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                                                                 EXHIBIT 99.4(b)

                          PENNZOIL-QUAKER STATE COMPANY
                         THRIFT AND STOCK PURCHASE PLAN

               (As Amended and Restated Effective January 1, 1997)

                                Second Amendment


         Pennzoil-Quaker State Company, a Delaware corporation (the "Company"),
having assumed sponsorship of the Quaker State Corporation Thrift and Stock
Purchase Plan, as amended and restated, effective January 1, 1997, which plan
was merged with the Quaker State Employee Stock Ownership Plan, effective
January 1, 1998 and renamed the Pennzoil-Quaker State Company Thrift and Stock
Purchase Plan, effective December 31, 1998 (the "Plan"), and having reserved the
right under Section 11.01 thereof to amend the Plan, does hereby amend the Plan,
effective as of January 1, 2000 to read as follows:

         1. The last paragraph of Section 3.01 of the Plan is hereby amended by
adding a sentence thereto to read as follows:

         "Notwithstanding anything herein to the contrary, from and after
     January 1, 2000, only those Employees employed by Blue Coral, Inc., or by
     one of the Company's Canadian subsidiaries, including Quaker State, Inc.
     and Valley Camp, Inc., shall be eligible to make contributions to this
     Plan."

         2. Section 6.02 of the Plan is hereby amended by deleting the last
sentence therein and adding a sentence thereto to read as follows:

         "From and after January 1, 2000, each Participant who has attained age
     55 may direct that full shares of common stock of the Company held in his
     or her Company Matching Contribution Account, Profit Sharing Account, Tye
     Profit Sharing Account and ESOP Account be liquidated and the proceeds
     invested among the funds in Fund A Group as provided in Section 6.01."




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         3. The second subsection (b) under Section 8.06 of the Plan shall be
amended in its entirety to read as follows:

         "(b) The Participant has obtained all distributions and all nontaxable
     (at the time of the loan) loans currently available under all plans
     maintained by the Company provided, however, that the Participant must
     request and receive a hardship withdrawal under this Plan, prior to
     requesting a hardship withdrawal under the Pennzoil-Quaker State Savings
     and Investment Plan;"

         4. The last paragraph of Section 8.07 is hereby amended in its
entirety, to read as follows:

         "From and after January 1, 2000, a Participant may not initiate a loan
     more than once every six months; may not have more than one loan
     outstanding at a time under this Plan and may not refinance an outstanding
     loan. If on January 1, 2000 a Participant has one or more outstanding loans
     under this Plan, such Participant may not make application for a loan until
     all outstanding loans are repaid in full."

         5. Section 20.03 of the Plan is hereby amended in its entirety to read
as follows:

         "Qualified Participant's Diversification Election. From and after
     January 1, 2000, a Participant who has attained age 55 shall be referred to
     as a "Qualified Participant" and shall be eligible to direct the
     diversification of his or her ESOP Contribution Account as provided in
     Section 6.02 of the Plan."

         IN WITNESS WHEREOF, Pennzoil-Quaker State Company has caused these
presents to be executed by its duly authorized officers in a number of copies,
all of which shall constitute one and the same instrument, which may be
sufficiently evidenced by any executed copy thereof, this 14th day of December,
1999, but effective as herein provided.

                                                  PENNZOIL-QUAKER STATE COMPANY


                                                  By: /s/ RAYMOND T. FISCHER
                                                      --------------------------
                                                      Raymond T. Fischer
                                                      Agent and Attorney-in-Fact


ATTEST:



/s/ LINDA F. CONDIT
-------------------
Secretary

[SEAL]


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