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                                                                    EXHIBIT 10.4

                              FOURTH AMENDMENT TO
                          LOAN AND SECURITY AGREEMENT


          This Fourth Amendment to Loan and Security Agreement (this
"Amendment"), is made and entered into effective as of the 12th day of March,
1998 by and between FINOVA CAPITAL CORPORATION, a Delaware corporation
("Lender") and AMERITRUCK DISTRIBUTION CORP., a Delaware corporation
("Borrower").  This Amendment modifies and amends that certain Loan and Security
Agreement, dated May 5, 1997, between Lender and Borrower (the "Agreement").
All terms used herein with initial capital letters, unless otherwise
specifically defined herein, shall have the same meanings as set forth in the
Agreement.  All references to the Agreement shall include the Schedule.

                                R E C I T A L S:

          WHEREAS, Borrower has requested that Lender extend the Additional
Availability Period so that Borrower may have sufficient time to consummate a
private placement of its capital stock for Twenty Million Dollars ($20,000,000);

          WHEREAS, in connection therewith, Borrower and Lender desire to amend
the Agreement in certain respects;

          NOW, THEREFORE, in consideration of the foregoing premises and other
valuable consideration, the parties hereto agree as follows:

          1.   Amendment to Schedule. Subject to the terms and conditions of
Section 2 below, the Agreement is amended as follows:

          (a)  The definition of "Additional Availability Period" set forth in
Section 18.1 of the Agreement is amended and restated as follows:

          "Additional Availability Period" means the period commencing on
     November 13, 1997 and ending on the earliest of (A) May 15, 1998, (B) the
     date a Qualified Private Placement is consummated, (C) the date a Qualified
     Thompson Bros. Sale is consummated, and (D) the date Borrower notifies
     Lender in writing of its desire to terminate the Additional Availability
     Period.

          (b)  The definition of "Qualified Private Placement" set forth in
Section 18.1 of the Agreement is amended and restated as follows:

          "Qualified Private Placement" means any non-public sale of shares of
     any class of Borrower's capital stock yielding gross cash proceeds to
     Borrower of at least Ten Million Dollars ($10,000,000).

          (c)  Section 18.1 of the Agreement shall be amended to add the
following definition in the appropriate alphabetical order:
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          "Qualified Thompson Bros. Sale" means any sale of the stock or
     substantially all of the assets of Thompson Bros., Inc. yielding Borrower
     gross cash proceeds of at least Ten Million Dollars ($10,000,000).

          (d)  Section 1.1 of the Schedule to the Agreement is amended and
restated in its entirety as follows:

     TOTAL FACILITY (Section 1.1):  Sixty Million Dollars ($60,000,000);
                                    provided, that during the Additional
                                    Availability Period, the Total Facility
                                    shall be Sixty-Eight Million Five Hundred
                                    Thousand Dollars ($68,500,000)

          (e)  Section 1.2 of the Schedule to the Agreement is amended and
restated in its entirety as follows:

     LOANS (SECTION 1.2):

                                    REVOLVING LOANS: a revolving line of credit
                                    (The "Revolving Loans") consisting of loans
                                    against Eligible Receivables and against
                                    Eligible Equipment in an aggregate
                                    outstanding principal amount not to exceed
                                    the lesser of:

                                    (a)  Total Facility

                                    (b)  the sum of:

                                         (i)   an amount equal to eighty-five
                                               percent (85%) of the net amount
                                               of the Eligible Receivables that
                                               are billed; plus

                                         (ii)  an amount (not to exceed the
                                               lesser of (A) Four Million
                                               Dollars ($4,000,000) and (B) an
                                               amount equal to three (3) working
                                               days' revenue (based on the most
                                               recent monthly financials)) equal
                                               to seventy (70%) of Eligible
                                               Receivables that are unbilled
                                               less than five (5) Business Days;
                                               plus

                                         (iii) an amount equal to the Equipment
                                               Advance Rate multiplied by the
                                               Orderly Liquidation Value of the
                                               Eligible Equipment; plus

                                         (iv)  during the Additional
                                               Availability Period only, an
                                               amount equal to five 

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                                               percent (5%) of the net amount of
                                               the Eligible Receivables that are
                                               billed; plus

                                         (v)   during the Additional
                                               Availability Period only, an
                                               amount equal to the product of
                                               (A) the amount by which eighty
                                               percent (80%) exceeds the
                                               Equipment Advance Rate multiplied
                                               by (B) the Orderly Liquidation
                                               Value of the Eligible Equipment;
                                               less

                                         (vi)  the aggregate undrawn face amount
                                               of all Letters of Credit issued
                                               under Section 1.4 of this
                                               Agreement; less

                                         (vii) the amount of the Landlord
                                               Reserve and such other reserves
                                               as Lender, in its reasonable
                                               credit judgment, deems proper
                                               from time to time based on the
                                               results of its examinations,
                                               Appraisals or other credit or
                                               collateral considerations which
                                               indicate a deterioration in
                                               Eligible Receivables or Eligible
                                               Equipment from the date hereof,
                                               such that additional reserves for
                                               Eligible Receivables and/or
                                               Eligible Equipment are warranted.

                            Notwithstanding the foregoing, (A) the loans against
                            Eligible Equipment shall not exceed Thirty-Five
                            Million Dollars ($35,000,000) at any time, (B) the
                            loans against the availability described in clauses
                            (iv) and (v) shall not exceed Eight Million Five
                            Hundred Thousand Dollars ($8,500,000) and (C) the
                            availability described in clauses (iv) and (v) above
                            shall not be available at any time other than during
                            the Additional Availability Period. The Revolving
                            Loans shall be segregated into two tranches:
                            revolving loans under tranche A (the "Revolving A
                            Loans") and revolving loans under tranche B (the
                            "Revolving B Loans"). The maximum outstanding
                            principal amount of Revolving A Loans is Thirty
                            Million Dollars ($30,000,000) and the maximum
                            outstanding principal amount of Revolving B Loans is
                            Thirty Million Dollars ($30,000,000); provided, that
                            during the Availability Period, the maximum
                            outstanding principal amount of Revolving

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                            B Loans shall be Thirty-Eight Million Five Hundred
                            Thousand Dollars ($38,500,000). With respect to each
                            request for a Revolving Loan or Letter of Credit,
                            Borrower shall designate whether such request is for
                            a Revolving A Loan (or under the tranche for
                            Revolving A Loans in the case of Letters of Credit)
                            or a Revolving B Loan (or under the tranche for
                            Revolving B Loans in the case of Letters of Credit).
                            With each request for a Revolving B Loan (or a
                            Letter of Credit to be issued under the tranche for
                            Revolving B Loans), Borrower shall provide Lender
                            with a certificate of the chief financial officer of
                            Borrower, in form and substance satisfactory to
                            Lender that such Revolving B Loan or Letter of
                            Credit, as applicable, will not result in a breach
                            or violation of the Indenture, and at the request of
                            Lender, with an opinion of Borrower's counsel that
                            such Revolving B Loan or Letter of Credit, as
                            applicable, will not result in a breach or violation
                            of the Indenture.

          (f) Section 3.1(E) of the Schedule to the Agreement is amended and
restated in its entirety as follows:

                            E.   Fees for Additional Availability Period.
                                 Borrower has previously paid to Lender an
                                 Additional Availability Facility Fee equal to
                                 Three Hundred Thirty Thousand Dollars
                                 ($330,000).  In addition to the foregoing,
                                 Borrower shall pay to Lender another Additional
                                 Availability Facility Fee equal to Two Hundred
                                 Eighty Thousand Dollars ($280,000) which shall
                                 be payable as follows:  (i) Ninety Thousand
                                 Dollars ($90,000) on March 12, 1998, (ii)
                                 $90,000 on April 12, 1998 and (iii) One Hundred
                                 Thousand Dollars ($100,000) on May 15, 1998;
                                 provided that upon termination of the
                                 Additional Availability Period, the entire
                                 unpaid Additional Availability Facility Fee
                                 shall be immediately due and payable.

          2.  Intentionally Omitted.

          3.  Other Agreements. Prior to the end of the Additional Availability
Period, Borrower agrees to enter into, and to cause its operating subsidiaries
to enter into, blocked account and lockbox agreements, each in form and
substance reasonably satisfactory to Lender, and consistent with drafts
previously reviewed and approved by Borrower, with

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Lender and NationsBank of Texas, N.A. Borrower also agrees that, in lieu of
compensating Lender for prepaying a LIBOR Rate Portion prior to the end of an
Interest Period as provided in Section 3.1(A)(vi)(e)(2), if at any time the
aggregate unpaid principal balance of the Revolving Loans is less than the
aggregate LIBOR Rate Options for LIBOR Rate Portions requested by Borrower (the
amount by which such Revolving Loans are less than such aggregate LIBOR Rate
Options being referred to as the "LIBOR Deficiency"), the most recent LIBOR Rate
Option shall be converted to a Base Rate Option retroactive to the first day of
the Interest Period pertaining to such LIBOR Rate Option and the portion of the
Revolving Loans applicable to such LIBOR Rate Option shall (from the first day
of such Interest Period) bear interest at a per annum rate equal to two and
three-quarters percent (2.75%) in excess of the Base Rate; provided, that if the
LIBOR Deficiency is less than Two Million Dollars ($2,000,000), instead of
converting the most recent LIBOR Rate Option to a Base Rate Option as provided
above, Borrower shall pay to Lender a fee of Two Hundred Fifty Dollars ($250)
for each day the LIBOR Deficiency is less than Two Million Dollars ($2,000,000)
but greater than Zero (0). Further, Borrower agrees that it will at all times
maintain Base Rate Loans of at least Two Million Dollars ($2,000,000). Finally,
Borrower agrees to cooperate fully with Taylor & Martin and Lender in connection
with an Appraisal to be conducted by Taylor & Martin.

          4.  Confirmation of Liens. This Amendment in no way acts as a release
or relinquishment of any of the liens, security interests, rights or remedies
securing payment of the Loans or of the enforcement thereof. Such liens,
security interests, rights and remedies are hereby ratified, confirmed,
preserved, renewed and extended by Borrower in all respects.

          5.  Events of Default. The Events of Default specified in the
Agreement and the other Loan Documents shall continue to be the Events of
Default under the Loans except as otherwise specifically agreed herein to the
contrary. Lender's remedies with respect to the occurrence of an Event of
Default shall continue to be as set forth in the Loan Documents.

          6.  Reaffirmation of the Loan Documents. All terms, conditions and
provisions of the Agreement and the other Loan Documents are hereby reaffirmed
and continued in full force and effect and shall remain unaffected and unchanged
except as specifically amended hereby.

          7.  Representations and Warranties. Borrower represents and warrants
to Lender that the execution and delivery by Borrower of this Amendment has been
duly and properly made and authorized. The Loan Documents and this Amendment
each constitute valid and binding obligations of Borrower, enforceable in
accordance with their respective terms.

          8.  Benefit of the Amendment. The terms and provisions of this
Amendment and the other Loan Documents shall be binding upon and inure to the
benefit of Lender and Borrower and their respective successors and assigns,
except that Borrower shall 

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not have any right to assign its rights under this Amendment or any of the Loan
Documents or any interest therein without the prior written consent of Lender.

          9.  Choice of Law. The Loan Documents and this Amendment shall be
performed and construed in accordance with the laws of the State of Arizona.

         10.  Entire Agreement. Except as modified by this Amendment, the Loan
Documents remain in full force and effect. The Loan Documents, as modified by
this Amendment, embody the entire agreement and understanding between Borrower
and Lender, and supersede all prior agreements and understandings between said
parties relating to the subject matter thereof.

         11.  Counterparts; Telecopy Execution. This Amendment may be executed
in any number of separate counterparts, each of which, when taken together,
shall constitute one and the same agreement, admissible into evidence,
notwithstanding the fact that all parties have not signed the same counterpart.
Delivery of an executed counterpart of this Amendment by telefacsimile shall be
equally as effective as delivery of a manually executed counterpart of this
Amendment. Any party delivering an executed counterpart of this Amendment by
telefacsimile shall also deliver a manually executed counterpart of this
Amendment, but the failure to deliver a manually executed counterpart shall not
affect the validity, enforceability, and binding effect of this Amendment.

          IN WITNESS WHEREOF, the parties hereto have executed this Amendment
effective as of the day, month, and year first above written.


                                        FINOVA CAPITAL CORPORATION, a Delaware 
                                        corporation
 
 
                                        By
                                          --------------------------------------
                                        Name
                                            ------------------------------------
                                        Title
                                             -----------------------------------
 
                                        AMERITRUCK DISTRIBUTION CORP., a 
                                        Delaware corporation


                                        By
                                          --------------------------------------
                                        Name
                                            ------------------------------------
                                        Title
                                             -----------------------------------
 

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<PAGE>
 
                          REAFFIRMATION OF GUARANTORS


                             DATED MARCH 12, 1998


          Each of the undersigned hereby (i) confirms that it has read the
foregoing Consent and First Amendment Agreement, and (ii) reaffirms its
obligations under the Continuing Guaranty that it executed in favor of FINOVA
Capital Corporation.


                     AMERITRUCK EQUIPMENT CORP.
                     AMERITRUCK LOGISTICS SERVICES, INC.
                     AMERITRUCK REFRIGERATED TRANSPORT, INC.
                     J.C. BANGERTER & SONS, INC.
                     CMS TRANSPORTATION SERVICES, INC.
                     KTL, INC.
                     SCALES TRANSPORTATION CORPORATION
                     SCALES LEASING COMPANY, INC.
                     THOMPSON BROS., INC.
                     W&L SERVICES CORP.
                     W&L MOTOR LINES, INC.
                     AMERITRUCK OPERATIONS SERVICES, INC.
                     BEST WAY MOTOR LINES, INC.
                     BILLINGS TRUCKING CORPORATION
                     BLS INVESTMENTS, INC.
                     CAS SERVICE COMPANY
                     CAS TRANSPORTATION, INC.
                     FRONTIER FREIGHT, INC.
                     MONFORT TRANSPORTATION COMPANY
                     LYNN TRANSPORTATION CO.
                     TRANS-STAR, INC.
                     PRO-TRANS SERVICES, INC.
 
 
                     By
                        --------------------------------------
                     Name
                          ------------------------------------
                     Title                                     of each Guarantor
                           -----------------------------------

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