SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C.  20549

                                 SCHEDULE 13G


                                 (Rule 13d-102)


             INFORMATION STATEMENT PURSUANT TO RULES 13d-1 AND 13d-2


                   Under the Securities Exchange Act of 1934
                          (Amendment No. 1     )

                                  Sunoco, Inc.
             -----------------------------------------------------
                                (Name of Issuer)

                                  Common Stock
              -----------------------------------------------------
                         (Title of Class of Securities)

                                    86764P109
             -----------------------------------------------------
                                 (CUSIP Number)



Check the following box if a fee is  being paid with this statement [].


----------
*The  remainder of this cover page shall be filled out for a reporting  person's
initial filing on this form with respect to the subject class of securities, and
for any  subsequent  amendment  containing  information  which  would  alter the
disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the  Securities  Exchange  Act of
1934 ("Act") or otherwise  subject to the liabilities of that section of the Act
but  shall be  subject  to all other  provisions  of the Act  (however,  see the
Notes).



CUSIP No. 86764P109                   13G                    Page 2  of 8  Pages



--------------------------------------------------------------------------------
   1.  NAME OF REPORTING PERSON(S)
       S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON(S)

          Morgan  Stanley Dean  Witter &  Co.
          IRS  #  39-314-5972



--------------------------------------------------------------------------------
   2.  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
                                                             (a)  [  ]
                                                             (b)  [  ]


--------------------------------------------------------------------------------
   3.  SEC USE ONLY




--------------------------------------------------------------------------------
   4.  CITIZENSHIP OR PLACE OF ORGANIZATION

          The state of organization is Delaware.


--------------------------------------------------------------------------------
   NUMBER OF      5.   SOLE VOTING POWER
     SHARES            0
  BENEFICIALLY    --------------------------------------------------------------
    OWNED BY      6.   SHARED VOTING POWER
      EACH             4,423,539
   REPORTING      --------------------------------------------------------------
     PERSON       7.   SOLE DISPOSITIVE POWER
      WITH             0
                  --------------------------------------------------------------
                  8.   SHARED DISPOSITIVE POWER
                       4,452,471
--------------------------------------------------------------------------------
   9.  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

         4,452,471

--------------------------------------------------------------------------------
  10.  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*



--------------------------------------------------------------------------------
  11.  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

          5.24%

--------------------------------------------------------------------------------
  12.  TYPE OF REPORTING PERSON*

          IA, CO

--------------------------------------------------------------------------------
                     *SEE INSTRUCTIONS BEFORE FILLING OUT!


CUSIP No. 86764P109                   13G                    Page 3  of 8  Pages



--------------------------------------------------------------------------------
   1.  NAME OF REPORTING PERSON(S)
       S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON(S)

          Morgan Stanley Dean Witter Advisors Inc.
          IRS # 13-3680016

--------------------------------------------------------------------------------
   2.  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
                                                             (a)  [  ]
                                                             (b)  [  ]


--------------------------------------------------------------------------------
   3.  SEC USE ONLY




--------------------------------------------------------------------------------
   4.  CITIZENSHIP OR PLACE OF ORGANIZATION

          The state of organization is Delaware.


--------------------------------------------------------------------------------
   NUMBER OF      5.   SOLE VOTING POWER
     SHARES            0
  BENEFICIALLY    --------------------------------------------------------------
    OWNED BY      6.   SHARED VOTING POWER
      EACH             4,346,843
   REPORTING      --------------------------------------------------------------
     PERSON       7.   SOLE DISPOSITIVE POWER
      WITH             0
                  --------------------------------------------------------------
                  8.   SHARED DISPOSITIVE POWER
                       4,364,748
--------------------------------------------------------------------------------
   9.  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

          4,364,748

--------------------------------------------------------------------------------
  10.  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*



--------------------------------------------------------------------------------
  11.  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

          5.13%

--------------------------------------------------------------------------------
  12.  TYPE OF REPORTING PERSON*

          IA, CO

--------------------------------------------------------------------------------
                     *SEE INSTRUCTIONS BEFORE FILLING OUT!




CUSIP No. 86764P109                   13G                   Page 4  of  8  Pages





Item 1.     (a)   Name of Issuer:
                  Sunoco, Inc.
                  --------------------------------------------------------------
            (b)   Address of Issuer's Principal Executive Offices:
                  Ten Penn Center
                  1801 Market Street
                  Philadelphia, PA 19103-1699
                  --------------------------------------------------------------
Item 2.     (a)   Name of Person Filing:
                  (a)  Morgan Stanley Dean Witter & Co.
                  (b)  Morgan Stanley Dean Witter Advisors Inc.
                  --------------------------------------------------------------
            (b)   Address of Principal Business Office, or if None, Residence:
                  (a)  1585 Broadway
                       New  York, New  York  10036

                  (b)  Two World Trade Center
                       New  York, New  York  10048
                  --------------------------------------------------------------
            (c)   Citizenship:
                           Incorporated  by  reference  to  Item  4  of  the
                           cover page  pertaining  to  each  reporting  person.

                               -------------------------------------------------
            (d)   Title of Class of Securities:
                           Common Stock
                  --------------------------------------------------------------
            (e)   CUSIP Number:
                           86764P109
                               -------------------------------------------------

Item 3.           (a)  Morgan  Stanley  Dean  Witter &  Co. is (e) an Investment
                       Adviser  registered  under Section 203 of  the Investment
                       Advisers Act of 1940.

                  (b)  Morgan Stanley Dean Witter Advisors Inc. is (e) an
                       Investment Adviser registered under Section 203 of
                       the Investment Advisers Act of 1940.



CUSIP No. 86764P109                  13-G                   Page 5  of  8  Pages



Item 4.     Ownership.

               Incorporated  by  reference  to  Items  (5) - (9) and (11) of the
               cover page.

Item 5.     Ownership of Five Percent or Less of a Class.
               Inapplicable

Item 6.     Ownership of More Than Five Percent on Behalf of Another Person.

               Accounts managed on a discretionary  basis by Morgan Stanley Dean
               Witter Advisors Inc., a wholly owned subsidiary of Morgan Stanley
               Dean Witter & Co.,  are known to have the right to receive or the
               power to direct the receipt of  dividends  from,  or the proceeds
               from,  the sale of such  securities.  No such account  holds more
               than 5 percent of the class.

Item 7.     Identification and Classification of the Subsidiary which Acquired
            the Security Being Reported on By the Parent Holding Company.


Item 8.     Identification and Classification of Members of the Group.


Item 9.     Notice of Dissolution of Group.


Item 10.    Certification.

               By signing  below I certify that, to the best of my knowledge and
               belief,  the  securities  referred to above were  acquired in the
               ordinary course of business and were not acquired for the purpose
               of and do not have the  effect of  changing  or  influencing  the
               control of the issuer of such securities and were not acquired in
               connection  with or as a participant  in any  transaction  having
               such purpose or effect.


CUSIP No. 86764P109                   13-G                   Page 6  of  8 Pages


                                  Signature.


            After  reasonable  inquiry  and to the best of my  knowledge  and
            belief,  I  certify  that  the  information  set  forth  in  this
            statement is true, complete and correct.


Date:       February 14, 2001


Signature:  /s/ Dennine Bullard
            -----------------------------------------------------------------

Name/Title  Dennine Bullard / Morgan Stanley & Co. Incorporated
            -----------------------------------------------------------------
            MORGAN STANLEY DEAN WITTER & CO.

Date:       February 14, 2001


Signature:  /s/ James Wallin
            -----------------------------------------------------------------

Name/Title  James Wallin / First Vice President Morgan Stanley Dean Witter
                         Advisors Inc.
            -----------------------------------------------------------------
            MORGAN STANLEY DEAN WITTER ADVISORS INC.


                       INDEX TO EXHIBITS                             PAGE
                       -----------------                             ----

EXHIBIT 1       Agreement to Make a Joint Filing                       7

EXHIBIT 2       Secretary's Certificate Authorizing Dennine Bullard 8
                to Sign on behalf of Morgan Stanley Dean Witter & Co.


* Attention. Intentional misstatements or omissions of fact constitute federal
  criminal violations (see 18 U.S.C. 1001).

(022597DTI)