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                                                                    EXHIBIT 3.15


                         Certificate Of Incorporation

                                      Of

                Pennzoil-Quaker State International Corporation



                                   Article I

      The name of the corporation is Pennzoil-Quaker State International
Corporation.


                                  Article II

     The address of its registered office in the State of Delaware is
Corporation Trust Center, 1209 Orange Street, in the City of Wilmington, County
of New Castle.  The name of its registered agent at such address is The
Corporation Trust Company.


                                  Article III

     The nature of the business or purposes to be conducted or promoted by the
corporation is to engage in any lawful business, act or activity for which
corporations may be organized under the General Corporation Law of Delaware.


                                  Article IV

     The total number of shares of stock which the corporation shall have
authority to issue is one thousand (1,000) shares of Common Stock, of the par
value of $1.00 per share (Common Stock).  Each share of Common Stock shall
entitle the holder thereof to one vote at all meetings of the stockholders of
the corporation.  Shares of such stock may be issued for such consideration and
for such corporate purposes as the Board of Directors may from time to time
determine.


                                   Article V

     The name and mailing address of the incorporator signing the articles of
incorporation
is:

                Name                Address
                ----                -------

                Linda F. Condit     P. O. Box 2967
                                    Houston, Texas 77252-2967
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                                  Article VI

     In furtherance of, and not in limitation of, the powers conferred by
statute, the Board of Directors is expressly authorized to make, alter or repeal
the by-laws of the corporation.


                                  Article VII

     No contract or other transaction between the corporation and any other
corporation and no other act of the corporation with relation to any other
corporation shall, in the absence of fraud, in any way be invalidated or
otherwise affected by the fact that any one or more of the directors of the
corporation are pecuniarily or otherwise interested in, or are directors or
officers of, such other corporation.  Any director of the corporation
individually, or any firm or association of which any director may be a member,
may be a party to, or may be pecuniarily or otherwise interested in, any
contract or transaction of the corporation, provided that the fact that he
individually or as a member of such firm or association is such a party or so
interested shall be disclosed or shall have been known to the Board of Directors
or a majority of such members thereof as shall be present at any meeting of the
Board of Directors at which action upon any such contract or transaction shall
be taken; any director of the corporation who is also a director or officer of
such other corporation or who is such a party or so interested may be counted in
determining the existence of a quorum at any meeting of the Board of Directors
which shall authorize any such contract or transaction, and may vote thereat to
authorize any such contract or transaction, with like force and effect as if he
were not such director or officer of such other corporation or not so
interested.  Any director of the corporation may vote upon any contract or other
transaction between the corporation and any subsidiary or affiliated corporation
without regard to the fact that he is also a director of such subsidiary or
affiliated corporation.


                                 Article VIII

     The corporation shall have the right, subject to any express provisions or
restrictions contained in the certificate of incorporation or by-laws, from time
to time to amend the certificate of incorporation or any provisions thereof in
any manner now or hereafter provided by law, and all rights and powers at any
time conferred upon the directors or stockholders of the corporation by the
certificate of incorporation or any amendment thereof are subject to such right
of the corporation

     I, the undersigned, being the incorporator hereinbefore named, for the
purpose of forming a corporation pursuant to the General Corporation Law of the
State of Delaware, do make this certificate, hereby declaring that this is my
act and deed and that the facts herein stated are true and accordingly have
hereunto set my hand this 20th day of September, 1999.

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                                    /s/ Linda F. Condit
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                                    Linda F. Condit

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