EXHIBIT 99.5
 
   OFFER TO EXCHANGE NEWLY ISSUED          OFFER TO EXCHANGE NEWLY ISSUED
                                            
4.90% EXCHANGEABLE SENIOR DEBENTURES    4.95% EXCHANGEABLE SENIOR DEBENTURES
            DUE 2008                                DUE 2008     
 
 
                 OF                                      OF
 
 
          PENNZOIL COMPANY                        PENNZOIL COMPANY
 
 
    FOR A PORTION OF OUTSTANDING            FOR A PORTION OF OUTSTANDING
 
 
     6 1/2% EXCHANGEABLE SENIOR              4 3/4% EXCHANGEABLE SENIOR
         DEBENTURES DUE 2003                     DEBENTURES DUE 2003
 
 
 
To Our Clients:
   
  Enclosed for your consideration is a Prospectus, dated July 1, 1998 (the
"Prospectus"), of Pennzoil Company, a Delaware corporation (the "Company"), and
related Letters of Transmittal (which, together with the Prospectus,
constitutes the "Exchange Offers") relating to the offer by the Company to
issue its new 4.90% exchangeable senior debentures due 2008 (the "New 4.90%
Debentures") in exchange for a portion of its outstanding 6 1/2% exchangeable
senior debentures due 2003 (the "6 1/2% Debentures") and the offer by the
Company to issue its new 4.95% exchangeable senior debentures due 2008 (the
"New 4.95% Debentures) in exchange for a portion of its outstanding 4 3/4%
exchangeable senior debentures due 2003 (the "4 3/4% Debentures" and, together
with the 6 1/2% Debentures, the "Old Debentures") of the Company, upon the
terms and subject to the conditions set forth in the Prospectus. This material
is being forwarded to you as the beneficial owner of the Old Debentures held by
us in your account but not registered in your name.     
   
  The 6 1/2% Exchange Offer will be for a principal amount of 6 1/2% Debentures
(the "6 1/2% Target Amount") that is exchangeable into between 4.76 million and
6.00 million shares of common stock of Chevron Corporation under the existing
exchange rights, and upon the terms and conditions set forth in the Prospectus
and the related 6 1/2% Letter of Transmittal (which, together with the
Prospectus, constitutes the "4 3/4% Exchange Offer"). The New 4.90% Debentures
will not be issued in denominations of less than $1,000, and the Company will
pay cash in lieu of issuing New 4.90% Debentures in principal amounts of less
than $1,000.     
   
  The 4 3/4% Exchange Offer will be for a principal amount of 4 3/4% Debentures
(the "4 3/4% Target Amount") that is exchangeable into between 3.40 million and
4.29 million shares of Chevron Stock under existing exchange rights, and upon
the terms and conditions set forth in the Prospectus and the related 4 3/4%
Letter of Transmittal (which, together with the Prospectus, constitutes the "4
3/4% Exchange Offer"). The New 4.95% Debentures will not be issued in
denominations of less than $1,000, and the Company will pay cash in lieu of
issuing New 4.95% Debentures in a principal amount of less than $1,000.     
   
  PLEASE NOTE THAT THE EXCHANGE OFFERS WILL EXPIRE AT 5:00 P.M., NEW YORK CITY
TIME, ON FRIDAY, JULY 31, 1998, UNLESS EXTENDED BY THE COMPANY, IN WHICH CASE
THE TERM "6 1/2% EXPIRATION DATE" MEANS THE LATEST DATE AND TIME TO WHICH THE 6
1/2% EXCHANGE OFFER IS EXTENDED, AND THE TERM "4 3/4% EXPIRATION DATE" MEANS
THE LATEST DATE AND TIME TO WHICH THE 4 3/4% EXCHANGE OFFER IS EXTENDED.     
   
  The Company expressly reserves the right to withdraw or terminate either or
both of the Exchange Offers and promptly return all Old Debentures, at any
time, (a) if either or both of the Exchange Offers would result in less than
$100 million in principal amount of the respective series of New Debentures
being issued or upon the failure of certain other conditions described in the
Prospectus (b) if the Average Chevron Stock Price is less than $76.00 per share
or is more than $89.00 per share or (c) upon the occurrence of any of the other
events listed in the Prospectus.     

 
  We are the holder of record of Old Debentures held by us for your account. A
tender of such Old Debentures can be made only by us as the record holder and
pursuant to your instructions. THE LETTERS OF TRANSMITTAL ARE FURNISHED TO YOU
FOR YOUR INFORMATION ONLY AND CANNOT BE USED BY YOU TO TENDER THE OLD
DEBENTURES HELD BY US FOR YOUR ACCOUNT.
 
  We request instructions as to whether you wish to tender any or all of the
Old Debentures held by us for your account pursuant to the terms and
conditions of either or both of the Exchange Offers. Please so instruct us by
completing, executing, detaching, and returning to us the instruction form on
the detachable part hereof. An envelope to return your instructions to us is
enclosed. If you authorize tender of your Old Debentures, please forward to us
your instructions in ample time to permit us to submit a tender on your behalf
prior to either or both of the Expiration Dates. Unless otherwise indicated on
the instruction form, you will be deemed to have tendered the entire aggregate
principal amount at maturity of Old Debentures held by us for your account.
 
                                          Very truly yours,
 
 
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                       INSTRUCTIONS WITH RESPECT TO THE
 
   OFFER TO EXCHANGE NEWLY ISSUED           OFFER TO EXCHANGE NEWLY ISSUED
 
 
4.90% EXCHANGEABLE SENIOR DEBENTURES     4.95% EXCHANGEABLE SENIOR DEBENTURES
              DUE 2008                                 DUE 2008
 
 
                 OF                                       OF
 
 
          PENNZOIL COMPANY                         PENNZOIL COMPANY
 
 
    FOR A PORTION OF OUTSTANDING             FOR A PORTION OF OUTSTANDING
 
 
     6 1/2% EXCHANGEABLE SENIOR               4 3/4% EXCHANGEABLE SENIOR
         DEBENTURES DUE 2003                      DEBENTURES DUE 2003
 
 
 
  The undersigned acknowledges receipt of your letter enclosing the
Prospectus, dated July 1, 1997, of Pennzoil and the related Letters of
Transmittal relating to the respective Exchange Offers. This will instruct you
to tender the principal amount at maturity of Old Debentures indicated below
held by you for the account of the undersigned, pursuant to the terms and
subject to the conditions of the respective Exchange Offers, and confirm that
you may make the representations contained in the respective Letters of
Transmittal on behalf of the undersigned.
 
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                 DESCRIPTION OF OLD DEBENTURES TO BE TENDERED
 
- -------------------------------------------------------------------------------
 
- -------------------------------------------------------------------------------
 
Aggregate Principal                                      Aggregate Principal
       Amount                                                  Amount
     of 6 1/2%                                          of 6 1/2% Debentures
     Debentures                                               Tendered
Held by You for the
      Account
 of the Undersigned
 
- -------------------------------------------------------------------------------
 
- -------------------------------------------------------------------------------
 
- -------------------------------------------------------------------------------
 
Aggregate Principal                                      Aggregate Principal
       Amount                                                  Amount
     of 4 3/4%                                          of 4 3/4% Debentures
     Debentures                                               Tendered
Held by You for the
      Account
 of the Undersigned
 
- -------------------------------------------------------------------------------
 
- -------------------------------------------------------------------------------
 
- -------------------------------------------------------------------------------
 
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  Unless otherwise indicated, the undersigned will be deemed to have tendered
the entire aggregate principal amount at maturity of Old Debentures held for
the account of the undersigned.
 
Signature(s): ____________________________
 
 _________________________________________
 
Please print name(s): ____________________
 
 _________________________________________
 
Date: , 1998
 
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