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                                                                    EXHIBIT 99.4

                                    CUMMINS INC.

                               EXCHANGE OFFER FOR
                UP TO $250,000,000 PRINCIPAL AMOUNT OUTSTANDING
                        OF 9 1/2% SENIOR NOTES DUE 2010
                          FOR A LIKE PRINCIPAL AMOUNT
                      OF NEW 9 1/2% SENIOR NOTES DUE 2010

               PURSUANT TO THE PROSPECTUS DATED           , 2003

To: Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees:

    Cummins Inc., an Indiana corporation (the "Company"), hereby offer to
exchange (the "Exchange Offer"), upon and subject to the terms and conditions
set forth in the Prospectus dated          , 2003 (the "Prospectus") and the
enclosed letter of transmittal (the "Letter of Transmittal"), up to $250,000,000
aggregate principal amount of new 9 1/2% Senior Notes due 2010, which will be
freely transferable (the "new notes"), for any and all outstanding 9 1/2% Senior
Notes due 2010, which have certain transfer restrictions (the "original notes").
The Exchange Offer is intended to satisfy certain obligations of the Company
contained in the Registration Rights Agreement dated as of November 20, 2002,
among the Company, Salomon Smith Barney Inc. and J.P. Morgan Securities Inc.

    We are requesting that you contact your clients for whom you hold original
notes regarding the Exchange Offer. For your information and for forwarding to
your clients for whom you hold original notes registered in your name or in the
name of your nominee, or who hold original notes registered in their own names,
we are enclosing the following documents:

    1.  Prospectus dated         , 2003;

    2.  The Letter of Transmittal for your use and for the information of your
       clients;

    3.  A Notice of Guaranteed Delivery to be used to accept the Exchange Offer
       if certificates for original notes are not immediately available or time
       will not permit all required documents to reach BNY Midwest Trust Company
       c/o The Bank of New York (the "Exchange Agent") prior to the Expiration
       Date (as defined below) or if the procedure for book-entry transfer
       cannot be completed on a timely basis;

    4.  A Notice of Withdrawal to be used to withdraw tenders of original notes.

    5.  A form of letter which may be sent to your clients for whose account you
       hold original notes registered in your name or the name of your nominee,
       with space provided for obtaining such clients' instructions with regard
       to the Exchange Offer;

    6.  Guidelines for Certification of Taxpayer Identification Number on
       Substitute Form W-9; and

    7.  Return envelopes addressed to BNY Midwest Trust Company c/o The Bank of
       New York, the Exchange Agent for the original notes.

    YOUR PROMPT ACTION IS REQUESTED. THE EXCHANGE OFFER WILL EXPIRE AT
5:00 P.M., NEW YORK CITY TIME, ON             , 2003 (THE "EXPIRATION DATE"),
UNLESS EXTENDED BY THE COMPANY. ANY ORIGINAL NOTES TENDERED PURSUANT TO THE
EXCHANGE OFFER MAY BE WITHDRAWN AT ANY TIME BEFORE 5:00 P.M., NEW YORK CITY
TIME, ON THE EXPIRATION DATE.

    To participate in the Exchange Offer, a duly executed and properly completed
Letter of Transmittal (or facsimile thereof or a message from The Depository
Trust Company stating that the tendering holder has expressly acknowledged
receipt of, and agreement to be bound by and held accountable under, the Letter
of Transmittal), with any required signature guarantees and any other
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required documents, must be sent to the Exchange Agent and certificates
representing the original notes must be delivered to the Exchange Agent, all in
accordance with the instructions set forth in the Letter of Transmittal and the
Prospectus.

    If holders of original notes wish to tender, but it is impracticable for
them to forward their certificates for original notes prior to the expiration of
the Exchange Offer or to comply with the book-entry transfer procedures on a
timely basis, a tender may be effected by following the guaranteed delivery
procedures described in the Prospectus under "Exchange Offer--Guaranteed
Delivery Procedures".

    Any inquiries you may have with respect to the Exchange Offer or requests
for additional copies of the enclosed materials should be directed to the
Exchange Agent for the original notes, at its address and telephone number set
forth on the front of the Letter of Transmittal.

                                          Very truly yours,
                                          Cummins Inc.

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  NOTHING HEREIN OR IN THE ENCLOSED DOCUMENTS SHALL
  CONSTITUTE YOU OR ANY OTHER PERSON AS AN AGENT OF THE
  COMPANY OR THE EXCHANGE AGENT, OR AUTHORIZE YOU OR ANY
  OTHER PERSON TO USE ANY DOCUMENT OR MAKE ANY STATEMENTS ON
  BEHALF OF EITHER OF THEM WITH RESPECT TO THE EXCHANGE
  OFFER, EXCEPT FOR STATEMENTS EXPRESSLY MADE IN THE
  PROSPECTUS OR THE LETTER OF TRANSMITTAL.
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