<PAGE>
 
                                                                     EXHIBIT 4.6


                                    WARRANT
                                    -------

                         TO PURCHASE 150,000 SHARES OF
                                COMMON STOCK OF

                                 A.S.V., Inc.


     THIS CERTIFIES THAT, for good and valuable consideration, Leo Partners,
Inc., or its registered assigns ("Holder"), is entitled to subscribe for and
purchase from A.S.V., Inc., a Minnesota corporation (the "Company"), at any time
after December 1, 1997, up to and including December 1, 2006, one hundred fifty
thousand (150,000) fully paid and nonassessable shares of the Common Stock of
the Company at the price of $16.50 per share (the "Warrant Exercise Price"),
subject to the antidilution provisions of this Warrant.  Reference is made to
this Warrant in the Consulting Agreement dated as of December 1, 1996, by and
between the Company and Leo Partners, Inc. as "Consultant."  The shares which
may be acquired upon exercise of this Warrant are referred to herein as the
"Warrant Shares." As used herein, the term "Holder" means the Consultant, any
party who acquires all or a part of this Warrant as a registered transferee of
the Consultant, or any record holder or holders of the Warrant Shares issued
upon exercise, whether in whole or in part, of the Warrant; the term "Common
Stock" means and includes the Company's presently authorized common stock, $.01
par value, and shall also include any capital stock of any class of the Company
hereafter authorized which shall not be limited to a fixed sum or percentage in
respect of the rights of the holders thereof to participate in dividends or in
the distribution of assets upon the voluntary or involuntary liquidation,
dissolution, or winding up of the Company.

     This Warrant is subject to the following provisions, terms and conditions:

     1.   Exercise; Transferability.
          ------------------------- 

     (a)  Subject to the provisions of Section 3 of this Warrant, the rights
represented by this Warrant may be exercised by the Holder hereof, in whole or
in part (but not as to a fractional share of Common Stock or in amounts of fewer
than 1,000 shares of Common Stock), by written notice of exercise (in the form
attached hereto) delivered to the Company at the principal office of the Company
prior to the expiration of this Warrant and accompanied or preceded by the
surrender of this Warrant along with a certified or bank cashier's check in
payment of the Warrant Exercise Price for such shares.

     (b)  Subject to the provisions of Section 7 hereof, this Warrant shall not
be transferable at any time without the prior written consent of the Company.

     2.   Exchange and Replacement.  Subject to Section 7 hereof, this Warrant
          ------------------------                                            
is exchangeable upon the surrender hereof by the Holder to the Company at its
office for new Warrants of like tenor and date representing in the aggregate the
right to purchase the number of Warrant Shares purchasable hereunder, each of
such new Warrants to represent the right to purchase such number of Warrant
Shares (not to exceed the aggregate total number purchasable hereunder) as shall
be designated by the Holder at the time of such surrender.  Upon receipt by the
Company of evidence reasonably satisfactory to it of the loss, theft,
destruction, or mutilation of this Warrant, and, in case of loss, theft or
destruction, of indemnity or security reasonably satisfactory to it, and upon
surrender and cancellation of this Warrant, if mutilated, the Company will make
and deliver a new Warrant of like tenor, in lieu of this Warrant; provided,
however, that if the Consultant shall be such Holder, an agreement of indemnity
by such Holder shall be sufficient for all purposes of this Section 2. This
Warrant shall be promptly canceled by the
<PAGE>
 
Company upon the surrender hereof in connection with any exchange or
replacement.  The Company shall pay all expenses, taxes (other than stock
transfer taxes), and other charges payable in connection with the preparation,
execution, and delivery of Warrants pursuant to this Section 2.

     3.   Issuance of the Warrant Shares.
          ------------------------------ 

     (a)  The Company agrees that the shares of Common Stock purchased hereby
shall be and are deemed to be issued to the Holder as of the close of business
on the date on which this Warrant shall have been surrendered and the payment
made for such Warrant Shares as aforesaid.  Subject to the provisions of the
next section, certificates for the Warrant Shares so purchased shall be
delivered to the Holder within a reasonable time, not exceeding fifteen (15)
days after the rights represented by this Warrant shall have been so exercised,
and, unless this Warrant has expired, a new Warrant representing the right to
purchase the number of Warrant Shares, if any, with respect to which this
Warrant shall not then have been exercised shall also be delivered to the Holder
within such time.

     (b)  Notwithstanding the foregoing, however, the Company shall not be
required to deliver any certificate for Warrant Shares upon exercise of this
Warrant except in accordance with (i) an opinion of counsel reasonably
acceptable to it to the effect that an exemption from the applicable securities
registration requirements is available or (ii) registrations under applicable
securities laws.  Nothing herein, however, shall obligate the Company to effect
registrations under federal or state securities laws, except as provided in
Section 9.  If registrations are not in effect to the extent required as
provided in Section 9 and if the Company has not received an opinion of counsel
reasonably acceptable to it to the effect that an exemption is available when
the Holder seeks to exercise the Warrant, the Warrant exercise period will be
extended, if need be, to prevent the Warrant from expiring, until such time as
either such registrations become effective or an opinion with respect to such
exemptions is available, and the Warrant shall then remain exercisable for a
period of at least 45 calendar days from the date the Company delivers to the
Holder written notice of the availability of such registrations or exemptions.
The Holder agrees to execute such documents and make such representations,
warranties, and agreements as may be required solely to comply with the
exemptions relied upon by the Company, or the registrations made, for the
issuance of the Warrant Shares.

     4.   Covenants of the Company.  The Company covenants and agrees that all
          ------------------------                                            
Warrant Shares will, upon issuance, be duly authorized and issued, fully paid,
nonassessable, and free from all taxes, liens, and charges with respect to the
issue thereof.  The Company further covenants and agrees that during the period
within which the rights represented by this Warrant may be exercised, the
Company will at all times have authorized and reserved for the purpose of issue
or transfer upon exercise of the subscription rights evidenced by this Warrant a
sufficient number of shares of Common Stock to provide for the exercise of the
rights represented by this Warrant.

     5.   Antidilution Adjustments.  The provisions of this Warrant are subject
          ------------------------                                             
to adjustment as provided in this Section 5.

     (a)  The Warrant Exercise Price shall be adjusted from time to time such
that in case the Company shall hereafter:

          (i)    pay any dividends on any class of stock of the Company payable
     in Common Stock or securities convertible into Common Stock;

                                       2
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          (ii)   subdivide its then outstanding shares of Common Stock into a
     greater number of shares; or

          (iii)  combine outstanding shares of Common Stock, by reclassification
     or otherwise;

then, in any such event, the Warrant Exercise Price in effect immediately prior
to such event shall (until adjusted again pursuant hereto) be adjusted
immediately after such event to a price (calculated to the nearest full cent)
determined by dividing (a) the total number of shares of Common Stock
outstanding immediately prior to such event (including the maximum number of
shares of Common Stock issuable in respect of any securities convertible into
Common Stock), multiplied by the then existing Warrant Exercise Price, by (b)
the total number of shares of Common Stock outstanding immediately after such
event (including the maximum number of shares of Common Stock issuable in
respect of any securities convertible into Common Stock), and the resulting
quotient shall be the adjusted Warrant Exercise Price per share.  An adjustment
made pursuant to this subsection shall become effective immediately after the
record date in the case of a dividend or distribution and shall become effective
immediately after the effective date in the case of a subdivision, combination
or reclassification.  If, as a result of an adjustment made pursuant to this
subsection, the Holder of any Warrant thereafter surrendered for exercise shall
become entitled to receive shares of two or more classes of capital stock or
shares of Common Stock and other capital stock of the Company, the Board of
Directors (whose determination shall be conclusive) shall determine the
allocation of the adjusted Warrant Exercise Price between or among shares of
such classes of capital stock or shares of Common Stock and other capital stock.
All calculations under this subsection shall be made to the nearest cent or to
the nearest 1/100 of a share as the case may be.  In the event that at any time
as a result of an adjustment made pursuant to this subsection, the holder of any
Warrant thereafter surrendered for exercise shall become entitled to receive any
shares of the Company other than shares of Common Stock, thereafter the Warrant
Exercise Price of such other shares so receivable upon exercise of any Warrant
shall be subject to adjustment from time to time in a manner and on terms as
nearly equivalent as practicable to the provisions with respect to Common Stock
contained in this Section.

     (b)  If the Company, by dividend or otherwise, distributes to all holders
of its Common Stock evidences of its indebtedness or assets (including
securities, but excluding (i) capital stock of the Company or securities
convertible into capital stock of the Company, (ii) any sudivision or
combination of the Common Stock or (iii) any dividend or distribution paid in
cash out of the retained earnings of the Company), the Warrant Exercise Price
shall be adjusted in accordance with the following formula:

                                       3
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                          M - F
          C/1/ = C x     _______
                            M


where
 
          C/1/   =    the adjusted Warrant Exercise Price.
 
          C      =    the current Warrant Exercise Price
 
          M      =    the current Market Price (as defined in Section 8) per
                      share of Common Stock on the record date mentioned below.

          F      =    the amount of such cash dividend and/or the fair market
                      value on the record date of the assets, securities, rights
                      or warrants to be distributed divided by the number of
                      shares of Common Stock outstanding on the record date. The
                      Board of Directors of the Company shall determine the fair
                      market value.

     The adjustment shall become effective immediately after the record date for
the determination of stockholders entitled to receive the dividend or other
distribution.

     (c)  Upon each adjustment of the Warrant Exercise Price pursuant to Section
5(a) or (b) above, the Holder of each Warrant shall thereafter (until another
such adjustment) be entitled to purchase at the adjusted Warrant Exercise Price
the number of shares, calculated to the nearest full share, obtained by
multiplying the number of shares specified in such Warrant (as adjusted as a
result of all adjustments in the Warrant Exercise Price in effect prior to such
adjustment) by the Warrant Exercise Price in effect prior to such adjustment and
dividing the product so obtained by the adjusted Warrant Exercise Price.

     (d)  In case of any consolidation or merger to which the Company is a party
other than a merger or consolidation in which the Company is the continuing
corporation, or in case of any sale or conveyance to another corporation of the
property of the Company as an entirety or substantially as an entirety, or in
the case of any statutory exchange of securities with another corporation
(including any exchange effected in connection with a merger of a third
corporation into the Company), there shall be no adjustment under subsection (a)
or (b) of this Section above but the Holder of each Warrant then outstanding
shall have the right thereafter to convert such Warrant into the kind and amount
of shares of stock and other securities and property which such Holder would
have owned or have been entitled to receive immediately after such
consolidation, merger, statutory exchange, sale, or conveyance had such Warrant
been converted immediately prior to the effective date of such consolidation,
merger, statutory exchange, sale, or conveyance and in any such case, if
necessary, appropriate adjustment shall be made in the application of the
provisions set forth in this Section with respect to the rights and interests
thereafter of any Holders of the Warrant, to the end that the provisions set
forth in this Section shall thereafter correspondingly be made applicable, as
nearly as may reasonably be, in relation to any shares of stock and other
securities and property thereafter deliverable on the exercise of the Warrant.
The provisions of this subsection shall similarly apply to successive
consolidations, mergers, statutory exchanges, sales or conveyances.

     (e)  Upon any adjustment of the Warrant Exercise Price, then and in each
such case, the Company shall give written notice thereof, by first-class mail,
postage prepaid, addressed to the Holder as shown on the books of the Company,
which notice shall state the Warrant Exercise Price

                                       4
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resulting from such adjustment and the increase or decrease, if any, in the
number of shares of Common Stock purchasable at such price upon the exercise of
this Warrant, setting forth in reasonable detail the method of calculation and
the facts upon which such calculation is based.

     6.   No Voting Rights.  This Warrant shall not entitle the Holder to any
          ----------------                                                   
voting rights or other rights as a shareholder of the Company.

     7.   Notice of Transfer of Warrant or Resale of the Warrant Shares.
          ------------------------------------------------------------- 

     (a)  The Holder, by acceptance hereof, agrees to give written notice to the
Company before transferring this Warrant or transferring any Warrant Shares of
such Holder's intention to do so  (in addition to the consent required by
Section 1(b) in connection with the transfer of this Warrant), describing
briefly the manner of any proposed transfer.  Promptly upon receiving such
written notice, the Company shall present copies thereof to the Company's
counsel.  If in the opinion of such counsel the proposed transfer may be
effected without registration or qualification (under any federal or state
securities laws), the Company, as promptly as practicable, shall notify the
Holder of such opinion, whereupon the Holder shall be entitled to transfer this
Warrant or to dispose of Warrant Shares received upon the previous exercise of
this Warrant, all in accordance with the terms of the notice delivered by the
Holder to the Company; provided that an appropriate legend may be endorsed on
this Warrant or the certificates for such Warrant Shares respecting restrictions
upon transfer thereof necessary or advisable in the opinion of counsel and
satisfactory to the Company to prevent further transfers which would be in
violation of Section 5 of the Securities Act of 1933, as amended (the "1933
Act") and applicable state securities laws; and provided further that the Holder
and prospective transferee or purchaser shall execute such documents and make
such representations, warranties, and agreements as may be required solely to
comply with the exemptions relied upon by the Company for the transfer or
disposition of the Warrant or Warrant Shares.

     (b)  If in the opinion of counsel referred to in this Section 7, the
proposed transfer or disposition of this Warrant or such Warrant Shares
described in the written notice given pursuant to this Section 7 may not be
effected without registration or qualification of this Warrant or such Warrant
Shares, the Company shall promptly give written notice thereof to the Holder,
and the Holder will limit its activities in respect to such as, in the opinion
of both such counsel, are permitted by law.

     8.   Fractional Shares.  Fractional shares shall not be issued upon the
          -----------------                                                 
exercise of this Warrant, but in any case where the holder would, except for the
provisions of this Section, be entitled under the terms hereof to receive a
fractional share, the Company shall, upon the exercise of this Warrant for the
largest number of whole shares then called for, pay a sum in cash equal to the
sum of (a) the excess, if any, of the Market Price of such fractional share over
the proportional part of the Warrant Exercise Price represented by such
fractional share, plus (b) the proportional part of the Warrant Exercise Price
represented by such fractional share.  For purposes of this Warrant, the term
"Market Price" with respect to shares of Common Stock of any class or series
means the last reported sale price or, if none, the average of the last reported
closing bid and asked prices on any national securities exchange or quoted in
the National Association of Securities Dealers, Inc's Automated Quotations
System (NASDAQ), or if not listed on a national securities exchange or quoted in
NASDAQ, the average of the last reported closing bid and asked prices as
reported by Metro Data Company, Inc. from quotations by market makers in such
Common Stock on the Minneapolis-St.Paul local over-the-counter market.

                                       5
<PAGE>
 
     9.   Registration Rights.
          ------------------- 

     (a)  If at any time after December 1, 1997 and prior to the end of the two-
year period following complete exercise of this Warrant or December 1, 2008,
whichever occurs earlier, the Company proposes to register under the 1933 Act
(except by a Form S-4 or Form S-8 Registration Statement or any successor forms
thereto) or qualify for a public distribution under Section 3(b) of the 1933
Act, any of its equity securities or debt with equity features, it will give
written notice to all Holders of this Warrant, any Warrants issued pursuant to
Section 2 and/or Section 3(a) hereof, and any Warrant Shares of its intention to
do so and, on the written request of any such Holder given within twenty (20)
days after receipt of any such notice (which request shall specify the Warrant
Shares (then issued or issuable upon exercise of this Warrant) intended to be
sold or disposed of by such Holder and describe the nature of any proposed sale
or other disposition thereof), the Company will use its best efforts to cause
all such Warrant Shares, the Holders of which shall have requested the
registration or qualification thereof, to be included in such registration
statement proposed to be filed by the Company; provided, however, that if a
greater number of Warrant Shares is offered for participation in the proposed
offering than in the reasonable opinion of the managing underwriter of the
proposed offering can be accommodated without adversely affecting the proposed
offering, then the amount of Warrant Shares proposed to be offered by such
Holders for registration, as well as the number of securities of any other
selling shareholders participating in the registration, shall be proportionately
reduced to a number deemed satisfactory by the managing underwriter.

     (b)  Further, on a one-time basis only commencing December 1, 1997, upon
request by a majority in interest of Warrants, or by the holders of a majority
of the shares of the Common Stock issued upon exercise thereof, the Company
will, at its expense, promptly take all necessary steps to register or qualify
the Warrant Shares under a Registration Statement on Form S-3 or successor
thereof (provided that the Company's Common Stock is then eligible for
registration on a Form S-3 or successor thereof) under Section 3(b) or Section 5
of the Securities Act of 1933 and such state laws as such holders may reasonably
request; provided that such request must be made before the earlier of the end
of the two-year period following complete exercise of this Warrant or December
1, 2008.  The Company shall keep effective and maintain any registration,
qualification, notification or approval specified in this paragraph for such
period as may be necessary for the holders of the Warrants and such common stock
to dispose thereof and from time to time shall amend or supplement, at the
Company's expense, the prospectus or offering circular used in connection
therewith to the extent necessary in order to comply with applicable law,
provided that the Company shall not be obligated to maintain any registration
for a period of more than six (6) months after effectiveness except that a Form
S-3 Registration Statement or successor thereof shall be maintained for up to
twelve (12) months after effectiveness.  If Form S-3 is not available, the
Company will have no obligation to effect the registration provided by this
Section 9(b) until such Form S-3 is available.

     (c)  With respect to each inclusion of securities in a registration
statement pursuant to Section 9(a), the Company shall bear the following fees,
costs, and expenses: all registration, filing and NASD fees, NASDAQ fees,
printing expenses, fees and disbursements of counsel and accountants for the
Company, fees and disbursements of counsel for the underwriter or underwriters
of such securities (if the offering is underwritten and the Company is required
to bear such fees and disbursements), all internal expenses, the premiums and
other costs of policies of insurance against liability arising out of the public
offering, and legal fees and disbursements and other expenses of complying with
state securities laws of any jurisdictions in which the securities to be offered
are to be registered or qualified.  Fees and disbursements of special counsel
and accountants for the selling Holders, underwriting discounts and commissions,
and transfer taxes for selling Holders and any other expenses relating to the
sale of securities by the selling Holders not expressly included above shall be
borne by the selling Holders.

                                       6
<PAGE>
 
     (d)  The Company hereby indemnifies each of the Holders of this Warrant and
of any Warrant Shares, and the officers and directors, if any, who control such
Holders, within the meaning of Section 15 of the 1933 Act, against all losses,
claims, damages, and liabilities caused by (1) any untrue statement or alleged
untrue statement of a material fact contained in any Registration Statement or
Prospectus (and as amended or supplemented if the Company shall have furnished
any amendments thereof or supplements thereto), any Preliminary Prospectus or
any state securities law filings; (2) any omission or alleged omission to state
therein a material fact required to be stated therein or necessary to make the
statements therein not misleading, except insofar as such losses, claims,
damages, or liabilities are caused by any untrue statement or omission contained
in information furnished in writing to the Company by such Holder expressly for
use therein; and each such Holder by its acceptance hereof severally agrees that
it will indemnify and hold harmless the Company, each of its officers who signs
such Registration Statement, and each person, if any, who controls the Company,
within the meaning of Section 15 of the 1933 Act, with respect to losses,
claims, damages, or liabilities which are caused by any untrue statement or
omission contained in information furnished in writing to the Company by such
Holder expressly for use therein.

     IN WITNESS WHEREOF, A.S.V., Inc. has caused this Warrant to be signed by
its duly authorized officer and this Warrant this 1st day of December, 1996.


                              A.S.V., Inc.

                              By ______________________________________
                                 Its___________________________________

                                       7
<PAGE>
 
                                 A.S.V., INC.
                               WARRANT EXERCISE
                               ----------------

                 (TO BE SIGNED ONLY UPON EXERCISE OF WARRANT)

     The undersigned, the holder of the foregoing Warrant, hereby irrevocably
elects to exercise the purchase right represented by such Warrant for, and to
purchase thereunder, __________ shares of the Common Stock of A.S.V., Inc. to
which such Warrant relates and herewith makes payment of $ ______________
therefor in cash or by  certified or cashier's check and requests that the
certificates for such shares be issued in the name of, and be delivered to
______________________________________, whose address is set forth below the
signature of the undersigned.  If said number of shares shall not be all the
shares purchasable under the Warrant, a new Warrant is to be issued in the name
of the undersigned for the balance remaining of the shares purchasable
thereunder.

                                   Name of Warrant Holder:

                                   _________________________________________
                                   (Please print)


                                   Address of Warrant Holder:

                                   _________________________________________

                                   _________________________________________


                                   Tax Identification No. or
                                   Social Security No. of Warrant Holder:


                                   _________________________________________


                                   Signature_________________________________
                                   Note:  The above signature should correspond
                                   exactly with the name of the Warrant Holder
                                   as it appears on the first page of the
                                   Warrant or on a duly executed Warrant
                                   Assignment.

                                        Dated: _____________________

                                       8
<PAGE>
 
                                 A.S.V., INC.
                              WARRANT ASSIGNMENT
                              ------------------

                 (TO BE SIGNED ONLY UPON TRANSFER OF WARRANT)


     FOR VALUE RECEIVED, the undersigned hereby sells, assigns and transfers
unto _________________________________________________, the assignee, whose
address is ____________________________________ and whose tax identification or
social security number is ____________, the right represented by the foregoing
Warrant to purchase _______________ shares of the Common Stock of A.S.V., Inc.
to which the foregoing Warrant relates and appoints ____________________________
attorney to transfer said right on the books of A.S.V., Inc., with full power of
substitution in the premises.  If said number of shares shall not be all the
shares purchasable under the Warrant, a new Warrant is to be issued in the name
of the undersigned for the balance remaining of the shares purchasable
thereunder.

                                   Name of Warrant Holder/Assignor:
          
                                   _________________________________________
                                   (Please print)


                                   Address of Warrant Holder/Assignor:

                                   _________________________________________

                                   _________________________________________

                                   Tax Identification No. or
                                   Social Security No. of Warrant
                                   Holder/Assignor:

                                   _________________________________________


                                   Signature _________________________________
                                   NOTE:  The above signature should correspond
                                   exactly with the name on the first page of
                                   the Warrant or with the name of the assignee
                                   appearing on a duly executed assignment form.


                                   Dated: ___________________________________

                                       9