EXHIBIT 99.1

                         SWIFT TRANSPORTATION CO., INC.
                           ANTICIPATES SECOND QUARTER
                       RESULTS WILL BE BELOW EXPECTATIONS

     Phoenix, AZ - June 6, 2001 -- Swift  Transportation Co., Inc.  (NASDAQ-NMS:
SWFT)  announced that it expects its second quarter results to fall short of the
consensus of published analysts'  expectations,  which we believe to be 16 cents
per share.  Individual estimates range from a low of 9 cents per share to a high
of 28 cents per share.  The Company  believes that the current  estimates do not
include a previously  announced one-time increase in insurance reserves of $9 to
$13 million that it expects to take after it closes the M.S. Carriers merger. It
also does not  reflect  M.S.  Carriers  results for the second  quarter,  or the
additional  outstanding  shares to be outstanding  upon closing the merger.  The
Company expects its earnings for the quarter,  prior to any effects  relating to
M.S. Carriers, such as the insurance adjustment, to be between 8 to 12 cents per
share, based upon the 64.6 million shares outstanding as of today's date.

     Jerry Moyes,  Chairman,  President & Chief  Executive  Officer  stated "The
economy  continues to be weak,  the freight demand is still soft, and we believe
that the interest rate cuts by the Federal Reserve still have not stimulated the
economy to any significant extent."

     The Company  expects that the M.S.  Carriers merger will be approved by the
shareholders of both Swift and M.S.  Carriers at their June 15 annual  meetings,
and the transaction will be completed prior to June 30, 2001.

     This news release contains  statements that may constitute  forward-looking
statements,  usually  identified  by words  such as  "anticipates,"  "believes,"
"estimates," "projects," "expects" or similar expressions.  These statements are
made pursuant to the safe harbor provisions of the Private Securities Litigation
Reform Act of 1995. Such statements include,  but are not limited to, statements
concerning Swift's projected earnings and financial  performance,  recent trends
in  freight  demand,  the  proposed  acquisition  of M.S.  Carriers,  and  other
information. Such statements are based upon the current beliefs and expectations
of Swift's  management and are subject to significant  risks and  uncertainties.
Actual  results  may  differ  from  those  set  forth  in  the   forward-looking
statements.  As to Swift's  business and financial  performance  generally,  the
following factors, among others, could cause actual results to differ materially
from  those in  forward-looking  statements:  excess  capacity  in the  trucking
industry;  significant increases or rapid fluctuations in fuel prices,  interest
rates, fuel taxes, tolls,  license and registration fees, insurance premiums and
driver  compensation,  to the extent not offset by increases in freight rates or
fuel surcharges;  difficulty in attracting and retaining  qualified  drivers and
owner  operators,  especially  in light of the  current  shortage  of  qualified
drivers and owner  operators;  recessionary  economic  cycles and  downturns  in
customers' business cycles, particularly in market segments and industries (such
as retail and  manufacturing) in which Swift has a significant  concentration of
customers;  seasonal  factors such as harsh  weather  conditions  that  increase
operating  costs;  increases in driver  compensation to the extent not offset by
increases  in  freight  rates;  the  inability  of Swift to  continue  to secure
acceptable financing arrangements;  the ability of Swift to continue to identify
and combine acquisition candidates that will result in successful  combinations;
an  unanticipated  increase  in the  number  of claims  for which  Swift is self
insured;  competition  from  trucking,  rail and intermodal  competitors;  and a
significant  reduction in or termination of Swift's  trucking  services by a key
customer. With respect to the proposed acquisition of M.S. Carriers, these risks
and  uncertainties   include:   the  failure  of  Swift's  and  M.S.   Carriers'
stockholders  to approve the merger;  the risk that the  businesses  will not be
integrated successfully or that integration costs will exceed our estimates; the
risk that the revenue and other  synergies  and cost savings from the merger may
not be fully realized or may take longer to realize than  expected;  fluctuating
stock market  levels;  the  difficulty  the stock market may have in valuing the
business model of the combined company; and disruption from the merger making it
more difficult to maintain relationships with customers, employees or suppliers.

     A discussion of these and other factors that could cause Swift's results to
differ materially from those described in the forward-looking  statements can be
found  in the most  recent  Annual  Reports  on  Forms  10-K of  Swift  and M.S.
Carriers, filed with the Securities and Exchange Commission and available at the
Securities and Exchange Commission's internet site  (http://www.sec.gov).  Swift
undertakes  no  obligation  to  publicly  update or revise  any  forward-looking
statements, whether as a result of new information, future events, or otherwise.
Further,  nothing  herein shall  constitute  adoption or approval of any analyst
report  regarding Swift, nor any undertaking to update or comment upon analysts'
expectations in the future.

     The  proposed  merger with M.S.  Carriers  will be submitted to Swift's and
M.S.  Carriers'  stockholders  for  their  consideration.   Swift  has  filed  a
registration   statement   on   Form   S-4   that   includes   a   joint   proxy
statement/prospectus.    STOCKHOLDERS    SHOULD    READ    THE    JOINT    PROXY
STATEMENT/PROSPECTUS REGARDING THE PROPOSED TRANSACTION THAT HAS BEEN FILED WITH
THE SEC  AND  MAILED  TO  STOCKHOLDERS.  THE  JOINT  PROXY  STATEMENT/PROSPECTUS
CONTAINS IMPORTANT  INFORMATION THAT STOCKHOLDERS SHOULD CONSIDER.  Stockholders
may obtain a free copy of the joint proxy statement/prospectus, as well as other
filings containing information about Swift and M.S. Carriers, without charge, at
the  SEC's  internet  site  (http://www.sec.gov).  Copies  of  the  joint  proxy
statement/prospectus  and the SEC filings that are  incorporated by reference in
the joint proxy  statement/prospectus  can also be obtained,  without charge, by
directing a request to: Swift  Transportation Co., Inc., 2200 South 75th Avenue,
Phoenix, AZ 85043, Attention: Chief Financial Officer (602-269-9700).

     Swift and M.S. Carriers and certain other persons named below may be deemed
to be participants in the solicitation of proxies of Swift's and M.S.  Carriers'
stockholders to approve the transaction.  The participants in this  solicitation
may include the directors and executive officers of Swift and M.S.  Carriers.  A
detailed list of the names and  interests of Swift's  directors and officers and
M.S.  Carriers'   directors  and  officers  is  contained  in  the  joint  proxy
statement/prospectus.

     As of the date of this  communication,  none of the foregoing  participants
individually beneficially owns in excess of 5% of Swift's common stock, or 5% of
M.S. Carriers' common stock,  except that Jerry Moyes, CEO of Swift beneficially
owns more than 5% of the common  stock of Swift and Michael S.  Starnes,  CEO of
M.S.  Carriers,  beneficially  owns  more  than 5% of the  common  stock of M.S.
Carriers.  Certain  employees  of M.S.  Carriers,  including  participants,  may
receive accelerated vesting of their stock options in connection with the merger
in accordance with their existing stock option agreements. In addition,  certain
officers of M.S.  Carriers,  as a condition  to the closing of the merger,  will
enter into employment  agreements that will become  effective upon completion of
the merger. A description of the employment agreements is contained in the joint
proxy statement/prospectus.

     Swift  is the  holding  company  for  Swift  Transportation  Co.,  Inc.,  a
truckload carrier headquartered in Phoenix,  Arizona. Swift is the third largest
publicly-held  national  truckload  carrier in the United  States with  regional
operations throughout the continental United States.