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Exhibit 5.1





                                  July 2, 1996




Caliber System, Inc.
3560 W. Market Street
Akron, Ohio  44334-0459

  Re:  $400,000,000 Aggregate Amount of Debt
       Securities of Caliber System, Inc.   
       -------------------------------------

Gentlemen:

   We are acting as counsel for Caliber System, Inc., an Ohio corporation (the
"Company"), in connection with the creation and authorization of the issuance
and sale of up to $400,000,000 aggregate amount of Debt Securities (the
"Securities"), to be issued pursuant to an Indenture (the "Indenture") to be
entered into between the Company and Chemical Bank, as Trustee (the "Trustee").

   We have examined such documents, records and matters of law as we have
deemed necessary for purposes of this opinion, and based thereupon, but subject
to the assumptions and qualifications set forth below, we are of the opinion
that:

   1.  The Indenture has been duly authorized and, when duly executed and
delivered by the Company and the Trustee, will constitute a valid and binding
instrument of the Company.

   2.  The Securities have been duly authorized and, when duly executed,
authenticated and delivered to and paid for by the purchasers thereof in
accordance with the terms of such Securities and the Indenture, will be valid
and binding obligations of the Company and will be entitled to the benefits of
the Indenture.

   In rendering the foregoing opinions we have also assumed that (i) the
definitive information, including, without limitation, the definitive terms of
the Securities, remaining to be completed in the form of Indenture relating to
the Securities





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Caliber System, Inc.
July 2, 1996
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as filed as Exhibit 4.1 to the Registration Statement filed by the Company to
effect registration of the Securities under the Securities Act of 1933 (the
"Registration Statement"), will be so completed and the Indenture and
Securities will be duly authorized by the Board of Directors of the Company
(the "Board") or its duly authorized designee in such form with such
completions, (ii) the Underwriting Agreement will be executed and delivered by
the Company and the Underwriters in substantially the form filed as Exhibit 1.1
to the Registration Statement, and (iii) any duly authorized action to be taken
by the Board or its designee, as of the date of this opinion, will remain duly
authorized and not be revoked by any subsequent Board action.

   We hereby consent to the filing of this opinion as Exhibit 5.1 to the
Registration Statement on Form S-3 filed by the Company to effect registration
of the Securities under the Securities Act of 1933 and to the reference to us
under the caption "Validity of Debt Securities" in the Prospectus constituting
a part of such Registration Statement.

                                Very truly yours,


                                Jones, Day, Reavis & Pogue