<PAGE>

                                                                    Exhibit 4.30

                                                                            FORM


                               GUARANTEE AGREEMENT

                                     Between

                                   ONEOK, INC.

                                 (as Guarantor)

                                       and

                                  SUNTRUST BANK

                                  (as Trustee)

                                   dated as of

                                ________________,

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                             CROSS-REFERENCE TABLE*

         Section of
     Trust Indenture Act                                      Section of
     of 1939, as amended                                  Guarantee Agreement
   -----------------------                              -----------------------

           310(a).                                            4.1(a)
           310(b).                                            4.1(c), 2.8
           310(c).                                            Inapplicable
           311(a).                                            2.2(b)
           311(b).                                            2.2(b)
           311(c).                                            Inapplicable
           312(a).                                            2.2(a)
           312(b).                                            2.2(b)
           313.                                               2.3
           314(a).                                            2.4
           314(b).                                            Inapplicable
           314(c).                                            2.5
           314(d).                                            Inapplicable
           314(e).                                            1.1, 2.5, 3.2
           314(f).                                            2.1, 3.2
           315(a).                                            3.1(d)
           315(b).                                            2.7
           315(c).                                            3.1
           315(d).                                            3.1(d)
           316(a).                                            1.1, 2.6, 5.4
           316(b).                                            5.3
           316(c)                                             8.2
           317(a).                                            Inapplicable
           317(b).                                            Inapplicable
           318(a).                                            2.1(b)
           318(b).                                            2.1
           318(c).                                            2.1(a)

-----
*    This Cross-Reference Table does not constitute part of the Guarantee
     Agreement and shall not affect the interpretation of any of its terms or
     provisions.

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                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                                         Page
<S>                                                                                      <C>
ARTICLE I.  DEFINITIONS ................................................................    1
  Section 1.1.   Definitions. ..........................................................    1
ARTICLE II.  TRUST INDENTURE ACT .......................................................    3
  Section 2.1. Trust Indenture Act; Application ........................................    3
  Section 2.2. List of Holders .........................................................    4
  Section 2.3. Reports by the Guarantee Trustee ........................................    4
  Section 2.4. Periodic Reports to the Guarantee Trustee ...............................    4
  Section 2.5. Evidence of Compliance with Conditions Precedent ........................    4
  Section 2.6. Events of Default; Waiver ...............................................    4
  Section 2.7. Event of Default; Notice ................................................    5
  Section 2.8. Conflicting Interests ...................................................    5
ARTICLE III.  POWERS, DUTIES AND RIGHTS OF THE GUARANTEE TRUSTEE .......................    5
  Section 3.1. Powers and Duties of the Guarantee Trustee ..............................    5
  Section 3.2. Certain Rights of Guarantee Trustee .....................................    7
  Section 3.3. Indemnity ...............................................................    8
ARTICLE IV.  GUARANTEE TRUSTEE .........................................................    9
  Section 4.1. Guarantee Trustee: Eligibility ..........................................    9
  Section 4.2. Appointment, Removal and Resignation of the Guarantee Trustee ...........    9
ARTICLE V.  GUARANTEE ..................................................................   10
  Section 5.1. Guarantee ...............................................................   10
  Section 5.2. Waiver of Notice and Demand .............................................   10
  Section 5.3. Obligations Not Affected ................................................   10
  Section 5.4. Rights of Holders .......................................................   11
  Section 5.5. Guarantee of Payment ....................................................   11
  Section 5.6. Subrogation .............................................................   11
  Section 5.7. Independent Obligations .................................................   11
ARTICLE VI.  COVENANTS AND SUBORDINATION ...............................................   12
  Section 6.1. Subordination ...........................................................   12
  Section 6.2. Pari Passu Guarantees ...................................................   12
ARTICLE VII.  TERMINATION ..............................................................   12
  Section 7.1. Termination .............................................................   12
ARTICLE VIII.  MISCELLANEOUS ...........................................................   12
  Section 8.1. Successors and Assigns ..................................................   12
  Section 8.2. Amendments ..............................................................   13
  Section 8.3. Notices .................................................................   13
  Section 8.4. Benefit .................................................................   14
  Section 8.5. Interpretation ..........................................................   14
  Section 8.6. Governing Law ...........................................................   14
</TABLE>

<PAGE>

                               GUARANTEE AGREEMENT

     This GUARANTEE AGREEMENT, dated as of ________, is executed and delivered
by ONEOK, INC., an Oklahoma corporation ("ONEOK") having its principal office at
100 West Fifth Street, Tulsa, Oklahoma 74103, and SUNTRUST BANK, a Georgia
banking corporation with trust powers, as trustee (the "Guarantee Trustee"), for
the benefit of the Holders (as defined herein) from time to time of the
Preferred Securities (as defined herein) of ONEOK Capital Trust I, a Delaware
statutory trust (the "Issuer").

     WHEREAS, pursuant to an Amended and Restated Trust Agreement dated as of
__________, (the "Trust Agreement") among ONEOK, as Depositor, the Property
Trustee, the Administrative Trustee and the Delaware Trustee named therein and
the Holders from time to time of undivided beneficial interests in the assets of
the Issuer, the Issuer is issuing $_________ aggregate Liquidation Amount (as
defined in the Trust Agreement) of its ____% [Trust Preferred Securities]
(Liquidation Amount $[25] per Preferred Security) (the "Preferred Securities"),
representing preferred undivided beneficial interests in the assets of the
Issuer and having the terms set forth in the Trust Agreement;

     WHEREAS, the Preferred Securities will be issued by the Issuer and the
proceeds thereof, together with the proceeds from the issuance of the Issuer's
Common Securities (as defined below), will be used to purchase the Notes (as
defined in the Trust Agreement) of ONEOK which will be deposited with SUNTRUST
BANK, as Property Trustee under the Trust Agreement, as trust assets; and

     WHEREAS, as incentive for the Holders to purchase Preferred Securities
ONEOK desires irrevocably and unconditionally to agree, to the extent set forth
herein, to pay to the Holders of the Preferred Securities the Guarantee Payments
(as defined herein) and to make certain other payments on the terms and
conditions set forth herein.

     NOW, THEREFORE, in consideration of the purchase by each Holder of
Preferred Securities, which purchase ONEOK hereby agrees shall benefit ONEOK,
and intending to be legally bound hereby, ONEOK executes and delivers this
Guarantee Agreement for the benefit of the Holders from time to time of the
Preferred Securities.

                              ARTICLE I DEFINITIONS

     Section 1.1 Definitions.

     As used in this Guarantee Agreement, the terms set forth below shall,
unless the context otherwise requires, have the following meanings. Capitalized
or otherwise defined terms used but not otherwise defined herein shall have the
meanings assigned to such terms in the Trust Agreement as in effect on the date
hereof.

     "Affiliate" of any specified Person means any other Person directly or
indirectly controlling or controlled by or under direct or indirect common
control with such specified Person; provided, however, that an Affiliate of
ONEOK shall not be deemed to be an Affiliate of the Issuer. For the purposes of
this definition, "control" when used with respect to any specified Person means
the power to direct the management and policies of such Person, directly or

<PAGE>

indirectly, whether through the ownership of voting securities, by contract or
otherwise; and the terms "controlling" and "controlled" have meanings
correlative to the foregoing.

     "Board of Directors" means either the board of directors of ONEOK or the
Guarantee Trustee, as the case may be, or any committee of that board duly
authorized to act hereunder.

     "Common Securities" means the securities representing common undivided
beneficial interests in the assets of the Issuer.

     "Event of Default" means a default by ONEOK on any of its payment or other
obligations under this Guarantee Agreement; provided, however, that, except with
respect to a default in payment of any Guarantee Payments, ONEOK shall have
received notice of default and shall not have cured such default within 60 days
after receipt of such notice.

     "Guarantee Payments" means the following payments or distributions, without
duplication, with respect to the Preferred Securities, to the extent not paid or
made by or on behalf of the Issuer: (i) any accrued and unpaid Distributions (as
defined in the Trust Agreement) required to be paid on the Preferred Securities,
to the extent the Issuer shall have funds on hand available therefor at such
time, (ii) the redemption price, including all accrued and unpaid Distributions
to the date of redemption (the "Redemption Price"), with respect to any
Preferred Securities called for redemption by the Issuer, to the extent the
Issuer shall have funds on hand available therefor at such time, and (iii) upon
a voluntary or involuntary dissolution, termination, winding-up or liquidation
of the Issuer, unless Notes are distributed to the Holders, the lesser of (a)
the aggregate of the Liquidation Amount of $[25] per Preferred Security plus
accrued and unpaid Distributions on the Preferred Securities to the date of
payment, to the extent the Issuer shall have funds on hand available to make
such payment at such time and (b) the amount of assets of the Issuer remaining
available for distribution to Holders in liquidation of the Issuer (in either
case, the "Liquidation Distribution").

     "Guarantee Trustee" means SUNTRUST BANK, until a Successor Guarantee
Trustee has been appointed and has accepted such appointment pursuant to the
terms of this Guarantee Agreement, and thereafter means each such Successor
Guarantee Trustee.

     "Holder" means any holder, as registered on the books and records of the
Issuer, of any Preferred Securities; provided, however, that in determining
whether the holders of the requisite percentage of Preferred Securities have
given any request, notice, consent or waiver hereunder, "Holder" shall not
include ONEOK, the Guarantee Trustee, or any Affiliate of ONEOK or the Guarantee
Trustee.

     "Indenture" means the Junior Subordinated Indenture dated of even date
herewith, as supplemented and amended, between ONEOK and SUNTRUST BANK, as
trustee.

     "List of Holders" has the meaning specified in Section 2.2(a).

     "Majority in Liquidation Amount of the Securities" means, except as
provided by the Trust Indenture Act, a vote by the Holder(s), voting separately
as a class, of more than 50% of the aggregate Liquidation Amount of all then
outstanding Preferred Securities issued by the Issuer.

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     "Officers' Certificate" means, with respect to any Person, a certificate
signed by the Chairman or a Vice Chairman of the Board of Directors of such
Person or the Chief Executive Officer, President or a Vice President of such
Person, and by the Treasurer, an Assistant Treasurer, the Secretary or an
Assistant Secretary of such Person, and delivered to the Guarantee Trustee. Any
Officers' Certificate delivered with respect to compliance with a condition or
covenant provided for in this Guarantee Agreement shall include:

     (a) a statement that each officer signing the Officers' Certificate has
read the covenant or condition and the definitions relating thereto;

     (b) a brief statement of the nature and scope of the examination or
investigation undertaken by each officer in rendering the Officers' Certificate;

     (c) a statement that each officer has made such examination or
investigation as, in such officer's opinion, is necessary to enable such officer
to express an informed opinion as to whether or not such covenant or condition
has been complied with; and

     (d) a statement as to whether, in the opinion of each officer, such
condition or covenant has been complied with.

     "Person" means a legal person, including any individual, corporation,
estate, partnership, joint venture, association, joint stock company, limited
liability company, trust, unincorporated association, or government or any
agency or political subdivision thereof, or any other entity of whatever nature.

     "Responsible Officer" means, with respect to the Guarantee Trustee, any
Senior Vice President, any Vice President, any Assistant Vice President, the
Secretary, any Assistant Secretary, the Treasurer, any Assistant Treasurer, any
Trust Officer or Assistant Trust Officer or any other officer of the Corporate
Trust Department of the Guarantee Trustee and also means, with respect to a
particular corporate trust matter, any other officer to whom such matter is
referred because of that officer's knowledge of and familiarity with the
particular subject.

     "Successor Guarantee Trustee" means a successor Guarantee Trustee
possessing the qualifications to act as Guarantee Trustee under Section 4.1.

     "Trust Indenture Act" means the Trust Indenture Act of 1939, as amended.

                         ARTICLE II TRUST INDENTURE ACT

     Section 2.1 Trust Indenture Act; Application.

     (a) This Guarantee Agreement is subject to the provisions of the Trust
Indenture Act that are required to be part of this Guarantee Agreement and
shall, to the extent applicable, be governed by such provisions.

     (b) If and to the extent that any provision of this Guarantee Agreement
limits, qualifies or conflicts with the duties imposed by Sections 310 to 317,
inclusive, of the Trust Indenture Act, such imposed duties shall control. If any
provision of this Guarantee Agreement

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modifies or excludes any provision of the Trust Indenture Act that may be so
modified or excluded, the latter provision shall be deemed to apply to this
Guarantee Agreement as so modified or excluded, as the case may be.

     Section 2.2 List of Holders.

     (a) ONEOK shall furnish or cause to be furnished to the Guarantee Trustee
(a) quarterly, on or before January 15, April 15, July 15 and October 15 of each
year, a list, in such form as the Guarantee Trustee may reasonably require, of
the names and addresses of the Holders ("List of Holders") as of a date not more
than 15 days prior to the delivery thereof, and (b) at such other times as the
Guarantee Trustee may request in writing, within 30 days after the receipt by
ONEOK of any such request, a List of Holders as of a date not more than 15 days
prior to the time such list is furnished, in each case to the extent such
information is in the possession or control of ONEOK and is not identical to a
previously supplied List of Holders or has not otherwise been received by the
Guarantee Trustee in its capacity as such. The Guarantee Trustee may destroy any
List of Holders previously given to it on receipt of a new List of Holders.

     (b) The Guarantee Trustee shall comply with its obligations under Section
311(a), Section 311(b) and Section 312(b) of the Trust Indenture Act.

     Section 2.3 Reports by the Guarantee Trustee.

     Not later than 60 days following May 15 of each year, commencing May 15,
200__, the Guarantee Trustee shall provide to the Holders such reports as are
required by Section 313 of the Trust Indenture Act, if any, in the form and in
the manner provided by Section 313 of the Trust Indenture Act. The Guarantee
Trustee shall also comply with the requirements of Section 313(d) of the Trust
Indenture Act.

     Section 2.4 Periodic Reports to the Guarantee Trustee.

     ONEOK shall provide to the Guarantee Trustee, the Securities and Exchange
Commission and the Holders such documents, reports and information, if any, as
required by Section 314 of the Trust Indenture Act and the compliance
certificate required by Section 314 of the Trust Indenture Act, in the form, in
the manner and at the times required by Section 314 of the Trust Indenture Act.

     Section 2.5 Evidence of Compliance with Conditions Precedent.

     ONEOK shall provide to the Guarantee Trustee such evidence of compliance
with such conditions precedent, if any, provided for in this Guarantee Agreement
that relate to any of the matters set forth in Section 314(c) of the Trust
Indenture Act. Any certificate or opinion required to be given by an officer
pursuant to Section 314(c)(1) may be given in the form of an Officers'
Certificate.

     Section 2.6 Events of Default; Waiver.

                                        4

<PAGE>

     The Holders of a Majority in Liquidation Amount of the Securities may, by
vote, on behalf of the Holders, waive any past Event of Default and its
consequences. Upon such waiver, any such Event of Default shall cease to exist,
and any Event of Default arising therefrom shall be deemed to have been cured,
for every purpose of this Guarantee Agreement, but no such waiver shall extend
to any subsequent or other default or Event of Default or impair any right
consequent therefrom.

     Section 2.7 Event of Default; Notice.

     (a) The Guarantee Trustee shall, within 90 days after the occurrence of an
Event of Default actually known to the Guarantee Trustee, transmit by mail,
first class postage prepaid, to the Holders, notices of all such Events of
Default, unless such defaults have been cured or waived before the giving of
such notice, provided, that, except in the case of a default in the payment of a
Guarantee Payment, the Guarantee Trustee shall be protected in withholding such
notice if and so long as the Board of Directors, the executive committee or a
trust committee of directors and/or Responsible Officers of the Guarantee
Trustee in good faith determines that the withholding of such notice is not
adverse to the interests of the Holders.

     (b) The Guarantee Trustee shall not be deemed to have knowledge of any
Event of Default unless the Guarantee Trustee shall have received written
notice, or a Responsible Officer charged with the administration of this
Guarantee Agreement shall have received written notice, of such Event of
Default.

     Section 2.8 Conflicting Interests.

     The Trust Agreement and the Indenture shall be deemed to be specifically
described in this Guarantee Agreement for the purposes of clause (i) of the
first proviso contained in Section 310(b) of the Trust Indenture Act.

         ARTICLE III POWERS, DUTIES AND RIGHTS OF THE GUARANTEE TRUSTEE

     Section 3.1 Powers and Duties of the Guarantee Trustee.

     (a) This Guarantee Agreement shall be held by the Guarantee Trustee for the
benefit of the Holders, and the Guarantee Trustee shall not transfer this
Guarantee Agreement to any Person except a Holder exercising his or her rights
pursuant to Section 5.4(iv) or to a Successor Guarantee Trustee on acceptance by
such Successor Guarantee Trustee of its appointment to act as Successor
Guarantee Trustee. The right, title and interest of the Guarantee Trustee, as
such, hereunder shall automatically vest in any Successor Guarantee Trustee,
upon acceptance by such Successor Guarantee Trustee of its appointment
hereunder, and such vesting and cessation of title shall be effective whether or
not conveyancing documents have been executed and delivered pursuant to the
appointment of such Successor Guarantee Trustee.

     (b) If an Event of Default has occurred and is continuing, the Guarantee
Trustee shall enforce this Guarantee Agreement for the benefit of the Holders.

     (c) The Guarantee Trustee, before the occurrence of any Event of Default
and after the cure or waiver of all Events of Default that may have occurred,
shall undertake to perform

                                       5

<PAGE>

only such duties as are specifically set forth in this Guarantee Agreement, and
no implied covenants shall be read into this Guarantee Agreement against the
Guarantee Trustee. In case an Event of Default has occurred (that has not been
cured or waived pursuant to Section 2.6), the Guarantee Trustee shall exercise
such of the rights and powers vested in it by this Guarantee Agreement, and use
the same degree of care and skill in its exercise thereof, as a prudent person
would exercise or use under the circumstances in the conduct of his or her own
affairs.

     (d) No provision of this Guarantee Agreement shall be construed to relieve
the Guarantee Trustee from liability for its own negligent action, its own
negligent failure to act or its own willful misconduct, except that:

          (i)   This subsection shall not be construed to limit subsections (b)
     and (c) of this Section;

          (ii)  prior to the occurrence of any Event of Default and after the
     curing or waiving of all such Events of Default that may have occurred:

                (A) the duties and obligations of the Guarantee Trustee shall be
          determined solely by the express provisions of this Guarantee
          Agreement, and the Guarantee Trustee shall not be liable except for
          the performance of such duties and obligations as are specifically set
          forth in this Guarantee Agreement; and

                (B) in the absence of bad faith on the part of the Guarantee
          Trustee, the Guarantee Trustee may conclusively rely, as to the truth
          of the statements and the correctness of the opinions expressed
          therein, upon any certificates or opinions furnished to the Guarantee
          Trustee and conforming to the requirements of this Guarantee
          Agreement; but in the case of any such certificates or opinions that
          by any provision hereof or of the Trust Indenture Act are specifically
          required to be furnished to the Guarantee Trustee, the Guarantee
          Trustee shall be under a duty to examine the same to determine whether
          or not they conform to the requirements of this Guarantee Agreement;

          (iii) the Guarantee Trustee shall not be liable for any error of
     judgment made in good faith by a Responsible Officer of the Guarantee
     Trustee, unless it shall be proved that the Guarantee Trustee was negligent
     in ascertaining the pertinent facts upon which such judgment was made;

          (iv)  the Guarantee Trustee shall not be liable with respect to any
     action taken or omitted to be taken by it in good faith in accordance with
     the direction of the Holders of not less than a Majority in Liquidation
     Amount of the Securities relating to the time, method and place of
     conducting any proceeding for any remedy available to the Guarantee
     Trustee, or exercising any trust or power conferred upon the Guarantee
     Trustee under this Guarantee Agreement; and

          (v)   no provision of this Guarantee Agreement shall require the
     Guarantee Trustee to expend or risk its own funds or otherwise incur
     personal financial liability in the performance of any of its duties or in
     the exercise of any of its rights or powers, if the Guarantee Trustee shall
     have reasonable grounds for believing that the repayment of such

                                       6

<PAGE>

     funds or liability is not reasonably assured to it under the terms of this
     Guarantee Agreement or adequate indemnity against such risk or liability is
     not reasonably assured to it.

     Section 3.2 Certain Rights of Guarantee Trustee.

     (a) Subject to the provisions of Section 3.1:

          (i)   The Guarantee Trustee may conclusively rely and shall be fully
     protected in acting or refraining from acting upon any resolution,
     certificate, statement, instrument, opinion, report, notice, request,
     direction, consent, order, bond, debenture, note, other evidence of
     indebtedness or other paper or document reasonably believed by it to be
     genuine and to have been signed, sent or presented by the proper party or
     parties.

          (ii)  Any direction or act of the Guarantor contemplated by this
     Guarantee Agreement shall be sufficiently evidenced by an Officers'
     Certificate unless otherwise prescribed herein.

          (iii) Whenever, in the administration of this Guarantee Agreement, the
     Guarantee Trustee shall deem it desirable that a matter be proved or
     established before taking, suffering or omitting to take any action
     hereunder, the Guarantee Trustee (unless other evidence is herein
     specifically prescribed) may, in the absence of bad faith on its part,
     request and conclusively rely upon an Officers' Certificate which, upon
     receipt of such request from the Guarantee Trustee, shall be promptly
     delivered by ONEOK.

          (iv)  The Guarantee Trustee may consult with legal counsel of its
     selection, and the advice or written opinion of such legal counsel with
     respect to legal matters shall be full and complete authorization and
     protection in respect of any action taken, suffered or omitted to be taken
     by it hereunder in good faith and in accordance with such advice or
     opinion. Such legal counsel may be legal counsel to ONEOK or any of its
     Affiliates and may be one of its employees. The Guarantee Trustee shall
     have the right at any time to seek instructions concerning the
     administration of this Guarantee Agreement from any court of competent
     jurisdiction.

          (v)   The Guarantee Trustee shall be under no obligation to exercise
     any of the rights or powers vested in it by this Guarantee Agreement at the
     request or direction of any Holder, unless such Holder shall have provided
     to the Guarantee Trustee such adequate security and indemnity as would
     satisfy a reasonable person in the position of the Guarantee Trustee,
     against the costs, expenses (including attorneys' fees and expenses) and
     liabilities that might be incurred by it in complying with such request or
     direction, (including such reasonable advances as may be requested by the
     Guarantee Trustee; provided that, nothing contained in this Section
     3.2(a)(v) shall be taken to relieve the Guarantee Trustee, upon the
     occurrence of an Event of Default, of any obligation it may have to
     exercise the rights and powers vested in it by this Guarantee Agreement).

          (vi)  The Guarantee Trustee shall not be bound to make any
     investigation into the facts or matters stated in any resolution,
     certificate, statement, instrument, opinion,

                                       7

<PAGE>

     report, notice, request, direction, consent, order, bond, debenture, note,
     other evidence of indebtedness or other paper or document, but the
     Guarantee Trustee, in its discretion, may make such further inquiry or
     investigation into such facts or matters as it may see fit.

          (vii)  The Guarantee Trustee may execute any of the trusts or powers
     hereunder or perform any duties hereunder either directly or by or through
     its agents or attorneys, and the Guarantee Trustee shall not be responsible
     for any negligence or willful misconduct on the part of any such agent or
     attorney appointed with due care by it hereunder.

          (viii) Whenever in the administration of this Guarantee Agreement the
     Guarantee Trustee shall deem it desirable to receive instructions with
     respect to enforcing any remedy or right or taking any other action
     hereunder, the Guarantee Trustee (A) may request instructions from the
     Holders, which written instructions may only be given by the Holders of the
     same portion in aggregate liquidation amount of the Preferred Securities as
     would be entitled to direct the Guarantee Trustee under the terms of this
     Guarantee Agreement, (B) may refrain from enforcing such remedy or right or
     taking such other action until such instructions are received, and (C)
     shall be fully protected in acting in accordance with such instructions.

     (b)  No provision of this Guarantee Agreement shall be deemed to impose any
duty or obligation on the Guarantee Trustee to perform any act or acts or
exercise any right, power, duty or obligation conferred or imposed on it in any
jurisdiction in which it shall be illegal, or in which the Guarantee Trustee
shall be unqualified or incompetent in accordance with applicable law, to
perform any such act or acts or to exercise any such right, power, duty or
obligation. No permissive power or authority available to the Guarantee Trustee
shall be construed to be a duty to act in accordance with such power and
authority.

     Section 3.3 Indemnity.

     ONEOK agrees to indemnify the Guarantee Trustee (which for purposes of this
Section shall include its officers, directors, employees and agents) for, and to
hold it harmless against, any loss, liability or expense incurred without gross
negligence, willful misconduct or bad faith on the part of the Guarantee
Trustee, arising out of or in connection with the acceptance or administration
of this Guarantee Agreement, including the costs and expenses of defending
itself against any claim or liability in connection with the exercise or
performance of any of its powers or duties hereunder. The Guarantee Trustee will
not claim or exact any lien or charge on any Guarantee Payments as a result of
any amount due to it under this Guarantee Agreement. The indemnification
provided hereunder shall survive the termination of this Guarantee Agreement and
the resignation or removal of the Guarantee Trustee.

     Section 3.4 Expenses.

     ONEOK shall from time to time reimburse the Guarantee Trustee for its
reasonable expenses and costs (including reasonable attorneys' or agents' fees)
incurred in connection with the performance of its duties hereunder to the
extent agreed upon in writing.

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<PAGE>

                          ARTICLE IV GUARANTEE TRUSTEE

     Section 4.1    Guarantee Trustee: Eligibility.

     (a)    There shall at all times be a Guarantee Trustee which shall:

            (i)     not be an Affiliate of ONEOK; and

            (ii)    be a Person that is eligible pursuant to the Trust Indenture
     Act to act as such and has a combined capital and surplus of at least
     $50,000,000, and shall be a corporation meeting the requirements of Section
     310(a) of the Trust Indenture Act. If such corporation publishes reports of
     condition at least annually, pursuant to law or to the requirements of the
     supervising or examining authority, then, for the purposes of this Section
     and to the extent permitted by the Trust Indenture Act, the combined
     capital and surplus of such corporation shall be deemed to be its combined
     capital and surplus as set forth in its most recent report of condition so
     published.

     (b)    If at any time the Guarantee Trustee shall cease to be eligible to
so act under Section 4.1(a), the Guarantee Trustee shall immediately resign in
the manner and with the effect set out in Section 4.2(c).

     (c)    If the Guarantee Trustee has or shall acquire any "conflicting
interest" within the meaning of Section 310(b) of the Trust Indenture Act, the
Guarantee Trustee and ONEOK shall in all respects comply with the provisions of
Section 310(b) of the Trust Indenture Act.

     Section 4.2    Appointment, Removal and Resignation of the Guarantee
Trustee.

     (a)    Subject to Section 4.2(b), the Guarantee Trustee may be appointed or
removed without cause at any time by ONEOK.

     (b)    The Guarantee Trustee shall not be removed until a Successor
Guarantee Trustee has been appointed and has accepted such appointment by
written instrument executed by such Successor Guarantee Trustee and delivered to
ONEOK.

     (c)    The Guarantee Trustee appointed hereunder shall hold office until a
Successor Guarantee Trustee shall have been appointed or until its removal or
resignation. The Guarantee Trustee may resign from office (without need for
prior or subsequent accounting) by an instrument in writing executed by the
Guarantee Trustee and delivered to ONEOK, which resignation shall not take
effect until a Successor Guarantee Trustee has been appointed and has accepted
such appointment by instrument in writing executed by such Successor Guarantee
Trustee and delivered to ONEOK and the resigning Guarantee Trustee.

     (d)    If no Successor Guarantee Trustee shall have been appointed and
accepted appointment as provided in this Section 4.2 within 30 days after
delivery to ONEOK of an instrument of resignation, the resigning Guarantee
Trustee may petition, at the expense of ONEOK, any court of competent
jurisdiction for appointment of a Successor Guarantee Trustee. Such court may
thereupon, after prescribing such notice, if any, as it may deem proper, appoint
a Successor Guarantee Trustee.

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                               ARTICLE V GUARANTEE

     Section 5.1    Guarantee.

     ONEOK irrevocably and unconditionally agrees to pay in full to the Holders
the Guarantee Payments (without duplication of amounts theretofore paid by or on
behalf of the Issuer), as and when due, regardless of any defense, right of
set-off or counterclaim which the Issuer may have or assert. ONEOK's obligation
to make a Guarantee Payment may be satisfied by direct payment of the required
amounts by ONEOK to the Holders or by causing the Issuer to pay such amounts to
the Holders. ONEOK shall give prompt written notice to the Guarantee Trustee in
the event it makes any direct payment hereunder.

     Section 5.2    Waiver of Notice and Demand.

     ONEOK hereby waives notice of acceptance of the Guarantee Agreement and of
any liability to which it applies or may apply, presentment, demand for payment,
any right to require a proceeding first against the Guarantee Trustee, Issuer or
any other Person before proceeding against ONEOK, protest, notice of nonpayment,
notice of dishonor, notice of redemption and all other notices and demands.

     Section 5.3    Obligations Not Affected.

     The obligations, covenants, agreements and duties of ONEOK under this
Guarantee Agreement shall in no way be affected or impaired by reason of the
happening from time to time of any of the following:

     (a)    the release or waiver, by operation of law or otherwise, of the
performance or observance by the Issuer of any express or implied agreement,
covenant, term or condition relating to the Preferred Securities to be performed
or observed by the Issuer;

     (b)    the extension of time for the payment by the Issuer of all or any
portion of the Distributions (other than an extension of time for payment of
Distributions that results from the extension of any interest payment period on
the Notes as provided in the Indenture), Redemption Price, Liquidation
Distribution or any other sums payable under the terms of the Preferred
Securities or the extension of time for the performance of any other obligation
under, arising out of, or in connection with, the Preferred Securities;

     (c)    any failure, omission, delay or lack of diligence on the part of the
Holders or the Guarantee Trustee to enforce, assert or exercise any right,
privilege, power or remedy conferred on the Holders pursuant to the terms of the
Preferred Securities, or any action on the part of the Issuer granting
indulgence or extension of any kind;

     (d)    the voluntary or involuntary liquidation, dissolution, sale of any
collateral, receivership, conservatorship, insolvency, bankruptcy, assignment
for the benefit of creditors, reorganization, arrangement, composition or
readjustment of debt of, or other similar proceedings affecting, the Issuer or
any of the assets of the Issuer;

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     (e)    any invalidity of, or defect or deficiency in, the Preferred
Securities;

     (f)    the settlement or compromise of any obligation guaranteed hereby or
hereby incurred; or

     (g)    any other circumstance whatsoever that might otherwise constitute a
legal or equitable discharge or defense of a guarantor, it being the intent of
this Section 5.3 that the obligations of ONEOK hereunder shall be absolute and
unconditional under any and all circumstances.

There shall be no obligation of the Holders to give notice to, or obtain the
consent of, ONEOK with respect to the happening of any of the foregoing.

     Section 5.4    Rights of Holders.

     ONEOK expressly acknowledges that: (i) this Guarantee Agreement will be
deposited with the Guarantee Trustee to be held for the benefit of the Holders;
(ii) the Guarantee Trustee has the right to enforce this Guarantee Agreement on
behalf of the Holders; (iii) the Holders of a Majority in Liquidation Amount of
the Securities have the right to direct the time, method and place of conducting
any proceeding for any remedy available to the Guarantee Trustee in respect of
this Guarantee Agreement or exercising any trust or power conferred upon the
Guarantee Trustee under this Guarantee Agreement; and (iv) any Holder may
institute a legal proceeding directly against ONEOK to enforce its rights under
this Guarantee Agreement, without first instituting a legal proceeding against
the Guarantee Trustee, the Issuer or any other Person.

     Section 5.5    Guarantee of Payment.

     This Guarantee Agreement creates a guarantee of payment and not of
performance or collection. This Guarantee Agreement will not be discharged
except by payment of the Guarantee Payments in full (without duplication of
amounts theretofore paid by the Issuer) or upon distribution of Notes to Holders
as provided in the Trust Agreement.

     Section 5.6    Subrogation.

     ONEOK shall be subrogated to all (if any) rights of the Holders against the
Issuer in respect of any amounts paid to the Holders by ONEOK under this
Guarantee Agreement and shall have the right to waive payment by the Issuer
pursuant to Section 5.1; provided, however, that ONEOK shall not (except to the
extent required by mandatory provisions of law) be entitled to enforce or
exercise any rights which it may acquire by way of subrogation or any indemnity,
reimbursement or other agreement, in all cases as a result of payment under this
Guarantee Agreement, if, at the time of any such payment, any amounts are due
and unpaid under this Guarantee Agreement. If any amount shall be paid to ONEOK
in violation of the preceding sentence, ONEOK agrees to hold such amount in
trust for the Holders and to pay over such amount to the Holders.

     Section 5.7    Independent Obligations.

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     ONEOK acknowledges that its obligations hereunder are independent of the
obligations of the Issuer with respect to the Preferred Securities and that
ONEOK shall be liable as principal and as debtor hereunder to make Guarantee
Payments pursuant to the terms of this Guarantee Agreement notwithstanding the
occurrence of any event referred to in subsections (a) through (g), inclusive,
of Section 5.3 hereof.

                     ARTICLE VI COVENANTS AND SUBORDINATION

     Section 6.1    Subordination.

The obligations of ONEOK under this Guarantee Agreement will constitute
unsecured obligations of ONEOK and will rank subordinate and junior in right of
payment to all Senior Debt (as defined in the Indenture) of ONEOK except those
made pari passu or subordinate to such obligations expressly by their terms. The
obligations of ONEOK hereunder do not constitute Senior Indebtedness of ONEOK.

     Section 6.2    Pari Passu Guarantees.

     Notwithstanding Section 6.1, the obligations of ONEOK under this Guarantee
Agreement shall rank pari passu with the obligations of ONEOK under any similar
Guarantee Agreements issued by ONEOK on behalf of the holders of preferred
securities issued by any ONEOK Capital Trust (as defined in the Indenture)
unless otherwise specified in the similar Guarantee Agreement.

                            ARTICLE VII TERMINATION

     Section 7.1    Termination.

     This Guarantee Agreement shall terminate and be of no further force and
effect upon (i) full payment of the Redemption Price of all Preferred
Securities, (ii) the distribution of Notes to the Holders in exchange for all of
the Preferred Securities or (iii) full payment of the amounts payable in
accordance with the Trust Agreement upon liquidation of the Issuer.
Notwithstanding the foregoing, this Guarantee Agreement will be reinstated if at
any time any Holder must restore payment of any sums paid with respect to
Preferred Securities or this Guarantee Agreement.

                           ARTICLE VIII MISCELLANEOUS

     Section 8.1    Successors and Assigns.

     All guarantees and agreements contained in this Guarantee Agreement shall
bind the successors, assigns, receivers, conservators, trustees and
representatives of ONEOK and shall inure to the benefit of the Holders of the
Preferred Securities then outstanding. Except in connection with a
consolidation, merger or sale involving ONEOK that is permitted under Article
VIII of the Indenture and pursuant to which the successor or assignee agrees in
writing to perform the Guarantor's obligations hereunder, ONEOK shall not assign
its obligations hereunder, and any purported assignment that is not in
accordance with these provisions shall be void.

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         Section 8.2   Amendments.

         Except with respect to any changes which do not adversely affect the
rights of the Holders in any material respect (in which case no consent of the
Holders will be required), this Guarantee Agreement may only be amended with the
prior approval of the Holders of a Majority in Liquidation Amount of the
Securities. The provisions of the Trust Agreement concerning meetings of the
Holders and voting and consent by the Holders shall apply to the giving of such
approval.

         Section 8.3   Notices.

         Any notice, request or other communication required or permitted to be
given hereunder shall be in writing, duly signed by the party giving such
notice, and delivered, telecopied (confirmed by delivery of the original) or
mailed by first class mail as follows:

         (a)   if given to ONEOK, to the address set forth below or such other
address, facsimile number or to the attention of such other Person as ONEOK may
give notice to the Holders:

               ONEOK, INC.
               100 West Fifth Street
               Tulsa, Oklahoma 74103
               Facsimile No.: (918) ___-____
               Attention: Treasurer

         (b)   if given to the Issuer, in care of the Guarantee Trustee, at the
Issuer's (and the Guarantee Trustee's) respective addresses set forth below or
such other address as the Guarantee Trustee on behalf of the Issuer may give
notice to the Holders:

               ONEOK Capital Trust I

               ____________________
               ____________________
               ____________________

               Attention: _________

               with a copy to:

               ____________________
               ____________________
               ____________________
               ____________________
               Facsimile No.:  (___)-___-____
               Attention: _________

         (c)   if given to the Guarantee Trustee, at the Guarantee Trustee's
address set forth below or such other address as the Guarantee Trustee may give
notice to the Holders:

               ____________________

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               ____________________
               ____________________
               ____________________
               ____________________
               Facsimile No.:  (___)-___-____
               Attention: _________

         (d)   if given to any Holder, at the address set forth on the books and
records of the Issuer.

         All notices hereunder shall be deemed to have been given when received
in person, telecopied with receipt confirmed, or mailed by first class mail,
postage prepaid, except that if a notice or other document is refused delivery
or cannot be delivered because of a changed address of which no notice was
given, such notice or other document shall be deemed to have been delivered on
the date of such refusal or inability to deliver.

         Section 8.4   Benefit.

         This Guarantee Agreement is solely for the benefit of the Holders and
is not separately transferable from the Preferred Securities.

         Section 8.5   Interpretation.

         In this Guarantee Agreement, unless the context otherwise requires:

         (a)   capitalized terms used in this Guarantee Agreement but not
defined in the preamble hereto have the respective meanings assigned to them in
Section 1.1;

         (b)   a term defined anywhere in this Guarantee Agreement has the same
meaning throughout;

         (c)   all references to "the Guarantee Agreement" or "this Guarantee
Agreement," or to any other agreement, are to this Guarantee Agreement, or to
any other agreement, as modified, supplemented or amended from time to time;

         (d)   all references in this Guarantee Agreement to Articles and
Sections are to Articles and Sections of this Guarantee Agreement unless
otherwise specified;

         (e)   a term defined in the Trust Indenture Act has the same meaning
when used in this Guarantee Agreement unless otherwise defined in this Guarantee
Agreement or unless the context otherwise requires;

         (f)   a reference to the singular includes the plural and vice versa;
and

         (g)   the masculine, feminine or neuter genders used herein shall
include the masculine, feminine and neuter genders.

         Section 8.6   Governing Law.

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         THIS GUARANTEE AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED AND
INTERPRETED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD
TO THE CONFLICT OF LAW PRINCIPLES THEREOF.

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         This instrument may be executed in any number of counterparts, each of
which so executed shall be deemed to be an original, but all such counterparts
shall together constitute but one and the same instrument.

         THIS GUARANTEE AGREEMENT is executed as of the day and year first above
written.

                                             ONEOK, INC.


                                             By:________________________________

                                             Name:
                                             Title:

                                             Executed in __________________.



                                             SUNTRUST BANK
                                                 as Guarantee Trustee


                                             By:________________________________
                                             Name:
                                             Title:

                                             Executed in ___________________.

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