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                                                                   EXHIBIT 10(X)


                               FIRST AMENDMENT TO

                             JOINT VENTURE AGREEMENT


     THIS FIRST AMENDMENT TO JOINT VENTURE AGREEMENT is dated the 30th day of
June, 1999 (the "First Amendment") and is between Polaris Industries, Inc., a
Minnesota corporation ("Polaris") and Transamerica Commercial Finance
Corporation, a Delaware corporation ("TCFC") (collectively, Polaris and TCFC,
the "Parties" and individually, a "Party") and amends, in part, the Joint
Venture Agreement (the "JV Agreement") dated the 7th day of February, 1996
between Polaris and TCFC. All capitalized terms herein shall have the same
meaning as in the JV Agreement unless otherwise defined herein.

                                    RECITALS

     WHEREAS, Polaris and TCFC caused their respective subsidiaries, Polaris
Acceptance Inc., a Minnesota corporation ("PAI") and Transamerica Joint
Ventures, Inc. ("TJV"), a Delaware corporation (collectively, PAI and TJV the
"Partners"), to enter into a Partnership Agreement dated February 7, 1996, as it
may be amended from time to time (the "Partnership Agreement") to form an
Illinois general partnership (the "Partnership" or "PA" or "Polaris Acceptance")
for the ownership and operation of a commercial finance business and related
finance businesses within the United States and other countries supporting the
business of Polaris and its affiliates from time to time and such other
businesses as the Parties subsequently may agree, as further described therein.

     WHEREAS, PA desires to expand its business to enter into an Income Sharing
Agreement with Transamerica Retail Financial Services Corporation, a Delaware
corporation ("TRFS") dated the 30th day of June, 1999 (the "Sharing Agreement");
and

     WHEREAS, it is a condition of the Sharing Agreement that Polaris and TCFC
amend the terms of the JV Agreement as set forth in this First Amendment; and

     NOW, THEREFORE, in consideration of the premises, recitals and mutual
covenants, undertakings and obligations hereinafter set forth or referred to
herein, the Parties mutually covenant and agree as set forth below.

                                    AGREEMENT

     1.   Definitions.

          (a) The definitions of the following terms, when used in the JV
Agreement, shall, from and after the effective date of this First Amendment, be
hereby amended as follows:

               (i)  The term "Agreement" shall mean the Agreement as amended by
          this First Amendment; and

               (ii) The term "Definitive Agreements" shall (A) include the
          Sharing Agreement and (B) mean any of the Definitive Agreements as
          they may be amended from time to time, including without limitation as
          amended by the Amended Definitive Agreements.


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          (b) The following new terms shall be added to the JV Agreement as of
the effective date of this First Amendment:

               (i)   The term "First Amendment" shall mean the First Amendment
          to the JV Agreement executed by Polaris and TCFC dated the 30th day of
          June, 1999;

               (ii)  The term "Sharing Agreement" shall mean the Income Sharing
          Agreement dated the 30th day of June, 1999 between PA and TRFS;

               (iii) The term "Amended Definitive Agreements", shall have the
          same meaning as in the Sharing Agreement, and shall also include the
          (i) Manufacturer's Repurchase Agreement between Polaris Industries
          Partners, L.P. and TCFC as amended by the Second Amendment to
          Manufacturer's Repurchase Agreement executed by Polaris Industries
          Inc., a Delaware corporation and Polaris Sales Inc., a Minnesota
          corporation on the one hand, and TCFC on the other hand on the 30th
          day of June, 1999; (ii) the Revolving Program Agreement between
          Polaris and Transamerica Bank, N.A., dated the 30th day of June, 1999,
          and (iii) the Installment Program Agreement between Polaris and TRFS,
          dated the 30th day of June, 1999, as any of those or the other
          Definitive Agreements may be amended from time to time;

               (iv)  The term "Retail Effective Date" shall have the same
          meaning as in the Sharing Agreement; and

               (v)   The term "TRFS" shall mean Transamerica Retail Financial
          Services Corporation, a Delaware corporation, its successors and
          assigns.

     2.   Amended Purpose. Section 1.1, Purpose, shall be amended by adding a
subparagraph (iv) as follows:

          and (iv) an agreement to enter into the Sharing Agreement with TRFS,
     as such agreement may be amended from time to time.

     3.   Amended Location. Section 1.3, Location, shall be amended to change
the principal place of business of the Partnership from Rolling Meadows, IL. to
Hoffman Estates, IL.

     4.   Amended Notice Address. Section 7.2, Notices, shall be amended to
change the notice addresses to TCFC as follows:

          To:        TCFC   c/o Transamerica Commercial Finance Corporation
                            5595 Trillium Boulevard
                            Hoffman Estates, Illinois 60192
                            Attention: Vice President, Operations
                            Facsimile Number:  847-747-7451

          with a copy to:   General Counsel
                            Transamerica Commercial Finance Corporation
                            5595 Trillium Boulevard
                            Hoffman Estates, Illinois 60192
                            Attention: General Counsel

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                            Facsimile Number:  847-747-7455
     5.   Representations and Warranties. Each Party represents and warrants
to the other Party with respect to itself and its respective Partner subsidiary
that all representations and warranties in the JV Agreement made as of the
Closing (as defined in the JV Agreement) are made again as of the effective date
of this First Amendment.

     6.   Entire Agreement. The JV Agreement as amended by this First Amendment,
together with the other Definitive Agreements and the Amended Definitive
Agreements, as of the date hereof contain all of the understandings and
agreements of whatsoever kind and nature existing between the Parties hereto and
their respective affiliates with respect to the JV Agreement, the other
Definitive Agreements and the Amended Definitive Agreements, regarding the
subject matter hereof and the subject matter of the other Definitive Agreements
and Amended Definitive Agreements and the rights, interests, understandings,
agreements and obligations of the Parties and their respective affiliates
pertaining to the subject matter hereof and thereof and the Partnership, and
supersedes any previous agreements between the Parties and their respective
affiliates.

     7.   Governing Law. This First Amendment shall be governed by, and
construed and enforced under, the laws of the State of Illinois without regard
to conflict of law principles.

     Except as otherwise set forth herein, all terms and conditions of the JV
Agreement are hereby ratified and shall remain in full force and effect.

     IN WITNESS WHEREOF, the parties have executed this First Amendment as of
the date first above written, it being understood and agreed that it shall be
effective as of the Retail Effective Date.


                                 POLARIS INDUSTRIES INC.

                                 By:      /s/ Michael Malone
                                    --------------------------------------------

                                 Name:        Michael Malone
                                      ------------------------------------------

                                 Title: Vice President - Chief Financial Officer
                                       -----------------------------------------

                                 TRANSAMERICA COMMERCIAL FINANCE
                                        CORPORATION

                                 By:   /s/ Steven J. Toenisklette
                                    --------------------------------------------

                                 Name:     Steven J. Toenisklette
                                       -----------------------------------------

                                 Title:    Senior Vice President
                                       -----------------------------------------



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