<PAGE>

                                                                  EXHIBIT 4.5.3

                              SECURITY AGREEMENT

Borrower/Debtor:                                 Lender/Secured Party:
---------------                                  --------------------

P.A.M. Transport, Inc.                           SunTrust Bank.
Highway 412 West                                 201 Fourth Avenue North
Tontitown, Arkansas 72770                        Nashville, TN 37219



       THIS SECURITY AGREEMENT is entered into this ______day of November,
2000, by and between P.A.M. Transport, Inc., an Arkansas corporation with its
principal offices located at the address set forth above ("Borrower"), and
                                                           --------
SunTrust Bank, a Georgia state chartered banking corporation with offices
located at the address set forth above ("Lender"). Intending to be legally
                                         ------
bound, Borrower and Lender agree as follows:

       1.     Security Interest and Indebtedness.  Borrower hereby grants
Lender a security interest in motor vehicles and other property described on
Exhibit A hereto, and all proceeds thereof, and all substitutions,
---------
replacements, attachments and accessions thereto (collectively, the
"Collateral"), to secure prompt and full performance and payment of (a) all
 ----------
amounts due under that certain Loan Agreement dated November 22, 2000, executed
by Borrower and Lender (as amended and/or restated from time to time, the "Loan
                                                                           ----
Agreement") and that Revolving Credit Promissory Note in the principal amount
---------
of up to Fifteen Million Dollars ($15,000,000), dated as of November 22, 2000,
executed by Borrower in favor of Lender (as amended and/or restated from time
to time, the "Note"), and all amounts that Borrower may at any time owe Lender
              ----
in connection with the Loan Agreement or the Note or any other Loan Document
(as defined in the Loan Agreement); (b) all amounts that Lender may now or
hereafter pay or advance at any time for taxes, insurance, repairs, maintenance
or other protection with respect to the Collateral; (c) all costs and expenses
that Lender may incur in enforcing or protecting its rights with respect to the
Collateral or the indebtedness secured by the Collateral, including attorneys'
fees (collectively, the "Indebtedness").
                         ------------

       2.     Representations and Warranties. Borrower hereby represents and
warrants to Lender that (a) Borrower is the sole, true and lawful owner of the
Collateral; (b) Borrower has a good unrestricted right to grant a security
interest in the Collateral; (c) there are no advances, claims, liens, security
interests or encumbrances against the Collateral except as granted to Lender;
(d) all descriptions of Collateral provided to Lender are true and accurate; and
(e) Borrower's chief executive offices and principal place(s) of business are
located at the addresses designated as such on Exhibit B hereto.
                                               ---------

       3.     Borrower's General Covenants. Borrower hereby covenants and
agrees that, until the Indebtedness has been paid in full, unless Borrower
receives the prior written consent of Lender: (a) Borrower shall keep the
Collateral free from any other lien, security interest or encumbrance, shall
maintain the Collateral in good order and repair, shall use the Collateral in
accordance with all laws, regulations and orders, and shall not sell, transfer,
or dispose of any of the Collateral; (b) Borrower shall promptly advise Lender
of any event or circumstance materially and adversely affecting the Collateral;
(c) Borrower shall pay when due all taxes and similar obligations that might
result in a lien on the Collateral if not paid. Borrower agrees to execute
additional documents and take such other actions (at its expense) as Lender may
reasonably request from time to time to implement or evidence the terms of this
Agreement.

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       4.     Perfection and Protection of Collateral. Borrower shall ensure
that Lender's security interest in the Collateral is and will remain a
perfected, first priority security interest.  Borrower shall (at its sole
expense) execute, obtain, deliver and (if applicable) file or record all
financing statements, title applications and other title documents, and take
all other actions, that Lender may deem reasonably necessary or advisable to
perfect or protect Lender's security interest in the Collateral against the
interests of third parties. Borrower hereby irrevocably appoints Lender as its
attorney-in-fact, which appointment is coupled with an interest, to take any
action that Lender may deem necessary to perfect and/or continue the perfection
of its security interests and to protect the Collateral. Borrower agrees to
pay, on demand, all costs, taxes and fees payable in connection with any such
filings or recordings. Borrower shall give Lender at least thirty (30) days
prior written notice before retitling any Collateral from its present
jurisdiction, and in each case shall (at Borrower's expense) promptly take all
steps necessary or advisable to preserve continuously the perfection and
priority of Lender's security interests in the Collateral.

       5.     Inspection. Borrower shall maintain adequate books and records
pertaining to the Collateral and shall permit Lender to visit and inspect any
of the Collateral, to examine Borrower's books of record and accounts with
respect to the Collateral, all at such reasonable times and as often as Lender
may reasonably desire.

       6.     Insurance. Borrower shall maintain casualty insurance
policies on the Collateral for its full insurable value, subject to
deductibles.  Upon Lender's request, Borrower will furnish evidence of such
insurance coverage.  Borrower shall cause (i) all insurance policies to name
Lender as an additional insured and loss payee, and (ii) all insurance policies
to provide that no assignment, cancellation, modification, reduction or adverse
change in coverage shall be effective until at least thirty (30) days after
Lender's receipt of written notice thereof.  If Borrower fails to furnish said
insurance, the Lender may do so or may obtain insurance of its interest, adding
the amount of any such premium thereof to the Indebtedness, but Lender is not
and will not be under any obligation or duty to obtain or maintain such
insurance.  Borrower hereby assigns to Lender any insurance proceeds payable
under any of its insurance policies for physical damage and directs all
insurers to pay Lender any amount so due unless the Indebtedness has been
previously satisfied.  Notwithstanding any provisions of this Section to the
contrary, Lender shall give written direction to such insurance company that
proceeds of such policies may be paid to Borrower until the insurer has been
notified that an Event of Default exists under the Loan Agreement.

       7.     Borrower's Use of the Collateral. As long as no Event of Default
has occurred,  Borrower may use the Collateral in the ordinary course of
Borrower's business, subject to any conditions set forth in this Agreement.
Upon the occurrence of an Event of Default, Borrower's right to so use the
Collateral shall terminate until further written notice from Lender.

       8.     Remedies. Upon the occurrence and continuation of an Event of
Default (as defined in the Loan Agreement), Lender shall be entitled to
exercise any or all of the rights and remedies available at law or in equity,
including the rights and remedies of a secured party under the Uniform
Commercial Code as adopted in the State of Tennessee (the "Code"). Lender's
                                                           ----
rights and remedies include the right and power to sell, at public or private
sale or sales, or otherwise collect, dispose of or use all or any portion of
the

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Collateral and any part or parts thereof in any manner authorized or permitted
under the Code. Lender may apply the proceeds thereof toward payment of the
Indebtedness and toward payment of any costs and expenses (including attorneys'
fees and legal expenses) incurred by Lender in connection with any collection,
sale or disposition of Collateral, in such order or manner as Lender may elect
in its sole discretion. Additionally, and as an essential part of the
bargained-for consideration running to Lender and to the extent permitted by
applicable law, Borrower hereby expressly grants to Lender the contractual right
to purchase any or all of the Collateral at private sale any time after ten (10)
days' notice of such sale has been sent to Borrower by Lender. Upon Lender's
demand following an Event of Default, Borrower agrees to assemble the Collateral
at its usual place of business, or at such other location as Lender may
reasonably designate, and make it available to Lender. To the extent that notice
of sale is required by applicable law, Borrower agrees that notice given as
provided in Section 13(a) hereof, at least ten (10) days before the date of the
            -------------
proposed public sale or disposition or the date after which a private sale may
be made shall be deemed reasonable and shall fully satisfy any requirement of
giving of notice. Lender may postpone and reschedule any proposed sale at its
option without the necessity of giving Borrower further notice of such fact as
long as the rescheduled sale occurs within sixty (60) days of the originally
scheduled sale. All recitals in any instrument of assignment or any other
document executed by Lender incident to sale, transfer, assignment or other
disposition or use of any Collateral hereunder shall be sufficient to establish
full legal propriety of the sale or other action taken by Lender or of any fact,
condition or thing incident thereto, and all prerequisites of such sale or other
action shall be conclusively presumed to have been performed or to have
occurred.

       9.     Borrower Waivers.  Except as expressly provided herein, and to
the fullest extent permitted by law, Borrower hereby waives (i) presentment,
demand and protest and notice of presentment, protest, default, non payment,
maturity, release, compromise, settlement, extension or renewal of any or all
commercial paper, accounts, contract rights, documents, instruments, chattel
paper and guaranties at any time held by Lender on which Borrower may in any
way be liable and hereby ratifies and confirms whatever Lender may do in this
regard; (ii) notice prior to taking possession or control of the Collateral or
any bond or security that might be required by any court before allowing Lender
to exercise any of Lender's remedies, including the issuance of an immediate
writ of possession, except as expressly required herein; (iii) any marshalling
of assets, or any right to compel Lender to resort first or in any particular
order to any other collateral or other entities before enforcing its rights as
to the Collateral or pursuing Borrower for payment of the Indebtedness; (iv)
the benefit of all valuation, appraisement and exemption laws; (v) notice of
acceptance hereof; (vi) any right to require Lender to terminate its security
interest in the Collateral before both termination of this Agreement and
payment in full of the Indebtedness; and (vi) any claims and defenses based on
principles of suretyship or impairment of collateral. Borrower acknowledges
that the foregoing waivers are a material inducement to Lender's entering into
this Agreement and that Lender is relying upon the foregoing waivers in its
future dealings with Borrower.

      10.     General Authority. Effective immediately but exercisable by
Lender (or its designee) only upon an Event of Default, Borrower hereby
irrevocably appoints Lender (or its designee) as Borrower's true and lawful
attorney-in-fact, which appointment is hereby coupled with an interest, with
full power of substitution, in Lender's name or Borrower's name or otherwise,
for Lender's sole use and benefit, but at Borrower's cost and expense, to
exercise at any time and from time to time all or any of the following powers
with respect

                                     3


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to all or any of the Collateral: (a) to receive, take, endorse, assign and/or
deliver any documents relating to the Collateral; and (b) in general, to do all
things necessary to perform the terms of this Agreement and to take any action
or proceedings that Lender deems necessary or appropriate to protect and
preserve Lender's security interest in the Collateral. In any event, however,
Lender's exercise of or failure to exercise any such authority shall in no
manner affect Borrower's liability to Lender hereunder or in connection with
the Indebtedness; Lender shall be under no obligation or duty to exercise any
of the powers hereby conferred upon Lender; and Lender shall have no liability
for any act or failure to act in connection with any of the Collateral.

      11.     Lender's Powers and Limited Duties. Lender shall have no
liability or responsibility for any diminution in the value of the Collateral
from any cause whatsoever. Lender shall be under no duty to collect any amount
that may be or become due on any of the Collateral, to redeem or realize on
Collateral, to make any presentments, demands or notices of protest in
connection with any of the Collateral, to take any steps necessary to preserve
rights in any instrument, contract or lease against third parties or to
preserve rights against prior parties, to remove any liens or to do anything
for the enforcement, collection or protection of Collateral, except to the
extent, if any, that the Code requires Lender to use reasonable care with
respect to Collateral while in its possession. Borrower agrees to pay all
taxes, charges, transfer fees and assessments against the Collateral and to do
all things necessary to preserve and maintain the value and collectibility
thereof. On Borrower's failure to so do, Lender may, after giving Borrower
written notice of its intention to do so, make such payments and advance such
sums on account thereof as Lender, in its sole discretion, deems desirable.
Borrower agrees to reimburse Lender immediately upon demand for all such
payments and advances plus interest thereon at the maximum rate allowed by
applicable law. All such amounts shall be part of the Indebtedness.

      12.     Construction, Definitions and Usage.

      (a)     Defined Terms; UCC Terms. In addition to other words and terms
              ------------------------
defined in this Agreement (including the Exhibits), the following terms have
the following meanings herein, unless the context expressly requires otherwise.
The term "business day" means any day other than a Saturday, Sunday or day on
          ------------
which commercial banks are authorized to close under the laws of the State of
Tennessee. The term "entity" means any individual, corporation, partnership,
                     ------
joint venture, association, limited liability company, joint stock company,
trust, unincorporated organization, government, or any agency or political
subdivision thereof, or any other form of entity. The terms "includes" and
                                                             --------
"including" and words of similar import are inclusive and not exclusive terms,
 ---------
and are not intended to create any limitation. All defined terms apply to both
singular and plural forms, and all references to any gender include all other
genders. Terms used in this Agreement that are defined in the Uniform
Commercial Code as adopted in the State of Tennessee (the "Code") shall have
                                                           ----
the same meanings herein, except as otherwise expressly provided or amplified
(but not limited) herein.

      (b)     Captions; Exhibits; Severability.   The captions in this
              --------------------------------
Agreement are for convenience only, and in no way limit or amplify the
provisions hereof. All Exhibits and Schedules attached hereto are by reference
made a part hereof. This Agreement is severable, and the invalidity of any
provision shall not affect any other provision hereof.

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<PAGE>

      (c)     References to Documents and Laws. All defined terms and references
              --------------------------------
as to any agreements, notes, instruments, certificates or other documents shall
be deemed to refer to such documents as they may from time to time be amended,
modified, renewed, extended, replaced, restated, supplemented or substituted.
Unless otherwise provided, all references to statutes and related regulations
shall include any amendments thereof and any successor statutes and regulations.

      13.     General Provisions.

      (a)     Notices. All notices and communications required under this
              -------
Agreement shall be given in accordance with the terms of the Loan Agreement.

      (b)     Successors and Assigns. Borrower shall not assign its rights or
              ----------------------
delegate its duties under this Agreement. Borrower's covenants and agreements
herein shall bind Borrower's successors and assigns and shall inure to the
benefit of Lender and its successors and assigns. Lender may, at its option
from time to time without notice to Borrower, assign the Indebtedness and/or
enter into participation or syndication agreements with other lenders approved
by Lender on such terms and conditions as Lender shall deem
advisable.

      (c)     Amendments and Waivers. This Agreement may not be modified or
              ----------------------
amended except in writing signed by Borrower and Lender, and none of its
provisions may be waived except in writing signed by Lender. Borrower may add
additional Collateral or substitute Collateral acceptable to Lender from time
to time by an amendment executed by Borrower and Lender in substantially the
form attached as Exhibit C.  No waivers shall be implied, whether from any
                 ---------
custom or course of dealing or any delay or failure in Lender's exercise of its
rights and remedies hereunder or otherwise. Any waiver granted by Lender shall
not obligate Lender to grant any further, similar, or other
waivers.

      (d)     Remedies.  All remedies provided to Lender herein are
              --------
cumulative, in addition to all other remedies available to Lender at law or in
equity or otherwise, and the exercise or partial exercise of any such right or
remedy shall not preclude the exercise of any other right or remedy.

      (e)     Governing Law.  This Agreement shall be construed in accordance
              -------------
with and governed by the laws of the State of Tennessee (without regard to its
rules on conflicts of laws), except to the extent, if any, that the location of
the Borrower or the Collateral may require the application of other law to
govern the perfection of security interests in the Collateral.

      (f)     Counterparts.  This Agreement may be executed in any number of
              ------------
counterparts (by facsimile transmission or otherwise), and each shall be deemed
an original but all such counterparts shall constitute but one and the same
instrument.

      (g)     Entire Agreement; No Oral Representations. This Agreement,
              -----------------------------------------
together with the Guaranty, represents the entire agreement between the parties
hereto with respect to the subject matter hereof, superseding any and all other
agreements, promises or representations existing prior to or made
simultaneously with this Agreement.

      ENTERED INTO as of the date first written above.

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<PAGE>

                                           BORROWER:
                                           ---------

Address for Notices:                       P.A.M. Transport, Inc.
-------------------

P.A.M. Transport, Inc.
P. O. Box 188                              By: /s/ Larry J. Goddard
Tontitown, Arkansas 72770                     ---------------------------------
Attn:  Larry Goddard, CFOTitle:                Title: Vice President -- Finance
FAX (501) 361-5381                                    -------------------------

                                           LENDER:
                                           -------

Address for Notices:                       SunTrust Bank
-------------------

SunTrust Bank
201 Fourth Avenue North                    By: /s/
Nashville, Tennessee 37219                    ---------------------------------
Telecopy # (615) 748-5161                  Title:______________________________
Attn: Tim Wagner or Jim Mosby

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<PAGE>

                                  EXHIBIT A
                                  ---------

Borrower/Debtor:                           Lender/Secured Party:
---------------                            --------------------

P.A.M. Transport, Inc.                     SunTrust Bank
Highway 412 West                           201 Fourth Avenue North
Tontitown, Arkansas 72770                  Nashville, Tennessee 37219

       The Collateral includes, and Borrower hereby grants to Lender a
security interest in and to, all of Borrower's right, title and interest in
the following property, all whether presently existing or hereafter acquired
and wherever located, and all additions, substitutions, replacements
extensions, amendments, attachments and accessions thereto:

(1)     See Attachment A-1 incorporated herein.

(2)     All proceeds (including insurance proceeds) of any and all of the
        foregoing, any insurance policies covering such collateral
        (collectively, "Proceeds").
                        --------

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<PAGE>

                                  EXHIBIT B
                                  ---------

                    Location Of Borrower And Collateral
                    -----------------------------------

Chief Executive Offices:

Highway 412 West
Tontitown, Arkansas 72770

Principal Place of Business in State of Tennessee

Highway 412 West
Tontitown, Arkansas 72770

Location(s) of Books and Records:

Highway 412 West
Tontitown, Arkansas 72770

Location(s) of Collateral:

Highway 412 West
Tontitown, Arkansas 72770

                                     8

<PAGE>

                                  EXHIBIT C
                                  ---------
                            (Security Agreement)

                      AMENDMENT TO SECURITY AGREEMENT
                      -------------------------------

       This Amendment to Security Agreement is made this the ____ day of
____________, 20___ by and between P.A.M. Transport, Inc. (the "Borrower") and
SunTrust Bank (the "Lender").

                                  RECITALS:
                                  --------

A.     Borrower and Lender have previously executed that certain Security
       Agreement dated as of November ____, 2000 (as it may be amended from
       time to time, the "Security Agreement").

B.     Borrower and Lender are desirous of amending the Security Agreement to
       add additional Collateral or to substitute Collateral as described on
       Exhibit A to the Security Agreement.

       NOW, THEREFORE, Borrower and Lender agree as follows:

1.     Amendment of Collateral.  Borrower and Lender agree that Exhibit A to
       -----------------------
       the Security Agreement is hereby amended by substituting the Exhibit A
       attached hereto in lieu of the prior Exhibit A.  The substitute Exhibit
       A attached hereto is hereby incorporated by reference into the Security
       Agreement.  All reference to "Collateral" in the Security Agreement
       shall refer to the amended and restated Exhibit A attached hereto and
       all provisions of the Security Agreement shall apply thereto.

2.     No Other Amendment.  Except as specifically set forth herein, no other
       ------------------
       amendment, modification or release is made pursuant to this Amendment.

       IN WITNESS WHEREOF, the undersigned, by and through their duly
       authorized officers hereby execute this Amendment as of the day and date
       first set forth above.

                                                   P.A.M. TRANSPORT, INC.


                                         By:___________________________________
                                         Title:________________________________

                                                   SUNTRUST BANK


                                         By:___________________________________
                                         Title:________________________________

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