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                                                                    EXHIBIT 10.8

                          PENNZOIL-QUAKER STATE COMPANY
                        SUPPLEMENTAL LIFE INSURANCE PLAN


I. PURPOSES OF PLAN, DEFINITIONS AND DURATION.

         1.1 Purposes. This Supplemental Life Insurance Plan (the "Plan") of
Pennzoil-Quaker State Company (the "Company") for selected executives is
intended to attract and retain executives of outstanding competence and ability
by providing financial security to them and their surviving spouse or other
beneficiaries.

         1.2 Definitions.

                  (a) "Company" means Pennzoil-Quaker State Company or any
         successor.

                  (b) "Subsidiary" means any corporation in which the Company
         owns, directly or indirectly, stock possessing 50% or more of the total
         combined voting power of all classes of stock or any affiliated company
         which is controlled by the Company by reason of a management contract
         and stock ownership.

                  (c) "Board" means the Board of Directors of the Company.

                  (d) "Closing Date" means the date of Closing described in
         Agreement and Plan of Merger, dated as of April 14, 1998, among
         Pennzoil Company, Pennzoil Products Company, Downstream Merger Company
         and Quaker State Corporation ("Merger Agreement").

                  (e) "Employee" means any person, including an officer of the
         Company or any Subsidiary (whether or not he is also a director
         thereof), who, at the time such person is designated a Participant
         hereunder, is employed by the Company or any Subsidiary on a full-time
         basis, who is compensated for such employment by a regular salary and
         who, in the opinion of the Committee, is one of the officers or other
         key executives of the Company or any Subsidiary in a position to
         contribute materially to the continued growth and development and to
         the future financial success of the Company.

                  (f) "Participant" means an Employee who has been designated by
         the Committee to participate in the Plan. [THE TERM PARTICIPANT ALSO
         MEANS ANY INDIVIDUAL WHO, IMMEDIATELY PRIOR TO THE "DISTRIBUTION DATE,"
         AS DEFINED IN THE MERGER AGREEMENT, WAS A PARTICIPANT IN THE
         PENNZENERGY COMPANY SUPPLEMENTAL LIFE INSURANCE PLAN 


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         (FORMERLY, THE PENNZOIL COMPANY SUPPLEMENTAL LIFE INSURANCE PLAN) AND
         WOULD HAVE BECOME AN EMPLOYEE BUT FOR THE FACT THAT SUCH INDIVIDUAL HAD
         A "TOTAL AND PERMANENT DISABILITY," AS DEFINED IN THE PENNZENERGY
         COMPANY SUPPLEMENTAL DISABILITY PLAN (FORMERLY, THE PENNZOIL COMPANY
         SUPPLEMENTAL DISABILITY PLAN.]

                  (g) "Retirement Plan" means the Pennzoil-Quaker State Company
         Salaried Employees Retirement Plan.

                  (h) "Normal Retirement Date" means the normal retirement date
         under the Retirement Plan.

         1.3 Term. The effective date of the Plan is the Closing Date. The Plan
shall continue until terminated by the Board as herein provided.

II. ADMINISTRATION OF THE PLAN - COMMITTEE.

         2.1 Appointment of Committee. The Plan shall be administered by the
Compensation Committee or such other committee of the Board as may be designated
by the Board from time to time (the "Committee").

         2.2 Committee Powers. The Committee shall be deemed to have and to be
exercising all of the powers of the Board in the performance of any of the
powers and duties delegated to it under the Plan, including, but without
limiting the generality of the foregoing, the selection of Participants. The
Committee may from time to time establish rules for the administration of the
Plan which are not inconsistent with the provisions and purposes of the Plan.

         2.3 Committee Action. A majority of the members of the Committee shall
constitute a quorum for the transaction of business. All action taken by the
Committee at a meeting shall be by the vote of a majority of those present at
such meeting, but any action may be taken by the Committee without a meeting
upon written consent signed by all of the members of the Committee. 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.

         2.4 Committee Determinations Conclusive. The determination of the
Committee as to any disputed question of construction or interpretation arising
under the Plan shall be final, binding, and conclusive upon all persons.

III. ELIGIBILITY.

         3.1 Eligibility Requirements. The Committee may from time to time
establish eligibility requirements for Employees to participate in the Plan.



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         3.2 Designation of Participants. From time to time during the
continuation of the Plan, the Committee may designate one or more eligible
Employees to participate in the Plan and shall advise each such Employee of his
selection.

IV. SUPPLEMENTAL LIFE INSURANCE PAYMENTS.

         4.1 Amount of Coverage. The Company will pay the premiums on
supplemental life insurance coverage on the life of each Participant in an
amount equal to two times the annual salary as in effect from time to time, and
adjusted automatically to coincide with increases in annual salary of the
Participant less the maximum amount of coverage available to the Employee under
the Company's group life insurance plan. This coverage will be continued until
the earlier of the Participant's Normal Retirement Date or termination of
employment of the Participant.

         4.2 Rights of Participants in Supplemental Life Insurance. Each
Participant shall have the right to designate the Beneficiary or Beneficiaries
under each of the life insurance policies on his life issued pursuant to the
terms of this Plan and may assign any and all rights he or she may have in the
Plan. Upon the retirement or other termination of employment of a Participant,
the coverage provided under this Plan shall automatically be terminated and the
Participant shall have no right to continued coverage under this Plan and shall
have no right to any insurance policies issued pursuant to this Plan unless
otherwise required by law; provided, however, that the Company may, in its
discretion, continue paying premiums on all or a portion of any insurance
coverage provided pursuant to this Plan notwithstanding that the Participant's
employment has terminated and may in its discretion convey to the Participant,
or if the Participant has assigned the policy to such Participant's assignee,
all rights of ownership in any policies issued under this Plan on such
Participant's life to the Participant.

         4.3 Withholding of Taxes. The Company shall deduct from the amount of
all benefits paid to Beneficiaries under the Plan any taxes required to be
withheld by the Federal or any state or local government.

V. RIGHTS OF PARTICIPANTS.

         5.1 Limitation of Rights. Nothing in this Plan shall be construed to:

                  (a) Give any Employee of the Company or a Subsidiary any right
         to participate in this Plan; or

                  (b) Limit in any way the right of the Company or any
         Subsidiary to terminate a Participant's employment with the Company or
         any Subsidiary at any time; or

                  (c) Give a Participant or any Beneficiary of a deceased
         Participant any interest in any fund or in any specific asset or assets
         of the Company or any Subsidiary; or


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                  (d) Be evidence of any agreement or understanding, express or
         implied, that the Company or any Subsidiary will employ a Participant
         in any particular position or at any particular rate of remuneration.

         5.2 Assignment of Rights in the Plan. A Participant may assign any and
all rights he or she may have in the Plan.

         5.3 Prerequisites to Benefits. No Beneficiary shall have any right or
interest in the Plan, or any benefits hereunder, unless and until all the terms,
conditions and provisions of the Plan which affect such Beneficiary or the
deceased Participant shall have been complied with as specified herein.

VI. MISCELLANEOUS.

         6.1 Amendment or Termination of the Plan. The Board may amend or
terminate this Plan at any time. Any such amendment or termination shall not,
however, affect the rights of the Beneficiary of any deceased Participant to the
benefits provided hereunder.

         6.2 Reliance upon Information. The Board and the Committee shall not be
liable for any decision or action taken in good faith in connection with the
administration of this Plan. Without limiting the generality of the foregoing,
any such decision or action taken by the Board or the Committee in reliance upon
any information supplied to them by an officer of the Company, the Company's
legal counsel or by the Company's independent accountants in connection with the
administration of this Plan shall be deemed to have been taken in good faith.

         6.3 Applicable Laws. This Plan shall be construed, administered and
governed in all respects under the laws of the State of Texas.

                                                   PENNZOIL-QUAKER STATE COMPANY




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