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                                                                     Exhibit 4.4

                             AMENDMENT NO. 3 TO THE
                         POOLING AND SERVICING AGREEMENT

     THIS AMENDMENT NO. 3 (this "Amendment") is made as of July 17, 1998, by and
among Navistar Financial Securities Corporation, a Delaware corporation
("NFSC"), Navistar Financial Corporation, a Delaware corporation ("NFC"), and
The Bank of New York, as Master Trust Trustee (the "Master Trust Trustee").

     NFSC, as Seller, NFC, as Servicer, The Chase Manhattan Bank (formerly known
as Chemical Bank), as 1990 Trust Trustee, and the Master Trust Trustee are
parties to a Pooling and Servicing Agreement, dated as of June 8, 1995, and
amended by Amendment No. 1, dated as of September 12, 1995 and by Amendment No.
2, dated March 27, 1996 (as amended, the "Pooling and Servicing Agreement"). In
order to (i) include within the definition of Eligible Investments certain
additional investments and (ii) change the concentration of Eligible Investments
allowed in the Series Principal Account, Excess Funding Account, Negative Carry
Account and the Liquidity Reserve Account, the Seller, the Servicer and the
Master Trust Trustee have agreed to amend the Pooling and Servicing Agreement in
the manner set forth herein. Capitalized terms used herein but not otherwise
defined have the meanings set forth in the Pooling and Servicing Agreement.

     1. Amendment to Section 1.01. The definition of "Eligible Investments" in
Section 1.01 of the Pooling and Servicing Agreement is hereby deleted in its
entirety and replaced with the following:

     "Eligible Investments" shall mean

     (a) book-entry securities, negotiable instruments or securities represented
     by instruments in bearer or registered form having (except in the case of
     clauses (iv) or (vii) below) remaining maturities occurring not later than
     the Distribution Date next succeeding the Master Trust Trustee's
     acquisition thereof, except as otherwise described herein or the related
     Supplement, that evidence:

          (i) direct obligations of, and obligations fully guaranteed as to
          timely payment by, the United States of America;

          (ii) demand deposits, time deposits or certificates of deposit of, or
          bankers' acceptances issued by, any depository institution or trust
          company incorporated under the laws of the United States of America or
          any state thereof (or any domestic branch of a foreign bank) and
          subject to supervision and examination by federal or state banking or
          depository institution authorities; provided, however, that at the
          time of the Master Trust's investment or contractual commitment to
          invest therein, the commercial paper or other short-term unsecured
          debt obligations (other than such obligations the rating of which is
          based on the credit of a person or entity other than such depository
          institution or trust company) of such depository



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          institution or trust company shall have a credit rating not lower than
          the highest investment category for short term unsecured debt
          obligations granted by the applicable Rating Agency from each Rating
          Agency then Rating the affected Series of Investor Certificates;

          (iii) commercial paper having, at the time of the Master Trust's
          investment or contractual commitment to invest therein, a rating not
          lower than the highest investment category for short term unsecured
          debt obligations granted by the applicable Rating Agency from each
          Rating Agency then Rating the affected Series of Investor
          Certificates;

          (iv) except during an Investment Period, investments in money market
          funds or common trust funds having a rating not lower than the highest
          investment category for short term unsecured debt obligations granted
          by the applicable Rating Agency from each Rating Agency then Rating
          the affected Series of Investor Certificates or otherwise approved in
          writing by each of such Rating Agencies (including funds for which the
          Master Trust Trustee or the 1990 Trust Trustee or any of their
          respective affiliates is investment manager or advisor, so long as
          such fund shall have such rating);

          (v) repurchase obligations (x) with respect to any security that is a
          direct obligation of, or fully guaranteed by, the United States of
          America or any agency or instrumentality thereof the obligations of
          which are backed by the full faith and credit of the United States of
          America, in either case, entered into with a depository institution or
          trust company (acting as principal) described in clause (ii) or (y)
          the counterparty for which has a rating not lower than the highest
          investment category for short term unsecured debt obligations granted
          by the applicable Rating Agency from each Rating Agency then Rating
          the affected Series of Investor Certificates, the collateral for which
          is held by a custodial bank for the benefit of the Trust or the
          Indenture Trustee, is marked to market daily and is maintained in an
          amount that exceeds the amounts of such repurchase obligation, and
          which required liquidation of the collateral immediately upon the
          amount of such collateral being less than the amount of such
          repurchase obligation (unless the counterparty immediately satisfies
          the repurchase obligation upon being notified of such shortfall); or

          (vi) commercial paper master notes where the issuer has, at the time
          of the Master Trust's investment or contractual commitment to invest
          therein, a rating not lower than the highest investment category for
          short term unsecured debt obligations granted by the applicable Rating
          Agency from each Rating Agency then Rating the affected Series of
          Investor Certificates; or




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          (vii) with respect to the Excess Funding Account only, obligations of
          a trust (the assets of which consist solely of Investor Certificates
          issued by the Master Trust and of one or more liquidity swap
          arrangements for the benefit of investors in such trust) having, at
          the time of the Master Trust's investment or contractual commitment to
          invest therein, a rating not lower than the highest rating category
          for short term unsecured debt obligations granted by the applicable
          Rating Agency from each Rating Agency then Rating the affected Series
          of Investor Certificates; and

     (b) any other investment consisting of a financial asset that by its terms
     converts to cash within a finite period of time, provided that the Rating
     Agency Condition is satisfied.

     Unless the Rating Agency Condition is satisfied, Eligible Investments of
funds in the Series Principal Account, Excess Funding Account, Negative Carry
Reserve Fund and the Liquidity Reserve Account will be subject to the following
additional restrictions: (x) no more than the greater of (A) $1,000,000 and (B)
20% of the aggregate Eligible Investments in all such accounts collectively
shall be obligations of or investments in any single issuer (except that such
20% limitation shall not apply to Eligible Investments of the type specified in
clause (a)(i) or, with respect to the Excess Funding Account, Eligible
Investments of the type specified in clauses (a)(iv) or (a)(vii)); and (y) each
Eligible Investment shall be denominated and be payable solely in U.S. dollars,
shall bear interest at a specified rate that is, or is based upon, LIBOR or a
commercial paper rate, shall entitle the holder to a fixed principal amount at
maturity and shall have a yield that is not inversely or disproportionately
affected by changes in interest rates.

     2. Amendment to Section 4.02. Clause (b)(ii) of Section 4.02 of the Pooling
and Servicing Agreement is deleted in its entirety and replaced with the
following:

          "(ii) Funds on deposit in the Excess Funding Account overnight or for
     a longer period shall at all times be invested by the Master Trust Trustee
     in Eligible Investments at the direction of the Servicer or its agent,
     subject to the restrictions set forth below and in Section 4.06. Except as
     otherwise permitted by the Rating Agencies then rating the Investor
     Certificates and except for Eligible Investments of the type specified in
     clause (vii) of the definition of Eligible Investments, any Eligible
     Investments with a stated maturity shall mature no later than the following
     Transfer Date. Net interest and earnings (less investment expenses) on
     funds on deposit in the Excess Funding Account shall be included in the
     calculation of Investment Income for the relevant Due Period."

     3. Miscellaneous. This Amendment shall be construed in accordance with the
internal laws of the State of Illinois, without reference to its conflict of law
provisions, except that the obligations, rights and remedies of the Master Trust
Trustee shall be determined in accordance with the internal laws of the State of
New York, without regard to conflict of law provisions. This


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Amendment may be executed in two or more counterparts, each of which shall be an
original, but all of which together constitute one and the same instrument. The
provisions of this Amendment shall be deemed to be incorporated in, and made a
part of, the Pooling and Servicing Agreement; and the Pooling and Servicing
Agreement, as amended by this Amendment, shall be read, taken and construed as
one and the same instrument. Promptly after the execution of this Amendment the
Master Trust Trustee shall furnish written notification of the substance of this
Amendment to each Investor Certificateholder.

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     IN WITNESS WHEREOF, the parties hereto have caused this Amendment No. 3 to
the Pooling and Servicing Agreement to be duly executed by their respective
officers as of the date first written above.

                                     NAVISTAR FINANCIAL SECURITIES
                                     CORPORATION
                                              as Seller


                                     By:     /s/  RW Cain
                                         --------------------------------------

                                     Its:    Vice President & Treasurer
                                         --------------------------------------

                                     NAVISTAR FINANCIAL CORPORATION
                                              as Servicer

                                     By:     /s/  RW Cain
                                         --------------------------------------

                                     Its:    Vice President & Treasurer
                                         --------------------------------------

                                     THE BANK OF NEW YORK
                                     as Master Trust Trustee

                                     By:     /s/ Reyne A. Macadaeg
                                         --------------------------------------

                                     Its:    Assistant Vice President
                                         --------------------------------------



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