March 5, 2003

Smithway Motor Xpress, Inc.
2031 Quail Avenue
Fort Dodge, Iowa 50501

And

East West Motor Express, Inc.
1170 JB drive
Black Hawk, South Dakota 57718

Re:  Third Amendment to Amended and Restated Loan and Security
     Agreement

Gentlemen:

     Smithway Motor Xpress, Inc., an Iowa corporation ("Smithway Inc.") and East
West Motor Express,  Inc., a South Dakota  corporation  ("East West")  (Smithway
Inc. and East West each a  "Borrower"  and  collectively  the  "Borrowers")  and
LaSalle Bank National Association,  a national banking association ("Bank") have
entered into that certain Amended and Restated Loan and Security Agreement dated
December  28, 2001 (the  "Security  Agreement").  From time to time  thereafter,
Borrowers and Bank may have executed various amendments (each an "Amendment" and
collectively the "Amendments") to the Security Agreement (the Security Agreement
and  the  Amendments   hereinafter  are  referred  to,   collectively,   as  the
"Agreement").  Borrowers  and Bank now desire to further  amend the Agreement as
provided herein, subject to the terms and conditions hereinafter set forth.

     NOW,  THEREFORE,  in  consideration of the foregoing  recitals,  the mutual
covenants  and   agreements  set  forth  herein  and  other  good  and  valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
parties hereto hereby agree as follows:

     1.   The Agreement hereby is amended as follows:

     (a)  Subsection  2(a) of the  Agreement  is deleted in its entirety and the
following is substituted in its place:

     2.   LOANS.

     (a) Revolving Loans.


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Smithway Motor Xpress, Inc.
East West Motor Express, Inc.
March 5, 2003
Page 2

          Subject to the terms and  conditions  of this  Agreement and the Other
     Agreements,  during the Original Term and any Renewal  Term,  Lender shall,
     absent the  occurrence  of an Event of Default,  make  revolving  loans and
     advances to Borrowers' (the  "Revolving  Loans") in an amount up to the sum
     of the following sublimits (the "Revolving Loan Limit"):

          (i) Up to  eighty-five  percent  (85%),  or such lesser  percentage as
     determined by Lender in its sole  discretion  determined in good faith,  of
     the face amount (less maximum  discounts,  credits and allowances which may
     be taken by or granted to Account  Debtors in  connection  therewith in the
     ordinary  course of Borrowers'  business) of Borrowers'  Eligible  Accounts
     (consisting  solely of  Eligible  Accounts  other  than  those set forth at
     subsection (ii) immediately below); plus

          (ii) Up to  eighty-five  percent (85%),  or such lesser  percentage as
     determined by Lender in its sole  discretion  determined in good faith,  of
     the face amount (less maximum  discounts,  credits and allowances which may
     be taken by or granted to Account  Debtors in  connection  therewith in the
     ordinary  course of Borrowers'  business) of Borrowers'  Eligible  Accounts
     (consisting  solely of Accounts  which are  unbilled  for three (3) days or
     less)  or  Two  Million   Five   Hundred   Thousand   and  No/100   Dollars
     ($2,500,000.00), whichever is less; plus

          (iii) Up to One Million Two Hundred Fifty  Thousand and No/100 Dollars
     ($1,250,000.00) as a Special Accommodation from March 4, 2003 through March
     18, 2003;  which shall reduce  automatically  to Two Hundred Fifty Thousand
     and No/100  Dollars  ($250,000.00)  from March 19, 2003  through  April 30,
     2003, at which time,  commencing May 1, 2003 and  thereafter,  such Special
     Accommodation shall automatically reduce to zero ($0); minus

          (iv) such reserves as Lender elects, in its sole discretion determined
     in good faith to establish from time to time;

     provided, that the Revolving Loan Limit shall in no event exceed Thirty-Two
     Million Five Hundred Thousand and No/100 Dollars  ($32,500,000.00) less the
     then-outstanding   principal  balance  of  the  Term  Loans  (the  "Maximum
     Revolving Loan Limit") except as such amount may be increased or, following
     the  occurrence  of an Event of Default,  decreased by Lender,  in its sole
     discretion.

          The aggregate  unpaid  principal  balance of the Revolving Loans shall
     not at any time exceed the lesser of the (i) Revolving Loan Limit minus the

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Smithway Motor Xpress, Inc.
East West Motor Express, Inc.
March 5, 2003
Page 3

     Letter of Credit  Obligations  and (ii) the  Maximum  Revolving  Loan Limit
     minus  the  Letter of Credit  Obligations.  If at any time the  outstanding
     Revolving  Loans  exceeds  either the  Revolving  Loan Limit or the Maximum
     Revolving Loan Limit, in each case minus the Letter of Credit  Obligations,
     or any  portion of the  Revolving  Loans and  Letter of Credit  Obligations
     exceeds any applicable sublimit within the Revolving Loan Limit,  Borrowers
     shall  immediately,  and without the necessity of demand by Lender,  pay to
     Lender such amount as may be necessary to eliminate  such excess and Lender
     shall apply such payment to the Revolving Loans to eliminate such excess.

          Each Borrower hereby  authorizes  Lender,  in its sole discretion,  to
     charge any of such Borrower's  accounts or advance  Revolving Loans to make
     any payments of principal, interest, fees, costs or expenses required to be
     made under this Agreement or the Other Agreements.

          A request for a Revolving  Loan shall be made or shall be deemed to be
     made, each in the following manner: the Borrower  requesting such Revolving
     Loan shall give Lender same day notice,  no later than 10:30 A.M.  (Chicago
     time) for such day, of its  request  for a  Revolving  Loan as a Prime Rate
     Loan.  In the event that a Borrower  maintains  a  controlled  disbursement
     account at Lender, each check presented for payment against such controlled
     disbursement  account and any other  charge or request for payment  against
     such  controlled  disbursement  account  shall  constitute  a request for a
     Revolving  Loan as a Prime Rate Loan.  As an  accommodation  to  Borrowers,
     Lender may permit  telephone  requests for Revolving  Loans and  electronic
     transmittal  of  instructions,  authorizations,  agreements  or  reports to
     Lender by  Borrowers.  Unless a  Borrower  specifically  directs  Lender in
     writing not to accept or act upon  telephonic or electronic  communications
     from such  Borrower,  Lender shall have no  liability to Borrowers  for any
     loss or damage  suffered by a Borrower as a result of Lender's  honoring of
     any requests,  execution of any instructions,  authorizations or agreements
     or  reliance  on  any  reports   communicated  to  it   telephonically   or
     electronically and purporting to have been sent to Lender by a Borrower and
     Lender shall have no duty to verify the origin of any such communication or
     the authority of the Person sending it.

          Each Borrower  hereby  irrevocably  authorizes  Lender to disburse the
     proceeds of each Revolving Loan requested by such Borrower, or deemed to be
     requested by such Borrower, as follows: the proceeds of each Revolving Loan
     requested  under  Section 2(a) shall be disbursed by Lender in lawful money
     of the United States of America in  immediately  available

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Smithway Motor Xpress, Inc.
East West Motor Express, Inc.
March 5, 2003
Page 4

     funds, by wire transfer or Automated  Clearing House (ACH) transfer to such
     bank account as may be agreed upon by such Borrower and Lender from time to
     time, or elsewhere if pursuant to a written direction from such Borrower.

     (b)  Subsection  4(a) of the  Agreement  is deleted in its entirety and the
following is substituted in its place:

     4. INTEREST, FEES AND CHARGES.

     (a) Interest Rate.

          Each Loan  shall bear  interest  at the rate of two  percent  (2%) per
     annum in excess of the Prime Rate in effect  from time to time,  payable on
     the last Business Day of each month in arrears. Said rate of interest shall
     increase or decrease by an amount equal to each increase or decrease in the
     Prime Rate effective on the effective date of each such change in the Prime
     Rate. Upon the occurrence of an Event of Default and during the continuance
     thereof,  each Loan shall bear interest at the rate of two percent (2%) per
     annum in excess of the  interest  rate  otherwise  payable  thereon,  which
     interest  shall be payable on demand.  All interest  shall be calculated on
     the basis of a 365-day year.

     (c)  Subsection  4(b) of the  Agreement  is deleted in its entirety and the
following is substituted in its place:

          (iv) One-Time  Fee:  Borrowers  shall pay to Lender a one-time  fee of
               Twenty-Five Thousand and No/100 Dollars  ($25,000.00),  which fee
               shall  be  fully  earned  and  payable  upon  execution  of  this
               Amendment.

     2. This Amendment  shall not become  effective  until fully executed by all
parties hereto.

     3.  Except  as  expressly  amended  hereby  and by any  other  supplemental
documents or instruments  executed by either party hereto in order to effectuate
the transactions contemplated hereby, the Agreement and Exhibit A thereto hereby
are  ratified and  confirmed by the parties  hereto and remain in full force and
effect in accordance with the terms thereof.

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Smithway Motor Xpress, Inc.
East West Motor Express, Inc.
March 5, 2003
Page 5

                               LASALLE BANK NATIONAL ASSOCIATION

                               By      /s/ John Mostofi
                                  --------------------------------
                               Title     Sr VP
                                     -----------------------------


ACKNOWLEDGED AND AGREED TO
this 5th day of March, 2003:

SMITHWAY MOTOR XPRESS, INC.

By  /s/ William G. Smith
   -----------------------------
     William G. Smith

Title:  President

EAST WEST MOTOR EXPRESS, INC.

By  /s/ William G. Smith
   -----------------------------
     William G. Smith

Title:  President


Consented and agreed to by the following
guarantor(s) of the obligations of SMITHWAY
MOTOR XPRESS, INC. and EAST WEST MOTOR
EXPRESS, INC. to LASALLE BANK NATIONAL
ASSOCIATION.

SMSD ACQUISITION CORP.

By  /s/ G. Larry Owens
   -----------------------------
     G. Larry Owens

Title: Vice President

Date:  March 5, 2003

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Smithway Motor Xpress, Inc.
East West Motor Express, Inc.
March 5, 2003
Page 6


SMITHWAY MOTOR XPRESS CORP.

By  /s/ G. Larry Owens
   -----------------------------
     G. Larry Owens

Title: Vice President

Date:  March 5, 2003







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