Exhibit 4.1

                                VOTING AGREEMENT

     This VOTING AGREEMENT  ("Agreement") is made as of December 11, 2000, among
M. S. Carriers  Inc., a Tennessee  corporation  (the  "Company"),  the Jerry and
Vickie Moyes Family Trust dated 12/11/87, a stockholder ("Stockholder") of Swift
Transportation  Co.,  Inc., a Nevada  corporation  ("Parent"),  and Jerry Moyes,
individually ("CEO").

     WHEREAS,  Parent,  Merger Sub, and the Company are,  concurrently  with the
execution  and delivery of this  Agreement,  entering  into a Merger  Agreement,
dated as of the date hereof (the  "Merger  Agreement")  pursuant to which Merger
Sub will merge with and into the Company (the "Merger");

     WHEREAS, as of the date hereof, Stockholder and CEO together, the "Holders"
are the record and/or beneficial owners of Parent Shares (such Parent Shares the
"Existing Shares" and, together with any Parent Shares as to which record and/or
beneficial  ownership  is  acquired  after  the date  hereof,  whether  upon the
exercise  of  warrants,   options,  conversion  of  convertible  securities,  or
otherwise, the "Shares");

     WHEREAS,  as an  inducement  and a condition  to  entering  into the Merger
Agreement, the Company has required that the Holders agree, and the Holders have
agreed, to enter into this Agreement; and

     WHEREAS,  among other  things,  the  Holders and the Company  desire to set
forth their  agreement  with  respect to the voting of the Shares in  connection
with the Merger, upon the terms and subject to the conditions set forth herein.

     NOW,   THEREFORE,   in  consideration  of  the  foregoing  and  the  mutual
representations,  warranties,  covenants,  and agreements herein contained,  and
intending to be legally bound hereby, the parties hereto agree as follows:

     1. Agreement to Vote.  The Holders hereby agree that they shall,  and shall
cause any  applicable  holder of record on any  applicable  record date to, from
time to time, at the request of the Company,  at any meeting  (whether annual or
special and whether or not an adjourned or postponed meeting) of stockholders of
Parent, however called, or in connection with any written consent of the holders
of Parent Shares,  (a) if a meeting is held, appear at such meeting or otherwise
cause the Shares to be counted as present thereat for purposes of establishing a
quorum,  and (b) vote or consent (or cause to be voted or consented),  in person
or by proxy,  all Shares,  and any other voting  securities  of Parent  (whether
acquired  heretofore or hereafter) that are beneficially owned or held of record
by Holder or as to which such Holder has,  directly or indirectly,  the right to
vote or direct the voting,  in favor of the  approval of the  issuance of Parent
Shares in the Merger, and any action required in furtherance thereof.

     2. No Ownership  Interest.  Nothing  contained in this  Agreement  shall be
deemed to vest in the Company any direct or indirect  ownership  or incidence of
ownership of or with respect to any Shares. All rights,  ownership, and economic
benefits of and relating to the Shares shall remain  vested in and belong to the
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Holders.  The Company  shall have no authority to manage,  direct,  superintend,
restrict,  regulate,  govern, or administer any of the policies or operations of
Parent or exercise any power or authority to direct the Holders in the voting of
any of the Shares, except as otherwise provided herein, or in the performance of
the Holders' duties or responsibilities as a stockholder of Parent.

     3. No  Inconsistent  Agreements.  Each Holder  hereby  covenants and agrees
that, except as contemplated by this Agreement and the Merger Agreement,  it (i)
has not entered, and shall not enter at any time while this Agreement remains in
effect, into any voting agreement or voting trust with respect to the Shares and
(ii) has not  granted,  and  shall not grant at any time  while  this  Agreement
remains in effect,  a proxy,  power of attorney,  or any similar  agreement with
respect to the Shares,  in either case, which is inconsistent with such Holder's
obligations pursuant to this Agreement.

     4.  Agreement of CEO.  CEO hereby  agrees that he will use his best efforts
cause any entity  controlled  by him to vote any Parent Shares held of record by
such entity in favor of the  approval  and  adoption  of the  issuance of Parent
Shares in the Merger, and any action required in furtherance thereof.

     5.  Authorization;  Validity of Agreement;  Necessary  Action.  Each of the
Holders has full power and authority to execute and deliver this  Agreement,  to
perform  its  obligations   hereunder,   and  to  consummate  the   transactions
contemplated hereby. This Agreement has been duly executed and delivered by each
of the Holders,  and,  assuming this  Agreement  constitutes a valid and binding
obligation of the Company,  constitutes  a valid and binding  obligation of each
Holder, enforceable against it in accordance with its terms.

     6.  Adjustments.  In the event of a stock dividend or distribution,  or any
change  in  Parent   Shares   by  reason  of  any  stock   dividend,   split-up,
recapitalization,  combination,  exchange  of  shares,  or the  like,  the  term
"Shares"  shall be deemed to refer to and include the Shares as well as all such
stock dividends and  distributions and any shares into which or for which any or
all of the Shares may be changed or exchanged.  The Holders shall be entitled to
receive any cash dividend paid by the Parent during the term of this Agreement.

     7. Termination.  This Agreement shall terminate and no party shall have any
rights or duties  hereunder  upon the earlier of (a) the  Effective  Time or (b)
termination of the Merger Agreement.  Nothing in this Section 8 shall relieve or
otherwise limit any party of liability for breach of this Agreement.

     8.  Capacity.  The  obligations  of each Holder herein are made only in its
capacity as a stockholder of Parent.

     9.  Notices.  All  notices or other  communications  which are  required or
permitted  hereunder shall be in writing and sufficient if delivered  personally
or sent by nationally recognized overnight courier or by registered or certified
mail, postage prepaid,  return receipt requested,  or by electronic mail, with a
copy  thereof to be  delivered  or sent as  provided  above or by  facsimile  or
telecopier.  All such notices or  communications  shall be deemed to be received
(i) in the case of personal delivery,  nationally  recognized overnight courier,
or  registered  or certified  mail, on the date of such delivery and (ii) in the
case of facsimile or telecopier or electronic mail, upon confirmed receipt.

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     10.  Severability.  If any term or other  provision  of this  Agreement  is
invalid,  illegal,  or incapable of being enforced by any rule of Law, or public
policy, all other conditions and provisions of this Agreement shall nevertheless
remain in full force and effect so long as the  economic or legal  substance  of
the  transactions  contemplated  hereby is not affected in any manner adverse to
any party. Upon such  determination that any term or other provision is invalid,
illegal,  or incapable of being enforced,  the parties hereto shall negotiate in
good faith to modify this  Agreement so as to effect the original  intent of the
parties  as  closely  as  possible  in an  acceptable  manner  to the  end  that
transactions contemplated hereby are fulfilled to the extent possible.

     11.  Amendments;  Assignment.  This  Agreement may not be amended except by
written  agreement by all the parties.  This Agreement shall be binding upon and
inure  to the  benefit  of the  parties  and  their  respective  successors  and
permitted assigns.  Neither this Agreement nor any of the rights,  interests, or
obligations under this Agreement shall be assigned,  in whole or in part, by any
of the parties without the prior written  consent of the other parties,  and any
purported assignment without such consent shall be void.

     12. Failure or Indulgence Not Waiver;  Remedies  Cumulative.  No failure or
delay on the part of any party  hereto in the  exercise  of any right  hereunder
will impair such right or be  construed to be a waiver of, or  acquiescence  in,
any breach of any  representation,  warranty,  or agreement herein, nor will any
single or partial  exercise of any such right preclude other or further exercise
thereof  or of any other  right.  All rights and  remedies  existing  under this
Agreement  are  cumulative  to, and not  exclusive to, and not exclusive of, any
rights or remedies otherwise available.

     13. Entire  Agreement.  This  Agreement  constitutes  the entire  agreement
between the Company and the Holders  with respect to the subject  matter  hereof
and supersedes all prior agreements and  understandings,  both written and oral,
between the Company and either Holder with respect to the subject matter hereof.

     14.   Counterparts.   This  Agreement  may  be  executed  in  one  or  more
counterparts, and by the different parties hereto in separate counterparts, each
of which when executed shall be deemed to be an original, but all of which taken
together shall constitute one and the same agreement.

     15.  Governing Law. This  Agreement  shall be governed by, and construed in
accordance  with,  the  laws of the  State of  Nevada  applicable  to  contracts
executed in and to be performed entirely within that state.

     16. Specific Performance.  The parties hereto agree that irreparable damage
would occur in the event any  provision of this  Agreement  is not  performed in

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accordance  with the terms  hereof,  and that the  parties  shall be entitled to
specific performance of the terms hereof, in addition to any other remedy at law
or in equity.

     17.  Definitions.  Capitalized  terms used herein and not otherwise defined
herein shall have the meanings given in the Merger Agreement.

     IN WITNESS WHEREOF,  the Company and the Holders have caused this Agreement
to be signed by their respective  officers or other authorized  person thereunto
duly authorized as of the date first written above.


M. S. Carriers, Inc.
a Tennessee corporation


By: /s/ Michael S. Starnes
   --------------------------------
   Chairman of the Board, President
   and Chief Executive Officer


THE JERRY AND VICKIE MOYES FAMILY TRUST DATED 12/11/87

By: /s/ Jerry Moyes
   --------------------
   Jerry Moyes, Trustee

By: /s/ Vickie Moyes
   ---------------------
   Vickie Moyes, Trustee



/s/ Jerry Moyes
-----------------------
Jerry Moyes, Individually

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