modifies the Collateral Documents (as defined in
      the Credit Agreement) in any manner adverse to the Participants.

      (e) Deletion of Section 2.3(q).

      Section 2.3(q) of the Participation Agreement is hereby deleted.

      (f) Amendment to Section 10.1(b).

      Section 10.1(b) of the Participation Agreement is hereby amended and
restated to read as follows:

            The Lessee shall pay or cause to be paid when due (i) the fees
      described in Section 4.5 and in the Syndication Agreement, (ii) all
      reasonable out-of-pocket expenses of the Trustee, the Administrative Agent
      and the Participants (including reasonable attorneys' fees and legal
      expenses of one special counsel representing the Administrative Agent, the
      Lessor, and the Lenders, under this Participation Agreement and the other
      Operative Documents), (iii) all costs and expenses (including reasonable
      attorneys' fees and legal expenses) incurred by the Administrative Agent,
      the Trustee, or any Participant in entering into any future amendments or
      supplements with respect to any of the Operative Documents, whether or not
      such amendments or supplements are ultimately entered into, or


                                       5
<PAGE>
      giving of waivers of consents hereto or thereto, (iv) all costs and
      expenses (including reasonable attorneys' fees and legal expenses)
      incurred by the Administrative Agent, the Trustee or any Participant in
      connection with any purchase or sale of any part of the Equipment by the
      Lessee or the Lessor, respectively, or any other Person pursuant to the
      Lease, (v) all costs and expenses (including reasonable attorneys' fees
      and legal expenses) incurred by the Administrative Agent, the Trustee or
      any Participant in connection with any substitution, exchange, purchase or
      sale of any Equipment by the Lessee or the Lessor, respectively, or any
      other Person pursuant to the Lease, (vi) all costs and expenses (including
      reasonable attorneys' fees and legal expenses) incurred by any of the
      other parties hereto in respect of (x) the enforcement of any of their
      rights or remedies against the Lessee, or the Guarantor under any of the
      Operative Documents or (y) the negotiation of any restructuring or
      "work-out" with the Lessee, or the Guarantor, whether or not consummated,
      of any obligations of the Lessee, or the Guarantor under the Operative
      Documents (including the Restructuring Fee and costs associated with due
      diligence and perfection with respect to the Collateral Estate), plus any
      default premiums charged by the Participants in connection with such
      restructuring or "work-out" (it being understood that the Participants may
      charge such premium only in the event that a premium has been charged to
      the Guarantor by the Bank Group and/or Noteholders under the Credit
      Agreement and Note Purchase Agreements on the same basis), (vii) all fees
      and expenses (including, without limitation, its attorneys' fees) incurred
      by the Participants in connection with the negotiation and documentation
      of transferring to a third-party Custodian the original certificates of
      title to the Equipment, (viii) all costs and expenses (including
      attorneys' fees and legal expenses) incurred by any Participant, the
      Trustee, the Collateral Agent or the Administrative Agent with respect to
      the establishment and maintenance of the Reserve Amount with the
      Collateral Agent designated by the Participants, (ix) all costs and
      expenses (including reasonable attorneys' fees and legal expenses)
      incurred by any Participant, the Trustee, the Collateral Agent or the
      Administrative Agent with respect to the inspection of the Equipment or
      operations of the Lessee or Guarantor in accordance with Section 6.1(j),
      and (x) all fees, costs and expenses of the Custodian, the Collateral
      Agent and any permitted appraiser.

      (g) Amendments to Section 13.

      Section 13 of the Participation Agreement is hereby amended to include an
additional provision such that the new Section 13.18 will read as follows:

            Appointment of Custodian. The Participants hereby agree to appoint
      Custodian to act for them as the custodian in connection with the transfer
      of physical possession of the original certificates of title for each Unit
      of Equipment subject to the Lease on the transfer date. All costs and
      expenses (including attorneys' fees and legal expenses) incurred by any
      Participant, the Lessor, the Collateral Agent or the Administrative Agent
      with respect to the custodial arrangement required by this Section 13.18
      shall be borne by the Lessee. As soon


                                       6
<PAGE>
      as practicable but in any event within sixty (60) days of the Amendment
      Closing Date, the Lessee shall have transferred to Custodian physical
      possession of the original certificates of title to the Units of Equipment
      then subject to the Lease, in accordance with the terms of Section 9.2(ii)
      of the Lease and shall have entered into a custodial arrangement in form
      and substance satisfactory to the Participants. The Custodian may be
      replaced at any time by the Participants in their sole discretion.

      SECTION 2.2 Amendments to Appendix A to the Participation Agreement.

      (a) Amendment to Definition of "Applicable Margin".

      The definition of "Applicable Margin" in Appendix A to the Participation
Agreement is hereby amended and restated to read as follows:

            "Applicable Margin" means, (a) with respect to the Tranche A and
      Tranche B Eurodollar Loans, 380 basis points per annum, (b) with respect
      to the Eurodollar Equity Investments, 475 basis points per annum, and (c)
      with respect to any Base Rate Loan(s)/Equity Investments, 150 basis points
      per annum.

      (b) Addition of Definition of "Bank Group".

      The following definition of the term "Bank Group" is hereby added to
Appendix A to the Participation Agreement:

            "Bank Group" means Bank One, Indiana, N.A., as administrative agent
      and the institutions from time to time party to the Credit Agreement.

      (c) Addition of Definition of "Credit Agreement".

      The following definition of the term "Credit Agreement" is hereby added to
Appendix A to the Participation Agreement:

            "Credit Agreement" means that certain Credit Agreement dated
      September 30, 1997 among the Guarantor and the Bank Group, as subsequently
      amended or restated.

      (d) Addition of Definition of "Custodian".

      The following definition of the term "Custodian" is hereby added to
Appendix A to the Participation Agreement:

            "Custodian" means the financial institution acting as custodian or
      any other financial institution appointed by the Participants in
      accordance with the terms of Section 13.18 of the Participation Agreement.

      (e) Amendment to Definition of "Initial Letter of Credit."


                                       7
<PAGE>
      The definition of "Initial Letter of Cerdit" in Appendix A to the
Participation Agreement is hereby amended and restated to read as follows:

            "Initial Letter of Credit" means the Irrevocable Standby Letter of
      Credit issued by Bank One, Indiana, N.A. dated December 29, 2000 in the
      original principal amount of $7,770,000, as such amount has been
      subsequently increased to $21,345,000 and the term extended from time to
      time.

      (f) Amendment to Definition of "Interest Rate".

      The definition of "Interest Rate" in Appendix A to the Participation
Agreement is hereby amended and restated to read as follows:

      "Interest Rate" means:

            (a) with respect to Tranche A Loans (i) that are Eurodollar
      Loan(s)/Equity Investments, the Adjusted Eurodollar Rate plus the
      Applicable Margin for such Tranche A Loans and (ii) that are Base Rate
      Loan(s)/Equity Investments, the Base Rate plus the Applicable Margin; and

            (b) with respect to Tranche B Loans (i) that are Eurodollar
      Loan(s)/Equity Investments, the Adjusted Eurodollar Rate plus the
      Applicable Margin for such Tranche B Loans and (ii) that are Base Rate
      Loan(s)/Equity Investments, the Base Rate plus the Applicable Margin.

      (g) Amendment to Definition of "Letter of Credit".

      The definition of "Letter of Credit" in Appendix A to the Participation
Agreement is hereby amended and restated to read as follows:

            "Letter of Credit" means the Initial Letter of Credit as amended and
      extended, or a replacement irrevocable standby letter of credit from a
      bank with a credit rating that is satisfactory to the Lenders, in each
      case in favor of the Collateral Agent in an amount equal to the Letter of
      Credit Amount, and complying with Section 6.1(k) of the Participation
      Agreement.

      (h) Amendment to Definition of "Letter of Credit Amount".

      The definition of "Letter of Credit Amount" in Appendix A to the
Participation Agreement is hereby amended and restated to read as follows:

            "Letter of Credit Amount" means an amount equal to $21,345,000.

      (i) Amendment to Definition of "Maturity Date".

      The definition of "Maturity Date" in Appendix A to the Participation
Agreement is hereby amended and restated to read as follows:


                                       8
<PAGE>
            "Maturity Date" means January 31, 2005.

      (j) Addition of Definition of "Master Equipment Lease Agreement."

      The following definition of the term "Master Equipment Lease Agreement" is
hereby added to Appendix A to the Participation Agreement:

            "Master Equipment Lease Agreement" means that certain Master Lease
      Equipment Agreement as of December 30, 1996 between National City Leasing
      Corporation and Wabash National Finance Corporation.

      (k) Addition of Definition of "Master Equipment Lease Parties."

      The following definition of the term "Master Equipment Lease Parties is
hereby added to Appendix A to the Participation Agreement:

            "Master Equipment Lease Parties" means the parties to the Master
      Equipment Lease Agreement dated as of December 30, 1996.

      (l) Addition of Definition of "Noteholder".

      The following definition of the term "Noteholder" is hereby added to
Appendix A to the Participation Agreement:

            "Noteholder" or "Noteholders" means the Noteholder or Noteholders
      under the Note Purchase Agreements.

      (m) Addition of Definition of "Note Purchase Agreement".

      The following definition of the term "Note Purchase Agreement" is hereby
added to Appendix A to the Participation Agreement:

            "Note Purchase Agreement" or "Note Purchase Agreements" means any of
      those certain Note Purchase Agreements dated as of December 1, 1996 among
      the Guarantor and the Noteholders thereunder as subsequently amended or
      restated.

      (n) Addition of the Definition of "Receivables Group."

      The following definition of the term "Receivables Group" is hereby added
to Appendix A to the Participation Agreement:

            "Receivables Group" means the parties to the Receivables Purchase
      Agreement dated as of April 11, 2002.

      (o) Amendment to Definition of "Receivables Purchase Agreement."

      The following definition of the term "Receivables Purchase Agreement" is
hereby amended and restated to read as follows:


                                       9
<PAGE>
            "Receivables Purchase Agreement" means that certain Receivables
      Purchase Agreement dated as of April 11, 2002 among WNC Receivables, LLC,
      as Seller, Wabash Financing LLC, as Servicer, WNC Receivables Management
      Corporation, as Independent Member, and General Electric Capital
      Corporation, as Initial Purchaser and as Agent (all capitalized terms used
      in this definition having the meaning set forth in such Receivables
      Purchase Agreement).

      (p) Addition of the Definition of "Reserve Amount".

      The following definition of the term "Reserve Amount" is hereby added to
Appendix A to the Participation Agreement:

            "Reserve Amount" means $350,000.00.

      (q) Addition of the Definition of "Restructuring Fee".

      The following definition of the term "Restructuring Fee" is hereby added
to Appendix A to the Participation Agreement:

            "Restructuring Fee" means the fully-earned and non-refundable
      one-time fee paid by the Lessee in consideration for restructuring the
      transactions contemplated in the Participation Agreement, as follows: (a)
      with respect to the Owner Participant, the product of 50 basis points
      times the total amount outstanding on the Equity Investments, and (b) with
      respect to each Lender, the product of 50 basis points times the total
      amount outstanding under its respective Loan.

      SECTION 2.3 Amendments to the Lease.

      (a) Amendment to Section 1.4.

      Section 1.4 of the Lease is hereby amended and restated to read as
follows:

            Renewal Terms. So long as no Unmatured Lease Default or Lease Event
      of Default shall have occurred and be continuing, Lessee may, as provided
      in Section 17.2 hereof, renew this Lease as to all, but not less than all
      of the Units for one or more consecutive one year renewal terms (each
      one-year (or shorter period) term, a "Renewal Term"), provided, however,
      that (i) Lessee only may elect one Renewal Term at a time and (ii)
      notwithstanding anything to the contrary contained herein, Lessee only
      shall be entitled to elect a total of two (2) Renewal Terms after the
      Amendment Closing Date; provided, however, that in any event the
      expiration date of such Renewal Terms shall not end after the Maturity
      Date. The Renewal Term shall commence upon the day following the Initial
      Lease Term Expiration Date or upon the day following the expiration of the
      immediately preceding Renewal Term, as the case may be. The Termination
      Value payable during the Renewal Term in respect of any Unit of Equipment


                                       10
<PAGE>
      suffering an Event of Loss shall be in an amount as determined on Schedule
      I to the applicable Lease Supplements.

      (b) Deletion of Article VI.

      Article VI of the Lease is hereby deleted.

      (c) Amendment to Section 9.2(ii) of the Lease.

      Section 9.2(ii) of the Lease is hereby amended by the addition of the
following provision:

            As soon as practicable but in any event within sixty (60) days after
      the Amendment Closing Date, the Lessee shall transfer possession of the
      original certificates of title and current filings and applications for
      certificates of title, with respect to each Unit of Equipment to the
      Custodian.

      (d) Amendment to Section 13.1 of the Lease.

      Section 13.1 of the Lease is hereby amended to include the addition of the
following Lease Event Default:

            (o) the Lessee shall have failed to comply with its obligations
      under Section 13.18 of the Participation Agreement.

      (e) Amendment to Section 17.1 of the Lease.

      Section 17.1 of the Lease is hereby amended and restated to read as
      follows:

            SECTION 17.1.Early Termination Option for any or all of the
      Equipment.

            (a) At any time during the Term of this Lease, and so long as no
      Lease Event of Default shall have occurred and be continuing hereunder,
      Lessee shall have the option to terminate this Lease with respect to any
      or all of the Equipment. To exercise such option, Lessee shall give Lessor
      an irrevocable written notice of Lessee's intention to terminate this
      Lease with respect to any such Unit or Units of Equipment, which notice
      shall (i) state that Lessee desires to terminate this Lease as to the
      relevant Unit or Units of Equipment and refer specifically to this Section
      17.1, and (ii) specify the date for such termination (which, if all Units
      of Equipment are being terminated, shall be the next Payment Date after
      the date of such notice, but in no event after the Expiration Date, and if
      less than all Units of Equipment are being terminated, the date set forth
      in such notice (in either case, such date, the "Early Termination Date")).
      Upon such election and satisfaction of the terms and conditions set forth
      in this Section 17.1, this Lease shall terminate with respect to any such
      Unit or Units of Equipment on the Early Termination Date. Notwithstanding
      the foregoing, in the event Lessee shall fail to perform its obligations
      in accordance with this Section 17.1, this Lease and each of the
      obligations and duties of Lessee shall continue as if such notice shall
      never have been delivered unless otherwise agreed to by Lessor and


                                       11
<PAGE>
      Lessee shall be responsible for all costs and expenses incurred by Lessor,
      Owner Participant, Collateral Agent, Administrative Agent and any Lenders
      in connection therewith.

            (b) For purposes of this Section 17.1, "Early Termination Payment"
      means an amount equal to (i) the Termination Value of each Unit or all
      Units of Equipment, as the case may be, computed as of the Early
      Termination Date, plus (ii) all Basic Rent then due and owing with respect
      to each such Unit or all Units of Equipment, as the case may be, plus
      (iii) all other Rent due for each such Unit or all Units of Equipment, as
      the case may be, on the Early Termination Date, plus (iv) all accrued and
      unpaid Rent owing for periods prior to the Early Termination Date, plus
      (v) any Break Costs associated with such early termination.

            (c) Upon payment in full of the Early Termination Payment and
      satisfaction of all other conditions set forth herein in connection with a
      termination of this Lease with respect to all of the Equipment pursuant to
      this Section 17.1, Lessor shall convey to Lessee or its designee its title
      thereto pursuant to one or more instruments reasonably satisfactory to the
      parties thereto but subject to the following sentence. Lessor's sale of
      the Equipment hereunder shall be on an as-is, where-is basis, without any
      recourse to, or representation or warranty by, Lessor except as to its
      ownership thereof and the absence of any Lien placed on the Equipment by
      or through Lessor, Owner Participant, any Lender or any successor thereto.
      Lessee shall pay, or reimburse Lessor for the payment of, all applicable
      Taxes imposed as a result of such sale, and all fees, costs and expenses
      of such sale incurred by Lessor, and any other amounts for which, if not
      paid, Lessor will be liable or which, if not paid, would constitute a Lien
      on the Equipment and such obligation shall survive the termination of this
      Lease.

            (d) Upon satisfaction of all other conditions set forth herein in
      connection with a termination of this Lease with respect to some but not
      all of the Equipment (a "Partial Termination"), Lessee may request of the
      Collateral Agent that Custodian promptly provide the certificates of title
      to such Equipment to Lessee; provided that Lessee shall have notified the
      Collateral Agent, Administrative Agent and Custodian by Authorized
      Officer's Certificate of the circumstances of such Partial Termination. On
      the last Business Day of each calendar month, the Lessee shall pay
      directly to the Collateral Agent an amount equal to the Early Termination
      Payment with respect to the Unit or Units of Equipment terminated (as
      specified in the notice provided by the Lessee) in the course of such
      month. The aggregate value of all Units of Equipment terminated in any
      calendar month shall not exceed the Reserve Amount and all Early
      Termination Payments shall be applied to the amounts outstanding under the
      Loans and the Equity Investments in inverse order of maturity. Lessor's
      sale of the Equipment hereunder shall be on an as-is, where-is basis,
      without any recourse to, or representation or warranty by, Lessor except
      as to its ownership thereof and the absence of any Lien placed on the
      Equipment by or through


                                       12
<PAGE>
      Lessor, Owner Participant, any Lender or any successor thereto. Lessee
      shall pay, or reimburse Lessor for the payment of, all applicable Taxes
      imposed as a result of such sale, and all fees, costs and expenses of such
      sale incurred by Lessor, and any other amounts for which, if not paid,
      Lessor will be liable or which, if not paid, would constitute a Lien on
      the Equipment and such obligation shall survive the termination of this
      Lease.

                                  ARTICLE III
                               CLOSING CONDITIONS

      SECTION 3.1 Amendment Closing Date. Subject to the terms and conditions
set forth in this Article III, the amendments described herein shall become
effective on April 11, 2002 at the offices of Sidley Austin Brown & Wood,
Chicago, IL (the "Amendment Closing Date").

      SECTION 3.2 Closing Conditions. The obligation of each of the Participants
to perform its agreements on the Amendment Closing Date shall be subject to the
fulfillment to the reasonable satisfaction of, or the waiver in writing by, the
Participants of the following conditions precedent on or prior to such Amendment
Closing Date:

      (a) Amendments to Credit Agreement and Note Purchase Agreements. On or
before the Amendment Closing Date, the amendments to the Credit Agreement, the
Receivables Purchase Agreement, the Master Equipment Lease Agreement and Note
Purchase Agreements providing for covenants of the Guarantor no more restrictive
than the covenants set forth herein and entered into by the Guarantor with the
Bank Group, the Receivables Group, the Master Equipment Lease Parties and the
Noteholders shall have been duly executed and delivered by the parties thereto
and such amendments shall be in full force and effect and no default shall exist
in the performance by any party of any of its obligations under such agreements.

      (b) Restructuring Fee. On or before the Amendment Closing Date, the Lessee
shall have paid to the Participants the Restructuring Fee and, to the extent
such items have been invoiced, the costs and expenses set forth in Sections
10.1(b)(vi)(y), 10.1(b)(vii), 10.1(b)(viii), 10.1(b)(ix) and 10.1(b)(x) of the
Participation Agreement.

      (c) Termination and Replacement of Limited Power of Attorney. On or before
the Amendment Closing Date, in consideration of the amendments agreed to herein,
the Limited Power of Attorney granted by the Lessor to the Lessee dated as of
December 29, 2000 shall terminate without any further action and in accordance
with its terms and the Lessor shall grant to the Lessee a replacement power of
attorney substantially in the form of Exhibit B hereto, effective during the
period commencing on the Amendment Closing Date and ending sixty (60) days
thereafter.

      (d) Collateral Estate. The interests of the Collateral Agent in and to the
Equipment and the Collateral Estate with respect thereto shall remain secured
for the benefit of the Collateral Agent and protected as against any claims from
the Bank Group, the Receivables


                                       13
<PAGE>
Group, the Master Equipment Lease Parties, the Noteholders, or any other
lenders, creditors or noteholders by the Lessee.

      (e) Representations and Warranties. On the Amendment Closing Date, with
the exception of those disclosed on Schedule III hereto, the representations and
warranties of the Lessee and the Guarantor set forth in the Operative Documents
(or in certificates delivered pursuant thereto) executed by any thereof shall be
true and correct in all respects as though made on and as of such date, except
to the extent such representations or warranties relate solely to an earlier
date, in which case such representations and warranties shall have been true and
correct in all respects on and as of such earlier date.

      (f) Closing Proceedings. All proceedings taken in connection with the
Amendment Closing Date and all documents and instruments to be delivered thereon
or relating thereto shall be reasonably satisfactory to each of the Participants
and its counsel, and each of the Participants and its counsel shall have
received copies of such documents as each of the Participants or its counsel may
reasonably request in connection therewith, all in form and substance reasonably
satisfactory to each of the Participants and its counsel.

      (g) Opinions of Counsel. Each of the Participants, the Lessor, the
Collateral Agent and the Administrative Agent shall have received (i) the
favorable written opinions, in form and scope satisfactory to the Participants,
of counsel to the Lessee and the Guarantor confirming the matters set forth in
the opinions such firm delivered to the Bank Group or the Noteholders under the
Credit Agreement or the Note Purchase Agreements to which the Lessee or the
Guarantor are a party, and (ii) the favorable written opinions dated the
Amendment Closing Date and addressed to each of the Participants, the Lessor,
the Administrative Agent and the Collateral Agent from counsel to the Lessee and
the Guarantor to the effect that this Amendment constitutes the legal, valid and
binding agreement of the Lessee and the Guarantor, is enforceable against the
Lessee and the Guarantor and as to such other matters as the Participants, the
Lessor, the Administrative Agent and the Collateral Agent may require.

      (h) Preliminary Desktop Appraisal. The Collateral Agent shall have been
indemnified in full for the costs and expenses incurred by it in connection with
the preliminary desktop appraisal performed by Taylor & Martin, Inc.

      (i) Establishment of Account for Reserve Amount. On or before the
Amendment Closing Date, the Lessee shall have established an account with the
Collateral Agent and deposited therein an amount equal to the Reserve Amount as
security for the benefit of the Collateral Agent.

      (j) Fees and Expenses. The Lessee shall have paid all the fees, costs and
expenses incurred by Mayer, Brown, Rowe & Maw, as counsel to the Participants,
the Collateral Agent and the Administrative Agent hereunder, in connection with
the execution and delivery of this Amendment.

                                   ARTICLE IV
                            MISCELLANEOUS PROVISIONS


                                       14
<PAGE>
      SECTION 4.1 Ratification of and References to the Operative Documents.
This Amendment shall be deemed to be an amendment to the Participation Agreement
and the Lease and as such agreements are amended hereby, are hereby ratified,
approved and confirmed in each and every respect. All references to any such
Operative Document in any other document, instrument, agreement or writing shall
hereafter be deemed to refer to such Operative Document as amended hereby.

      SECTION 4.2 Headings, Etc. The Table of Contents and headings of the
various Articles, Sections and clauses of this Amendment are for convenience of
reference only and shall not modify, define, expand or limit any of the terms or
provisions hereof.

      SECTION 4.3 Counterparts. This Amendment may be executed by the parties
hereto in separate counterparts, each of which when so executed and delivered
shall be deemed to be an original, but all such counterparts shall together
constitute but one and the same instrument.

      SECTION 4.4 Governing Law; Entire Agreement. THIS AMENDMENT AND EACH OTHER
OPERATIVE DOCUMENT EXECUTED IN CONNECTION HEREWITH SHALL EACH BE DEEMED TO BE A
CONTRACT MADE UNDER AND GOVERNED BY THE LAW OF THE COMMONWEALTH OF MASSACHUSETTS
(EXCLUDING ANY CONFLICT-OF-LAW OR CHOICE-OF-LAW RULES WHICH MIGHT LEAD TO THE
APPLICATION OF THE INTERNAL LAWS OF ANY OTHER JURISDICTION) AS TO ALL MATTERS OF
CONSTRUCTION, VALIDITY AND PERFORMANCE. This Amendment and the other Operative
Documents constitute the entire understanding among the parties hereto with
respect to the subject matter hereof and supersede any prior agreements, written
or oral, with respect thereto.

      SECTION 4.5 Instructions to the Trustee. The undersigned Participants,
Collateral Agent and Administrative Agent hereby authorize and direct the
Trustee to enter into, execute and deliver this Amendment and perform all of the
obligations of the Trustee and Lessor hereunder.


                                       15
<PAGE>
      IN WITNESS WHEREOF, the parties hereto have caused this AMENDMENT to be
executed by their respective officers thereunto duly authorized as of the date
and year first above written.

                                        APEX TRAILER LEASING & RENTALS, L.P.,
                                              as Lessee

                                        By:   Wabash National Corporation,
                                              General Partner


                                              By:_______________________________
                                                    Name:
                                                    Title:


                                        WABASH NATIONAL CORPORATION,
                                              as Guarantor


                                        By:_____________________________________
                                            Name:
                                            Title:

                                        WABASH STATUTORY TRUST - 2000

                                        By:  STATE STREET BANK AND TRUST
                                             COMPANY OF CONNECTICUT, NATIONAL
                                             ASSOCIATION, not in its individual
                                             capacity but solely in its
                                             capacity as Trustee


                                        By:_____________________________________
                                            Name:
                                            Title:


                                       16
<PAGE>
                                        STATE STREET BANK AND TRUST COMPANY OF
                                        CONNECTICUT, NATIONAL ASSOCIATION, not
                                        in its individual capacity, except as
                                        provided herein, but solely as Trustee


                                        By:_____________________________________
                                            Name:
                                            Title:


                                        U.S. BANK, NATIONAL ASSOCIATION
                                        (formerly known as FIRSTAR BANK, N.A.)
                                              as Tranche A Lender


                                        By:_____________________________________
                                            Name:
                                            Title:


                                        GENERAL ELECTRIC CAPITAL CORPORATION,
                                              as Tranche A Lender


                                        By:_____________________________________
                                              Name:
                                              Title:


                                       17
<PAGE>
                                        NATIONAL CITY BANK OF INDIANA,
                                               as Tranche A Lender


                                        By:____________________________________
                                               Name:
                                               Title:


                                        FLEET CAPITAL CORPORATION,
                                              as Tranche B Lender


                                        By:_____________________________________
                                            Name:


                                        FLEET CAPITAL CORPORATION,
                                              as Owner Participant


                                        By:_____________________________________
                                            Name:
                                            Title:


                                        FLEET CAPITAL CORPORATION,
                                              as Administrative Agent


                                        By:_____________________________________
                                            Name:
                                            Title:


                                        FLEET CAPITAL CORPORATION,
                                              as Collateral Agent


                                        By:_____________________________________
                                            Name:
                                            Title:


                                       18
<PAGE>
                                                                      SCHEDULE I
                                                   TO MASTER AMENDMENT AGREEMENT

                 INSTITUTIONS PARTICIPATING AS TRANCHE A LENDERS

TRANCHE A LENDERS:

U.S. Bank, National Association
(formerly known as Firstar Bank, N.A.)
7th & Washington, 7th Floor
St. Louis, MO 63101
Attention: Alan R. Milster
       Vice President
Phone: (314) 418-2468
Fax: (314) 418-2135
E-mail: alan.r.milster@usbank.com

National City Bank of Indiana
One National City Center
Suite 200E
Indianapolis, IN 46255
Attention: Lex Curry
Phone: (317) 267-3668
Fax: (317) 267-8899
Email: lex.curry@national-city.com

General Electrical Capital Corporation
980 Washington Street
Suite 123
Dedham, MA 02026
Attention: Moira Duncan
Phone: 781-467-7007
Fax: 781-407-0183
Email: moira.duncan@gecapital.com


                                       19
<PAGE>
                                                                     SCHEDULE II
                                                   TO MASTER AMENDMENT AGREEMENT

                               FINANCIAL COVENANTS

For purposes of this Schedule II to the Master Amendment Agreement, capitalized
terms used herein and not otherwise defined shall have (a) the meanings set
forth in Appendix 1 to this Schedule II, or (b) to the extent such term is not
defined in such Appendix 1, the meanings set forth in Appendix A to the
Participation Agreement.

Financial Covenants. The Lessee or the Guarantor, as the case may be, shall
comply with the following:

      1.    Minimum Consolidated Tax Adjusted Equity. If the Guarantor shall
            have reported a cumulative tax benefit as of the last day of any
            fiscal quarter specified below, the Guarantor shall, as of the last
            day of such fiscal quarter, maintain Consolidated Tax Adjusted
            Equity at an amount not less than the applicable "Minimum
            Consolidated Tax Adjusted Equity" specified below:

<TABLE>
<CAPTION>
                                               Minimum Consolidated Tax
                      Fiscal Quarter Ending        Adjusted Equity
                      ---------------------    ------------------------
<S>                                            <C>
                      March 31, 2003                $ 99,064,000
                      June 30, 2003                 $100,681,000
                      September 30, 2003            $103,283,000
                      December 31, 2003 and
                      each fiscal quarter
                      thereafter                    $ 96,504,000
</TABLE>

      2.    Minimum Consolidated Equity. If the Guarantor shall not have
            reported a cumulative tax benefit as of the last day of any fiscal
            quarter specified below, the Guarantor shall, as of the last day of
            such fiscal quarter, maintain Consolidated Equity at an amount not
            less than the applicable "Minimum Consolidated Equity" specified
            below:

<TABLE>
<CAPTION>
                                                 Minimum Consolidated
                      Fiscal Quarter Ending             Equity
                      ---------------------      --------------------
<S>                                              <C>
                      March 31, 2003                $87,882,000
                      June 30, 2003                 $90,461,000
                      September 30, 2003            $94,751,000
                      December 31, 2003 and
                      each fiscal quarter
                      thereafter                    $84,077,000
</TABLE>
<PAGE>
      3.    Maximum Leverage Valuation Ratio. The Guarantor shall not permit, as
            of the last day of each of the fiscal quarters specified below, the
            Leverage Valuation Ratio to exceed the applicable "Maximum Leverage
            Valuation Ratio" specified below:

<TABLE>
<CAPTION>
                                                  Maximum Leverage
                     Fiscal Quarter Ending        Valuation Ratio
                     ---------------------        ----------------
<S>                                               <C>
                     June 30, 2002                 0.95 to 1
                     September 30, 2002            0.95 to 1
                     December 31, 2002             0.95 to 1

                     March 31, 2003                0.85 to 1
                     June 30, 2003                 0.80 to 1
                     September 30, 2003            0.80 to 1
                     December 31, 2003 and
                     each fiscal quarter
                     thereafter                    0.75 to 1
</TABLE>

      4.    Minimum Consolidated EBITDA.

            (i) The Guarantor shall, as of the last day of each of the fiscal
            quarters of the Guarantor occurring in calendar year 2002, maintain
            Consolidated EBITDA for the cumulative period commencing on April 1,
            2002 and ending on the last day of such fiscal quarter, at an amount
            not less than $20,000,000.

            (ii) The Guarantor shall, as of the last day of the calendar months
            specified below, maintain Consolidated EBITDA at an amount not less
            than the applicable "Minimum Rolling 12 Month Consolidated EBITDA"
            specified below for the period of 12 consecutive calendar months
            then ending:

<TABLE>
<CAPTION>
                                            Minimum Rolling 12 Month
                     Month Ending             Consolidated EBITDA
                     ------------           ------------------------
<S>                                         <C>
                     January 31, 2003             $36,135,000
                     February 28, 2003            $36,620,000
                     March 31, 2003               $39,301,000
                     April 30, 2003               $40,541,000
                     May 31, 2003                 $41,276,000
                     June 30, 2003                $42,192,000
                     July 31, 2003                $42,877,000
                     August 31, 2003              $43,422,000
                     September 30, 2003           $43,784,000
                     October 31, 2003             $43,941,000
                     November 30, 2003            $43,828,000
                     December 31, 2003            $43,539,000
</TABLE>


                                       2
<PAGE>
<TABLE>
<S>                                               <C>
                     January 31, 2004
                     and each calendar
                     month thereafter             $42,539,000
</TABLE>

      5.    Minimum Interest Coverage Ratio. The Guarantor shall not permit the
            Interest Coverage Ratio as of the last day of each fiscal quarter of
            the Guarantor (commencing with the fiscal quarter ending on or about
            March 31, 2003), for the period of four consecutive fiscal quarters
            then ending, to be less than 1.25 to 1.

      6.    Maximum Capital Expenditures. The Lessee and the Guarantor will not,
            and will not permit any of their respective Subsidiaries to, expend
            for Capital Expenditures during any fiscal year of the Guarantor in
            excess of $6,000,000 in the aggregate for each of the Lessee, the
            Guarantor and such Subsidiaries.

      7.    Maximum Finance Contracts. The Lessee and the Guarantor will not,
            and will not permit any of their respective Subsidiaries to, enter
            into any new Finance Contract if and to the extent that the sum of
            such Finance Contract (a) when added to the aggregate amount of all
            Finance Contracts entered into by the Lessee or the Guarantor or
            such Subsidiaries during the twelve (12) month period that commences
            on the Amendment Closing Date exceeds $5,000,000 or (b) when added
            to the aggregate amount of all Finance Contracts entered into by the
            Lessee or the Guarantor or such Subsidiaries during the twelve (12)
            month period that commences on the first (1st) anniversary of the
            Amendment Closing Date exceeds $5,000,000.


                                       3
<PAGE>
                                                                      APPENDIX 1
                                    TO SCHEDULE II TO MASTER AMENDMENT AGREEMENT

                                   DEFINITIONS

      "AGREEMENT ACCOUNTING PRINCIPLES" means generally accepted accounting
principles as in effect from time to time in the United States, applied in a
manner consistent with those used in preparing the financial statements referred
to in Section 6.1(e) of the Participation Agreement.

      "CAPITAL EXPENDITURES" means, for any period, the aggregate of all
expenditures (whether paid in cash or accrued as liabilities and including
Capitalized Leases and purchase money Indebtedness to the extent permitted
hereunder) by the Lessee, the Guarantor and their Subsidiaries during that
period that, in conformity with Agreement Accounting Principles, are required to
be included in or reflected by the property, plant, equipment or similar fixed
asset accounts reflected in the consolidated balance sheet of the Lessee, the
Guarantor and their Subsidiaries.

      "CAPITALIZED LEASE" of a Person (as defined herein) means any lease of
property by such Person as lessee which would be capitalized on a balance sheet
of such Person prepared in accordance with Agreement Accounting Principles.

      "CAPITALIZED LEASE OBLIGATIONS" of a Person (as defined herein) means the
amount of the obligations of such Person under Capitalized Leases which would be
capitalized on a balance sheet of such Person prepared in accordance with
Agreement Accounting Principles.

      "CASH EQUIVALENTS" means (i) marketable direct obligations issued or
unconditionally guaranteed by the government of the United States; (ii) domestic
and Eurodollar certificates of deposit and time deposits, bankers' acceptances
and floating rate certificates of deposit issued by any commercial bank
organized under the laws of the United States, any state thereof, the District
of Columbia, or its branches or agencies and having capital and surplus in an
aggregate amount not less than $500,000,000 (fully protected against currency
fluctuations for any such deposits with a term of more than ten (10) days);
(iii) shares of money market, mutual or similar funds having net assets in
excess of $500,000,000 maturing or being due or payable in full not more than
one hundred eighty (180) days after the Guarantor's acquisition thereof and the
investments of which are limited to investment grade securities (i.e.,
securities rated at least Baa by Moody's Investors Service, Inc. or at least BBB
by Standard & Poor's Ratings Group) and (iv) commercial paper of United States
banks and bank holding companies and their subsidiaries and United States
finance, commercial, industrial or utility companies which, at the time of
acquisition, are rated A-1 (or better) by Standard & Poor's Ratings Group or P-1
(or better) by Moody's Investors Service, Inc.; provided that the maturities of
such Cash Equivalents shall not exceed 365 days.

      "CONSOLIDATED EBITDA" means, for any period, on a consolidated basis for
the Guarantor and its consolidated Subsidiaries, the sum of the amounts for such
period, without duplication, of (i) Consolidated Operating Income, plus (ii)
charges against income for foreign taxes and U.S. income taxes to the extent
deducted in computing Consolidated Operating
<PAGE>
Income, plus (iii) Interest Expense to the extent deducted in computing
Consolidated Operating Income, plus (iv) depreciation expense to the extent
deducted in computing Consolidated Operating Income, plus (v) amortization
expense, including, without limitation, amortization of goodwill and other
intangible assets to the extent deducted in computing Consolidated Operating
Income, plus (vi) other non-cash charges (in an aggregate amount not in excess
of $15,000,000 during any fiscal year of the Borrower) in accordance with
Agreement Accounting Principles to the extent deducted in computing Consolidated
Operating Income, minus (x) the total interest income of the Borrower and its
Subsidiaries to the extent included in computing Consolidated Operating Income
minus (y) the total tax benefit reported by the Borrower and its Subsidiaries to
the extent included in computing Consolidated Operating Income.

      "CONSOLIDATED EQUITY" means as of the date of any determination thereof,
the total stockholders' equity of the Lessee, the Guarantor and their
Subsidiaries on a consolidated basis, all as determined in accordance with
Agreement Accounting Principles.

      "CONSOLIDATED OPERATING INCOME" means, with reference to any period, the
net operating income (or loss) of the Lessee, the Guarantor and their
Subsidiaries for such period (taken as a cumulative whole on a consolidated
basis) including without limitation all restructuring expenses for such period
(exclusive of "other income/expenses" as reflected in the Guarantor's
consolidated statement of income of the Lessee, the Guarantor and their
Subsidiaries for such period and related to non-operating and non-recurring
income and expenses), as determined in accordance with Agreement Accounting
Principles, after eliminating all offsetting debits and credits between the
Lessee, the Guarantor and their Subsidiaries and all other items required to be
eliminated in the course of the preparation of consolidated financial statements
of the Lessee, the Guarantor and their Subsidiaries in accordance with Agreement
Accounting Principles.

      "CONSOLIDATED TAX ADJUSTED EQUITY" means as of the date of any
determination thereof, Consolidated Equity plus the cumulative federal, state
and local income tax benefit reported by the Guarantor in accordance with
Agreement Accounting Principles.

      "CONSOLIDATED TOTAL ASSETS" means as of the date of any determination
thereof, total assets of the Guarantor and its Subsidiaries determined on a
consolidated basis in accordance with Agreement Accounting Principles.

      "FINANCE CONTRACTS" means any chattel paper originated by the Lessee, the
Guarantor or any of their Subsidiaries pursuant to a bona fide sale in the
ordinary course of business with a customer or any Subsidiary.

      "INDEBTEDNESS" means, with respect to any Person (as defined in this
Appendix A), without duplication,

            (a) its liabilities for borrowed money, including reimbursement
      obligations (contingent or otherwise) with respect to letters of credit;

            (b) its liabilities for the deferred purchase price of property
      acquired by such Person (excluding accounts payable arising in the
      ordinary course of business but


                                       ii
<PAGE>
      including, without limitation, all liabilities created or arising under
      any conditional sale or other title retention agreement with respect to
      any such property);

            (c) its Capitalized Lease Obligations;

            (d) all liabilities for borrowed money secured by any Lien with
      respect to any property owned by such Person (whether or not it has
      assumed or otherwise become liable for such liabilities);

            (e) its Off-Balance Sheet Liabilities (as defined in the Credit
      Agreement);

            (f) its Receivables Facility Attributed Indebtedness; and

            (g) any Contingent Obligation (as defined in the Credit Agreement)of
      such Person with respect to liabilities of a type described in any of
      clauses (a) through (f) hereof.

Indebtedness of any Person shall include all obligations of such Person of the
character described in clauses (a) through (g) to the extent such Person remains
legally liable in respect thereof notwithstanding that any such obligation is
deemed to be extinguished under Agreement Accounting Principles. In no event
shall Indebtedness include Unfunded Liabilities (as defined in the Credit
Agreement) of any Plan of the Guarantor and its Subsidiaries, which amount, as
of December 31, 2001, was zero.

      "INTEREST COVERAGE RATIO" means, as of any date the same is to be
determined, the ratio of (i) Consolidated EBITDA as of such date for (A) in the
case of calculating Consolidated EBITDA for each relevant month in the
Guarantor's fiscal year ending on or about December 31, 2002, the cumulative
period of months ending on and after April 30, 2002 and (B) in the case of
calculating Consolidated EBITDA for each month thereafter, the period of four
consecutive fiscal quarters then ending to (ii) Interest Expense during the same
applicable periods.

      "INTEREST EXPENSE" means, for any period, the total interest expense of
the Lessee, the Guarantor and their consolidated Subsidiaries, whether paid or
accrued (including the total interest expense under a Permitted Receivables
Transfer), including interest expense not payable in cash (including
amortization or write-off of debt discount and debt issuance costs and
commissions and discounts and other fees and charges associated with
Indebtedness (including the Obligations)), all as determined in conformity with
Agreement Accounting Principles.

      "LEVERAGE VALUATION RATIO" means, as of any date the same is to be
determined, the ratio of (i) the sum of the aggregate outstanding principal
amount of the Obligations (excluding L/C Obligations, as such term is defined in
the Credit Agreement) and the Indebtedness under the Note Purchase Agreements to
(ii) Consolidated Total Assets only to the extent consisting of cash and Cash
Equivalents, net inventory, net prepaid and other expenses and net property,
plant and equipment as of such date, in all cases as determined in accordance
with Agreement Accounting Principles.


                                       iii
<PAGE>
      "OBLIGATIONS" means, for purposes of this Schedule II to the Master
Amendment Agreement, all the Loans (as defined in the Credit Agreement),
advances, debts, liabilities, obligations, covenants and duties owing by the
Guarantor to the Administrative Agent (as defined in the Credit Agreement), any
Lender (as defined in the Credit Agreement), the Issuing Lender (as defined in
the Credit Agreement), any Affiliate (as defined in the Credit Agreement) of any
of the foregoing or any Indemnitee (as defined in the Credit Agreement), of any
kind or nature, present or future, arising under the Credit Agreement, the Notes
(as defined in the Credit Agreement), the PIK Notes (as defined in the Credit
Agreement) or any other Loan Document (as defined in the Credit Agreement),
whether or not evidenced by any note, guaranty or other instrument, whether or
not for the payment of money, whether arising by reason of an extension of
credit, loan, guaranty, indemnification, or in any other manner, whether direct
or indirect (including those acquired by assignment), absolute or contingent,
due or to become due, now existing or hereafter arising and however acquired.
The term includes, without limitation, all interest, charges, expenses, fees,
attorneys' fees and disbursements, paralegals' fees (in each case whether or not
allowed), and any other sum chargeable to the Guarantor under the Credit
Agreement or any other Loan Document (as defined in the Credit Agreement).

      "PERMITTED RECEIVABLES TRANSFER" means (i) a sale or other transfer by any
Originator to WNC Receivables, LLC, a Delaware limited liability company and a
wholly-owned Subsidiary of the Guarantor ("WNC") of "Receivables," and
"Collections" under, and as such terms are defined in, the Receivables Sale
Agreement, in accordance with the terms of the Receivables Sale Agreement,
and/or (ii) a sale by WNC to purchasers of "Purchaser Interests" under, and as
such term is defined in, the Receivables Purchase Agreement, in accordance with
the terms of the Receivables Purchase Agreement.

      "PERSON" means, for the purposes of this Schedule II to the Master
Amendment Agreement, any individual, corporation, firm, enterprise, partnership,
trust, incorporated or unincorporated association, joint venture, joint stock
company, limited liability company or other entity of any kind, or any
government or political subdivision or any agency, department or instrumentality
thereof.

      "RECEIVABLES FACILITY ATTRIBUTED INDEBTEDNESS" means the amount of
obligations outstanding under a receivables purchase facility on any date of
determination that would be characterized as principal if such facility were
structured as a secured lending transaction rather than as a purchase.


                                       iv
<PAGE>
                                                                    SCHEDULE III
                                                   TO MASTER AMENDMENT AGREEMENT

                     EXCEPTED REPRESENTATIONS AND WARRANTIES

      The following representation set forth is Section 9.1(e) of the
Participation Agreement is excluded from Section 3.2(e) of the Master Amendment
Agreement:

      Material Adverse Change. There has been no change since September 30,2000
      in the business, Property, financial condition or results of operations of
      the Guarantor and its Subsidiaries which could reasonably be expected to
      have a Material Adverse Effect other than certain restructuring charges to
      be taken in the fourth calendar quarter of 2000 up to $50,000,000 on a
      pre-tax basis.
<PAGE>
                                                                       EXHIBIT A
                                                   TO MASTER AMENDMENT AGREEMENT

                    FORM OF AUTHORIZED OFFICER'S CERTIFICATE
                                  OF COMPLIANCE

To:   The Participants, Lessor and Collateral Agent to the
      Master Amendment Agreement Described Below

            This Compliance Certificate is furnished pursuant to that certain
Master Amendment Agreement dated as of April 11, 2002 (as amended, modified,
renewed or extended from time to time, the "Agreement") among APEX TRAILER
LEASING & RENTALS, L.P., a Delaware limited partnership, as the Lessee (in such
capacity, together with its permitted successors, the "Lessee"); WABASH NATIONAL
CORPORATION, a Delaware corporation, as guarantor (the "Guarantor"); WABASH
STATUTORY TRUST - 2000, a Connecticut statutory trust, as Lessor (together with
its permitted successors and assigns, the "Lessor"); STATE STREET BANK AND TRUST
COMPANY OF CONNECTICUT, NATIONAL ASSOCIATION, not in its individual capacity,
except as set forth therein, but solely as Trustee (the "Trustee" and in its
individual capacity, the "Trust Company"); the Institutions indicated in
Schedule I thereto as "Tranche A Lenders" (each, together with its permitted
successors and assigns, a "Tranche A Lender," and together with the other
Tranche A Lenders, the "Tranche A Lenders"), FLEET CAPITAL CORPORATION, a Rhode
Island corporation ("Fleet Capital"), as the Tranche B Lender (in such capacity,
together with its permitted successors and assigns, the "Tranche B Lender", and
together with the Tranche A Lenders, the "Lenders"); FLEET CAPITAL, as the Owner
Participant (in such capacity, together with its permitted successors and
permitted assigns, the "Owner Participant", and together with the Lenders, the
"Participants"); FLEET CAPITAL, as administrative agent for the Lenders (in such
capacity, together with its permitted successors and assigns, the
"Administrative Agent"); and FLEET CAPITAL, as collateral agent for the Lenders
(in such capacity, together with its permitted successors and assigns, the
"Collateral Agent"). Unless otherwise defined herein, capitalized terms used in
this Compliance Certificate have the meanings ascribed thereto in the Agreement.

      THE UNDERSIGNED HEREBY CERTIFIES THAT:

            1. I am the duly elected ________________ of the [Lessee]
[Guarantor] and the [Chief Financial Officer] [Treasurer];

            2. I have reviewed the terms of the Agreement and I have made, or
have caused to be made under my supervision, a detailed review of the
transactions and conditions of the [Lessee] [Guarantor] and its Subsidiaries
during the accounting period covered by the attached financial statements;

            3. The examinations described in paragraph 2 did not disclose, and I
have no knowledge of, the existence of any condition or event which constitutes
a Lease Event
<PAGE>
of Default or Unmatured Lease Default during or at the end of the accounting
period covered by the attached financial statements or as of the date of this
Certificate, except as set forth below; and

            4. Schedule I and Schedule II attached hereto set forth financial
data and computations evidencing the [Lessee] [Guarantor]'s compliance with
certain covenants of the Agreement and the Excess Cash Flow during the
accounting period covered by the attached financial statements, all of which
data and computations are true, complete and correct.

            Described below are the exceptions, if any, to paragraph 3, listing,
in detail, the nature of the condition or event, the period during which it has
existed and the action which the [Lessee] [Guarantor] has taken, is taking, or
proposes to take with respect to each such condition or event:

________________________________________________________________________________

________________________________________________________________________________


                                       2
<PAGE>
            The foregoing certifications, together with the computations set
forth in Schedule I and Schedule II hereto and the financial statements
delivered with this Certificate in support hereof, are made and delivered this
_____ day of __________, ____.


                                       ________________________________
                                          [Insert Name of Officer]


                                       3
<PAGE>
[Wabash National Corporation] [Apex Trailer Leasing & Rentals, L.P.]
Quarterly Compliance Certificate Worksheet

                             COMPLIANCE CERTIFICATE
          QUARTERLY SCHEDULE OF COMPLIANCE AS OF _______________, 2002
                             (DOLLARS IN THOUSANDS)

<TABLE>
<S>                                                         <C>
A.    EXCESS CASH FLOW
      1.    Actual Amount:
            a.    of Cash & Cash Equivalents                $      --
            a.    Remaining in Super Revolver               $      --
            b.    Remaining in A/R Facility                 $      --
                                                            ---------
            c.    Total Available Liquidity (a+b+c)         $      --

      2.    Projected Amount:
            a.    Liquidity Amount (Sec. 1.1.17)            $      --
            b.    Cash Basket                               $   5,000
                                                            ---------
            c.    Total Projected Liquidity Amount (a+b)    $   5,000

      3.    Cash Flow Available for Debt Paydown (1d - 2c)  $  (5,000)

B.    MAXIMUM LEVERAGE VALUATION RATIO

      1.    Actual Amount:
            a.    Term Debt (Notes & Bank Debt)
            b.    Revolver (Super Revolver)
                                                            ---------
            c.    Total Debt (a+b)                          $      --
            d.    Cash and Cash Equivalents
            e.    Net Inventory
            f.    Net Prepaid and Other Expenses
            g.    Net PP&E
                                                            ---------
            h.    Total Assets (d+e+f+g)                    $      --
            i.    Leveraged Ratio (c/h)                          0.00x

      2.    Minimum Required Amount                                  x

C.    MAXIMUM CAPITAL EXPENDITURES

      1.    Actual Amount:
            a.    Capital Expenditures (Year-to-Date)       $      --

      2.    Maximum Annual Allowed Amount                   $   6,000

D.    MAXIMUM FINANCE CONTRACTS

      1.    Actual Amount:
            a.    Finance Contracts (Year-To-Date)          $      --

      2.    Maximum Annual Allowed Amount                   $   5,000
</TABLE>


                                       4
<PAGE>
[Wabash National Corporation] [Apex Trailer Leasing & Rentals, L.P.]
Monthly Compliance Certificate Worksheet

                             COMPLIANCE CERTIFICATE
              MONTHLY SCHEDULE OF COMPLIANCE AS OF _________, 2003
                             (DOLLARS IN THOUSANDS)

<TABLE>
<S>                                                                           <C>
A.    MINIMUM CONSOLIDATED LAST TWELVE MONTH ("LTM") EBITDA

      1.    Actual Amount:

            a.    Consolidated Operating Income                               $     --
            b.    Foreign and Domestic Taxes Deducted in Operating Income     $     --
            c.    Interest Expense Deducted in Operating Income               $     --
            d.    Other Non-Cash Charges Deducted in Operating Income         $     --
                  (Aggregate Annual Amount not in Excess of $15,000,000)
            e.    Depreciation Expense Deducted in Operating Income           $     --
            f.    Amortization Expense Deducted in Operating Income           $     --
            g.    Interest Income Included in Operating Income                $     --
            h.    Total Tax Benefit Included in Operating Income              $     --
            i.    Consolidated EBITDA (a+b+c+d+e+f-g-h)                       $     --

      2.    Minimum Required Amount                                           $     --
</TABLE>


                                       5
<PAGE>
[Wabash National Corporation] [Apex Trailer Leasing & Rentals, L.P.]
Quarterly Compliance Certificate Worksheet

                             COMPLIANCE CERTIFICATE
             QUARTERLY SCHEDULE OF COMPLIANCE AS OF _________, 2003
                             (DOLLARS IN THOUSANDS)

<TABLE>
<S>                                                         <C>
A.    EXCESS CASH FLOW

      1.    Actual Amount:
            a.    Sum of Cash & Cash Equivalents            $      --
            b.    Availability Remaining in Super Revolver  $      --
            c.    Availability Remaining in A/R Facility    $      --
                                                            ---------
            d.    Total Available Liquidity (a+b+c)         $      --

      2.    Projected Amount:

            a.    Projected Liquidity Amount (Sec. 1.1.17)  $      --
            b.    Additional Cash Basket                    $   5,000
                                                            ---------
            c.    Total Projected Liquidity Amount (a+b)    $   5,000

      3.    Excess Cash Flow Available for Debt
            Paydown (1d - 2c)                               $  (5,000)

B.    MINIMUM TAX ADJUSTED CONSOLIDATED EQUITY

      1.    Actual Amount:

            a.    Consolidated Equity                       $      --
            b.    Deferred Income Taxes                     $      --
                                                            ---------
            c.    Consolidated Tax Adjusted Equity(a-b)     $      --

      2.    Minimum Required Amount                         $      --

C.    MINIMUM CONSOLIDATED EQUITY

      1.    Actual Amount:

            a.    Consolidated Equity                       $      --
            b.    Minimum Required Amount                   $      --

D.    MAXIMUM LEVERAGE VALUATION RATIO

      1.    Actual Amount:
            a.    Term Debt (Notes & Bank Debt)             $      --
            b.    Revolver (Super Revolver)                 $      --
                                                            ---------
            c.    Total Debt (a+b)                          $      --
</TABLE>


                                       6
<PAGE>
<TABLE>
<S>                                                         <C>
            d.    Cash and Cash Equivalents                 $      --
            e.    Net Inventory                             $      --
            f.    Net Prepaid and Other Expenses            $      --
            g.    Net PP&E                                  $      --
                                                            ---------
            h.    Total Assets (d+e+f+g)                    $      --
            i.    Leverage Ratio (c/h)                               x
                                                            ---------
      2.    Minimum Required Amount                                  x
                                                            ---------
E.    MINIMUM INTEREST COVERAGE RATIO

      1.    Actual Amount:
            a.    Cumulative Consolidated Operating Income  $      --
            b.    Cumulative Depreciation Expense           $      --
            c.    Cumulative Amortization Expense           $      --
            d.    Cumulative Consolidated EBITDA (a+b+c)    $      --
            e.    Cumulative Interest Expense               $      --
            f.    Interest Coverage Ratio (d/e)                      x
                                                            ---------
      2.    Minimum Allowed Amount                                 --

F.    MAXIMUM CAPITAL EXPENDITURES

      1.    Actual Amount:
            a. Capital Expenditures (Year-to-Date)          $      --

      2.    Maximum Annual Allowed Amount                   $   6,000

G.    MAXIMUM FINANCE CONTRACTS

      1.    Actual Amount:
            a. Finance Contracts (Year-To-Date)             $      --

      2.    Maximum Annual Allowed Amount                   $   5,000
</TABLE>


                                       7
<PAGE>
<TABLE>
<S>                                                                     <C>
A.    MAXIMUM OTHER UNSECURED INDEBTEDNESS

      1.    Actual Amount                                               $_____________

      2.    Maximum Permitted Amount:                                   $    3,000,000

B.    SALES OF ASSETS

      1.    Actual Amount:

            a.    Total amount of sales of assets in current fiscal
                  year to date (See Schedule II for detail)             $_____________

      2.    Maximum Permitted Amount:                                   $    5,000,000

C.    SALES OF ASSETS BY APEX TRAILER LEASING & RENTALS, L.P. ("APEX")

      1.    Actual Amount:

            a.    Total amount of sales of assets in current
                  fiscal year to date (See Schedule II for detail)      $_____________

      2.    Maximum Permitted Amount:

            a.    Total Assets of APEX at end of prior fiscal year      $_____________

            b.    Intangible assets                                     -_____________

            c.    Tangible Assets of APEX at end of prior
                  fiscal year                                           =$____________

                                                                        x         0.50

            d.    Maximum Permitted Amount                              =$____________

D.    INVESTMENTS

      For each new Investment pursuant to Section 6.3(D)(vii) of the
      Credit Agreement during the most recent fiscal quarter covered
      by this Certificate, complete the following:

      1.    Date and brief description of nature of new Investment:

            ______________________________________________________

            ______________________________________________________

      2.    Actual Amount:

            a.    Amount of new Investment                              $_____________
</TABLE>


                                       8
<PAGE>
<TABLE>
<S>                                                                     <C>
            b.    Amount of existing Investments                        +_____________

            c.    Total Investments                                     =$____________

      3.    Maximum Permitted Amount:                                   $    5,000,000

E.    LEASES

      1.    Actual Amount of Leases:                                    $_____________

      2.    Maximum Permitted Amount:                                   $    5,000,000
</TABLE>


                                       9
<PAGE>
                      SCHEDULE II TO COMPLIANCE CERTIFICATE

                  Schedule of Compliance as of __________, ____

                             (Dollars in Thousands)

<TABLE>
<S>   <C>                                                <C>
A.    Sales of Assets
      [List separate sales and amounts]                  $_____________

                                                          _____________

                                                          _____________

                                                          _____________

                                                          _____________

                                                Total    $_____________
</TABLE>


                                       10
<PAGE>
                                                                       EXHIBIT B
                                                   TO MASTER AMENDMENT AGREEMENT

                            FORM OF POWER OF ATTORNEY

      Reference is made to the Master Amendment Agreement, dated as of April 11,
2002 (the "Master Amendment") among APEX TRAILER LEASING & RENTALS, L.P., a
Delaware limited partnership, as the Lessee (in such capacity, together with its
permitted successors, the "Lessee"); WABASH NATIONAL CORPORATION, a Delaware
corporation, as guarantor (the "Guarantor"); WABASH STATUTORY TRUST - 2000, a
Connecticut statutory trust, as Lessor (together with its permitted successors
and assigns, the "Lessor"); STATE STREET BANK AND TRUST COMPANY OF CONNECTICUT,
NATIONAL ASSOCIATION, not in its individual capacity, except as set forth
therein, but solely as Trustee (the "Trustee" and in its individual capacity,
the "Trust Company"); the Institutions indicated in Schedule I to the Master
Amendment as "Tranche A Lenders" (each, together with its permitted successors
and assigns, a "Tranche A Lender," and together with the other Tranche A
Lenders, the "Tranche A Lenders"), FLEET CAPITAL CORPORATION, a Rhode Island
corporation ("Fleet Capital"), as the Tranche B Lender, in such capacity,
together with its permitted successors and assigns, the "Tranche B Lender", and
together with the Tranche A Lenders, the "Lenders"); FLEET CAPITAL, as the Owner
Participant (in such capacity, together with its permitted successors and
permitted assigns, the "Owner Participant", and together with the Lenders, the
"Participants"); FLEET CAPITAL, as administrative agent for the Lenders (in such
capacity, together with its permitted successors and assigns, the
"Administrative Agent"); and FLEET CAPITAL, as collateral agent for the Lenders
(in such capacity, together with its permitted successors and assigns, the
"Collateral Agent"), and the Amended and Restated Equipment Lease, dated as of
March 30, 2001 (the "Lease") between Lessor and Lessee pursuant to which Lessor
has leased to Lessee certain Units of Equipment described in each Lease
Supplement and consisting of vehicles subject to certificates of title
registered in various states of the United States. Terms not otherwise defined
herein shall have the meanings set forth in either (a) Appendix A to the Amended
and Restated Participation Agreement, dated as of March 30, 2001 (the
"Participation Agreement") among the Lessor, the Lessee, the Trustee, the
Lenders, the Owner Participant, the Collateral Agent and the Administrative
Agent, or (b) the Master Amendment.

      Pursuant to Section 9.2 of the Lease, Lessee is required to deliver to the
Collateral Agent, any and all necessary motor vehicle certificates of title with
lien notations thereon with respect to each Unit of Equipment. In order to
facilitate the sale of the Units of Equipment pursuant to the terms and
conditions of the Lease, Collateral Agent is entering into this Limited Power of
Attorney upon the terms and conditions set forth herein. Notwithstanding
anything to the contrary contained in the Lease, until the earlier to occur of
(i) a Lease Event of Default or (ii) a material adverse change in the business,
financial condition or results of operations of Guarantor and its Subsidiaries
taken as a whole in the reasonable discretion of Collateral Agent, the
undersigned Fleet Capital Corporation, as Collateral Agent hereby grants to the
President, the Treasurer and the Corporate
<PAGE>
Controller from time to time of Wabash National Corporation, solely in its
capacity as the general party of Apex Trailer Leasing & Rentals L.P., as Lessee,
a Limited Power of Attorney to act as agent on behalf of the Lessor and
Collateral Agent regarding procurement of and changes to certificates of title
(including the notation of the lienholder thereon) with respect to the Units of
Equipment in connection with all sales and other dispositions thereof expressly
permitted and in accordance with the provisions of the Lease for a term not to
exceed sixty (60) days after the Amendment Closing Date. Upon the earlier to
occur of (a) the occurrence of an event described in clauses (i) and (ii) above,
and (b) the expiration of the sixty (60) day term of this Limited Power of
Attorney, this Limited Power of Attorney shall immediately cease and Lessee
shall deliver or cause to be delivered to the Custodian each and every original
certificate of title with respect to all Units of Equipment then subject to the
Lease to the address of the Custodian without any further act or deed by
Collateral Agent, Custodian or Lessor.


                                        2
<PAGE>
      IN WITNESS WHEREOF, the undersigned has executed this LIMITED POWER OF
ATTORNEY as of April 11, 2002.

                                    FLEET CAPITAL CORPORATION


                                    By:_________________________________
                                       Name:  Robert E. Merrill
                                       Title:  Vice President

State of Rhode Island   )
                        )  ss.
County of               )

      I certify that I know or have satisfactory evidence that Robert E. Merrill
signed this Limited Power of Attorney and acknowledged it to be his free and
voluntary act and deed for the uses and purposes hereinabove mentioned.

      Dated April __, 2002

                                    _______________________________________
                                    Notary Public for said County and State

                                    My Commission Expires:_________________