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                                                                     EXHIBIT 4.3
                             2000 STOCK OPTION PLAN
                                       OF
                          PENNZOIL-QUAKER STATE COMPANY


1.       PURPOSE OF THE PLAN.

                  This 2000 Stock Option Plan (the "Plan") is intended as an
employment incentive to retain in the employ of Pennzoil-Quaker State Company
(the "Company") and any Subsidiary or Parent of the Company (within the meaning
of Section 424(e) or (f) of the Internal Revenue Code of 1986, as amended (the
"Code"), and including any corporation that becomes a Subsidiary or Parent of
the Company) persons of training, experience and ability, to attract new
employees whose services are considered unusually valuable, to encourage the
sense of proprietorship of such persons, and to stimulate the active interest of
such persons in the development and financial success of the Company. It is
further intended that options issued pursuant to the Plan shall constitute
nonqualified stock options within the meaning of Section 83 of the Code.

2.       ADMINISTRATION OF THE PLAN.

                  The Board of Directors of the Company (the "Board") shall
appoint and maintain a Compensation Committee (hereinafter called the
"Committee") of the Board to administer the Plan, which Committee shall be
constituted to permit the Plan to comply with Rule 16b-3 ("Rule 16b-3")
promulgated under the Securities Exchange Act of 1934 ("Exchange Act") and who
shall serve at the pleasure of the Board. No member of such Committee shall be
eligible to receive nonqualified stock options under the Plan ("Options") or
any other plan of the Company or its affiliates which entitles participants to
acquire stock, stock appreciation rights, or stock options of the Company or
its affiliates while serving on the Committee. The Options granted under this
Plan shall be nonqualified stock options within the meaning of Section 83 of
the Code. All decisions and selections made by the Committee pursuant to the
provisions of the Plan shall be made by a majority of its members. Any
decision reduced to writing and signed by all of the members shall be fully
effective as if it had been made by a majority at a meeting duly held. Members
of the Committee may participate in a meeting by means of conference telephone
or similar communications equipment by means of which all persons
participating in the meeting can hear each other. The Committee shall have
full power and authority to designate participants, to determine the terms and
provisions of respective option agreements (which need not be identical), and
to interpret the provisions and supervise the administration of the Plan. The
Committee shall have the authority, exercisable in its sole discretion, to
grant various forms of Options containing such terms and conditions,
consistent with the provisions of this Plan, as the Committee shall determine,
including the authority to grant in its discretion to the holder of an
outstanding Option, in exchange for the surrender and cancellation of such
Option, a new Option having a purchase price lower than that provided in the
Option so surrendered and cancelled and containing such other terms and
conditions as the Committee may prescribe in accordance with the provisions of
the Plan, except that shares subject to purchase pursuant to any Option or
portion thereof relinquished and not required to be issued upon such
relinquishment shall not again be available for Options under the Plan.

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3.       DESIGNATIONS OF PARTICIPANTS.

                  The persons eligible for participation in the Plan as
recipients of Options shall include all employees of the Company or of any
Subsidiary or Parent of the Company including key employees of any corporation
that becomes a Subsidiary or Parent after the date that this Plan is adopted. An
employee who has been granted an Option hereunder may be granted an additional
Option or Options, if the Committee shall so determine.

4.       STOCK RESERVED FOR THE PLAN.

                  Subject to adjustments provided in Paragraph 9 hereof, a total
of 3,200,000 shares of Common Stock, $0.10 par value, of the Company ("Stock")
shall be subject to the Plan. The shares subject to the Plan shall consist of
unissued shares or previously issued shares reacquired and held by the Company,
or any Subsidiary or Parent of the Company, and such amount of shares shall be
and hereby is reserved for sale for such purpose. Any of such shares which may
remain unsold and which are not subject to outstanding Options at the
termination of the Plan shall cease to be reserved for the purpose of the Plan,
but until termination of the Plan the Company shall at all times reserve a
sufficient number of shares to meet the requirements of the Plan. Should any
Option expire or be cancelled prior to its exercise or relinquishment in full,
the shares theretofore subject to such Option may again be subjected to an
Option under the Plan, except that shares subject to purchase pursuant to any
Option or portion thereof relinquished and not required to be issued upon such
relinquishment shall not again be available for Options under the Plan.

5.       OPTION PRICE.

                  (a) The purchase price of each share placed under an Option
         pursuant to the Plan shall be determined by the Committee, but in no
         event shall be less than 100% of the Fair Market Value of such share on
         the date the Option is granted.

                  (b) "Fair Market Value" of a share of Stock means, as of a
         particular date, (i) if shares of Stock are listed on a national
         securities exchange, the mean between the highest and lowest sales
         price per share of Stock reported on the consolidated transaction
         reporting system for the principal national securities exchange on
         which shares of Stock are listed on that date, or, if there shall have
         been no such sale so reported on that date, on the last preceding date
         on which such a sale was so reported, (ii) if shares of Stock are not
         so listed but are quoted on the Nasdaq National Market, the mean
         between the highest and lowest sales price per share of Stock reported
         by the Nasdaq National Market on that date, or, if there shall have
         been no such sale so reported on that date, on the last preceding date
         on which such a sale was so reported, (iii) if the Stock is not so
         listed or quoted, the mean between the closing bid and asked price on
         that date, or, if there are no quotations available for such date, on
         the last preceding date on which such quotations are available, as
         reported by the Nasdaq Stock Market, or, if not reported by the Nasdaq
         Stock Market, by the National Quotation Bureau Incorporated or (iv) if
         shares of Stock


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         are not publicly traded, the most recent value determined by an
         independent appraiser appointed by the Company for such purpose.

6.       OPTION PERIOD.

                  (a) The Options granted under this Plan shall be for a term of
         not more than ten years from the date of granting of each Option.

                  (b) If the Company is reorganized or merged or consolidated
         with another corporation while unexercised Options remain outstanding
         under the Plan, there shall be substituted for the shares subject to
         the unexercised portions of such outstanding Options an appropriate
         number of shares of each class of stock or other securities of the
         reorganized or merged or consolidated corporation distributed to the
         holders of Stock in respect of their shares; provided, however, that
         all such Options may be cancelled by the Company as of the effective
         date of any such reorganization, merger, or consolidation or of any
         dissolution or liquidation of the Company by giving notice of its
         intention to do so to each holder thereof or his personal
         representative and by permitting the purchase during a period of not
         less than 30 days next preceding such effective date of all of the
         shares subject to such outstanding Options.

7.       EXERCISE OF OPTIONS.

                  (a) The Committee, in granting Options hereunder, shall have
         discretion to determine the terms upon which such Options shall be
         exercisable, subject to the applicable provisions of this Plan. In any
         event, Options shall be exercisable only after 12 months of continued
         employment with the Company or any Subsidiary or Parent of the Company
         immediately following the date upon which the Option is granted, and no
         Option may thereafter become exercisable for a number of shares
         exceeding (i) 33-1/3% of the number of shares subject to the Option
         until after two years of such continued employment, or (ii) 66-2/3% of
         the number of shares subject to the Option until after three years of
         such continued employment; provided, however, that an Option, if the
         Option Agreement so provides, may be exercised irrespective of the
         above-described 12-month, 33-1/3%, and 66-2/3% limitations in the event
         of:

                           (A) Death of the optionee while in the employment of
                  the Company or any Subsidiary or Parent of the Company;

                           (B) Termination of employment of the optionee by
                  reason of disability, as determined by the Committee; or

                           (C) Termination of the optionee's employment by
                  reason of retirement under or in accordance with the
                  retirement plan of the Company or any Subsidiary or Parent of
                  the Company, in which he is then participating after
                  completion, as of the date of such retirement, of not less
                  than five years' employment with the Company or any Subsidiary
                  or Parent of the Company,


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                  or termination of employment for such other reasons as may
                  be approved in writing by the Committee.

                  (b) Options may be exercised solely by the optionee during his
         lifetime or after his death by the personal representative of the
         optionee's estate or the person or persons entitled thereto under his
         will or under the laws of descent and distribution.

                  (c) The purchase price of the shares for which an Option is
         exercised shall be paid in full at the time of the exercise. Such
         purchase price shall be payable in cash, or at the option of the holder
         of such Option, in Stock theretofore owned by such holder (or in a
         combination of cash and such Stock). For purposes of determining the
         amount, if any, of the purchase price satisfied by payment in Stock,
         such Stock shall be valued at its Fair Market Value on the date of
         exercise in accordance with subparagraph (b) of Paragraph 5. Any Stock
         delivered in satisfaction of all or a portion of the purchase price
         shall be appropriately endorsed for transfer and assignment to the
         Company. No holder of an Option shall be, or have any of the rights or
         privileges of, a shareholder of the Company in respect of any shares
         purchasable upon the exercise of any part of an Option unless and until
         certificates representing such shares shall have been issued by the
         Company to such holder.

8.       RELINQUISHMENT OF OPTIONS; ASSIGNABILITY.

                  (a) The Committee, in granting Options hereunder, shall have
         discretion to determine whether or not certain Options shall include a
         right of relinquishment as hereinafter provided by this Paragraph 8.
         The Committee shall also have discretion to determine whether an option
         agreement evidencing an Option granted by the Committee shall be
         amended or supplemented to include such a right of relinquishment.
         Neither the Committee nor the Company shall be under any obligation or
         incur any liability to any person by reason of the Committee's refusing
         to grant or include a right of relinquishment in any Option granted
         hereunder or in any option agreement evidencing the same. Subject to
         the Committee's determining in any case that the grant by it of a right
         of relinquishment is consistent with Paragraph 1 hereof, any Option
         granted under the Plan and the option agreement evidencing such Option,
         may provide:

                           (i) That the optionee, or his heirs or other legal
                  representatives to the extent entitled to exercise the Option
                  under the terms thereof, in lieu of purchasing the entire
                  number of shares subject to purchase thereunder, shall have
                  the right to relinquish all or any part of the unexercised
                  portion of the Option (to the extent exercisable as provided
                  in (iv), hereinbelow) for a number of shares of Stock and an
                  amount of cash to be determined as follows:

                                    (A) The written notice of exercise of such
                           right of relinquishment, provided for in clause (ii)
                           of this subparagraph (a), shall state the percentage,
                           if any, of the Appreciated Value, hereinafter
                           defined, which such optionee elects to receive in
                           cash (which percentage is called the "Cash
                           Percentage"), such Cash Percentage to be in
                           increments of ten


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                           percent (10%) of such Appreciated Value up to (but
                           not to exceed) fifty percent (50%) thereof;

                                    (B) The number of shares of Stock issuable
                           pursuant to such relinquishment shall be the number
                           of such shares, rounded to the next greater number of
                           full shares, as shall be equal to: one hundred
                           percent (100%) less the Cash Percentage, times the
                           excess of (1) the aggregate current market value of
                           the shares of such Stock covered by the Option or the
                           portion thereof so relinquished over (2) the
                           aggregate purchase price for such shares specified in
                           such Option (which excess is called the "Appreciated
                           Value"), divided by the then current market value per
                           share of such Stock; and

                                    (C) The amount of cash payable pursuant to
                           such relinquishment shall be an amount equal to the
                           Appreciated Value less the aggregate current market
                           value of the issued shares, which cash shall be paid
                           by the Company subject to such conditions as are
                           deemed advisable by the Committee to permit
                           compliance by the Company with the withholding
                           provisions applicable to employers, including
                           withholding under the Code and applicable state law;

                           (ii) That such right of relinquishment may be
                  exercised only upon receipt by the Company of a written notice
                  of such relinquishment which shall be dated the date of
                  election to make such relinquishment; and that, for the
                  purposes of the Plan, such date of election shall be deemed to
                  be the date when such notice is sent by registered or
                  certified mail, if by mail, or when receipt is acknowledged by
                  the Company, if mailed by other than registered or certified
                  mail, or if delivered by hand or by any telegraphic
                  communications equipment of the sender or otherwise delivered,
                  provided that, in the event the method just described for
                  determining such date of election shall not be or remain
                  consistent with provisions of Rule 16b-3, which exempts from
                  the operation of Section 16(b) of the Exchange Act in whole or
                  in part any such relinquishment transaction, then such date of
                  election shall be determined by such other method consistent
                  with Section 16(b) or such rules or regulations as the
                  Committee shall in its discretion select and apply;

                           (iii) That the "current market value" of a share of
                  Stock shall be its Fair Market Value on the day on which
                  written notice of relinquishment is received by the Company in
                  accordance with subparagraph (b) of Paragraph 5; and

                           (iv) That the Option, or any portion thereof, may be
                  relinquished only to the extent that (A) it is exercisable on
                  the date written notice of relinquishment is received by the
                  Company, and (B) the Committee, subject to the provisions of
                  subparagraph (b) of this Paragraph 8 shall consent to the
                  election of the holder of such Option to relinquish such
                  Option as set forth in such written notice of relinquishment,
                  and (C) the holder of such Option pays, or makes provision


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                  satisfactory to the Company for payment of, any taxes which
                  the Company is obligated to collect with respect to such
                  relinquishment.

                  (b) The Committee shall have sole discretion to consent to or
         disapprove any election of a holder of an Option to relinquish such
         Option for Stock and cash as provided in subparagraph (a) of this
         Paragraph 8, provided that the Committee shall, in the exercise of such
         discretion, be subject to such limitations as may be imposed on the
         administrators of a plan (such as the Committee) by Rule 16b-3, and as
         the same may be hereafter further amended, as a condition to the
         exemption from the operation of Section 16(b) of transactions involving
         solely the surrender and cancellation of stock options in conjunction
         with the exercise and cancellation of a stock appreciation right issued
         pursuant to a plan and the receipt of cash awarded in connection with a
         stock appreciation right. Neither the Committee nor the Company shall
         be under any liability to any person by reason of the Committee's
         disapproval of any election pursuant to this subparagraph (b).

                  (c) The Committee, in granting Options hereunder, shall have
         discretion to determine the terms upon which such Options shall be
         relinquishable, subject to the applicable provisions of the Plan and
         including such provisions as deemed advisable to permit the exemption
         from the operation of Section 16(b) of the Exchange Act in whole or in
         part of any such transaction involving such relinquishment, and Options
         outstanding, and option agreements evidencing such Option, may be
         amended, if necessary, to permit such exemption.

                  (d) Neither any Option nor any right to relinquish the same to
         the Company as contemplated by this Paragraph 8 shall be assignable or
         otherwise transferable except by will or the laws of descent and
         distribution.

9.       CAPITAL CHANGE OF THE COMPANY.

                  If the outstanding shares of Stock of the Company shall at any
time be changed or exchanged by declarations of a stock dividend, split-up,
combination of shares, or recapitalization, the number and kind of shares
subject to this Plan or subject to any Options theretofore granted, and the
Option prices, shall be appropriately and equitably adjusted so as to maintain
the proportionate number of shares without changing the aggregate Option price;
provided, however, no adjustment shall be made by reason of the distribution of
subscription rights on outstanding stock.

10.      PURCHASE FOR INVESTMENT.

                  Whether or not the Options and shares covered by the Plan have
been registered under the Securities Act of 1933, as amended, each person
exercising an Option under the Plan may be required by the Company to give a
representation in writing that he is acquiring such shares for his own account
for investment and not with a view to, or for sale in connection with, the
distribution of any part thereof.


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11.      TAX WITHHOLDING.

                  The Company shall have the right to deduct applicable taxes
from any Option or relinquishment payment and withhold, at the time of delivery
of shares of Stock under this Plan, an appropriate number of shares of Stock for
payment of taxes required by law or to take such other action as may be
necessary in the opinion of the Company to satisfy all obligations for
withholding of such taxes. The Committee may also permit withholding to be
satisfied by the transfer to the Company of shares of Stock theretofore owned by
the holder of the Option with respect to which withholding is required. If
shares of Stock are used to satisfy tax withholding, such shares shall be valued
based on the Fair Market Value when the tax withholding is required to be made.

12.      EFFECTIVE DATE OF PLAN.

                  The Plan shall be effective March 9, 2000. No Option shall be
granted pursuant to the Plan after March 8, 2010.

13.      AMENDMENT, MODIFICATION, SUSPENSION OR TERMINATION.

                  The Board may amend, modify, suspend or terminate this Plan at
any time for the purpose of meeting or addressing any changes in legal
requirements or for any other purpose permitted by law except that (i) no
amendment or alteration that would impair the rights of any optionee under any
Option previously granted to such optionee shall be made without such optionee's
consent and (ii) no amendment or alteration shall be effective prior to approval
by the Company's stockholders to the extent such approval is then required
pursuant to Rule 16b-3 in order to preserve the applicability of any exemption
provided by such rule to any Option then outstanding (unless the holder of such
Option consents) or to the extent stockholder approval is otherwise required by
applicable legal requirements.

14.      GOVERNMENT REGULATIONS.

                  The Plan, and the granting and exercise of Options thereunder,
and the obligation of the Company to sell and deliver shares under such Options,
shall be subject to all applicable laws, rules and regulations, and to such
approvals by any governmental agencies or national securities exchanges as may
be required.


                                                 PENNZOIL-QUAKER STATE COMPANY


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