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EXHIBIT 4(l)

                                 AMENDMENT NO. 7

                     SEVENTH AMENDMENT TO THIRD AMENDED AND
                       RESTATED REVOLVING CREDIT AGREEMENT

         THIS SEVENTH AMENDMENT, dated as of the 31st day of December, 1999, by
and between Newcor, Inc., a Delaware corporation, of Bloomfield Hills, Michigan
(herein called "Company") and Comerica Bank, a Michigan banking corporation, of
Detroit, Michigan (herein called "Bank");

                                   WITNESSETH:

         WHEREAS, Company and Bank desire to amend that certain Third Amended
and Restated Revolving Credit Agreement dated as of January 15, 1998, entered
into by and between Company and Bank, which was amended by six amendments
(herein called "Agreement");

         NOW, THEREFORE, it is agreed that the Agreement is amended as follows:

         1.       The  definition  of "Base Net  Worth" in  Section 1 of the
Agreement  is  amended to read in its entirety:

                  "`Base Net Worth' shall mean, $19,000,000 less an amount equal
         to the lesser of the `impairment charge' taken by Company with respect
         to fiscal year 1999 (`Impairment Charge') and $9,000,000. On the last
         day of each fiscal quarter of Company commencing March 31, 2000, Base
         Net Worth shall be increased by an amount equal to 50% of Net Income
         for the fiscal quarter then ended. Such increase shall be effective on
         the last day of the fiscal quarter in which such determination is made.
         Any fiscal quarter with respect to which Net Income is less than zero,
         Net Income shall be deemed to be zero."

         2.       The  definition  of  "EBITDA"  set forth in  Section 1 of the
Agreement  is  amended  to read as follows:

                  "`EBITDA' shall mean as of any date of determination, Net
         Income for the four preceding fiscal quarters ending on such date of
         determination plus, to the extent deducted in determining Net Income,
         (1) depreciation and amortization expense of Company and its
         consolidated Subsidiaries for such period, (2) interest expense of
         Company and its consolidated Subsidiaries for such period, (3) income
         taxes of Company and its consolidated Subsidiaries for such period, and
         (4) an amount equal to the lesser of the Impairment Charge and
         $9,000,000, all as determined in accordance with generally accepted
         accounting principles consistently applied."

         3. Company hereby represents and warrants that, after giving effect to
the amendment contained herein, (a) execution, delivery and performance of this
Amendment and any other documents and instruments required under this Amendment
or the Agreement are within Company's corporate powers, have been duly
authorized, are not in contravention of law or the terms of Company's
Certificate of Incorporation or Bylaws, and do not require the consent or
approval of any governmental body, agency, or authority; and this Amendment and
any other documents and instruments required under this Amendment or the
Agreement, will be valid and binding in accordance with their terms; (b) the
continuing representations and warranties of Company set forth in Sections 5.1
through 5.7 and 5.9 through 5.15 of the Agreement are true and correct on and as
of the date hereof with the same force and effect as made on and as of the date
hereof; (c) the continuing representations and warranties of Company set forth
in Section 5.8 of the Agreement are true and correct as of the date hereof with
respect to the most recent financial statements furnished to the Bank by Company
in accordance with Section 6.1 of the Agreement; and (d) no event of default, or
condition or event which, with the giving of notice or the running of time, or
both, would constitute an event of default under the Agreement, has occurred and
is continuing as of the date hereof.


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         4. This Amendment shall be effective upon (a) execution of this
Amendment by Company and Bank (b) execution by the Guarantors of the attached
Acknowledgment, and (c) payment by Company to Bank of a non-refundable $15,000
closing fee.

         5. Except as modified hereby, all of the terms and conditions of the
Agreement shall remain in full force and effect.

         WITNESS the due execution hereof on the day and year first above
written.

COMERICA BANK                                        NEWCOR, INC.


By:  /s/ Brian E. Marshall                           By:  /s/ James J. Connor
   -------------------------------                      ------------------------

Its: Vice President                                  Its: Vice President
                                                         -----------------------

                                                     By:  /s/ Keith F. Hale
                                                        ------------------------

                                                     Its: President and CEO
                                                         -----------------------


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                                 ACKNOWLEDGMENT



         The undersigned accept and agree to the Amendment No. 7 to the Third
Amended and Restated Revolving Credit Agreement and agree to the continued
effectiveness of the Guaranties originally executed and delivered to Comerica
Bank by the undersigned on January 15, 1998 and on March 4, 1998, as applicable.


                                                    ROCHESTER GEAR, INC.



                                                    By:   /s/ James J. Connor
                                                       -------------------------

                                                    Its:  Vice President
                                                        ------------------------


                                                    By:   /s/ Keith F. Hale
                                                       -------------------------

                                                    Its:  President and CEO
                                                        ------------------------


                                                    ENC CORP.



                                                    By:   /s/ James J. Connor
                                                       -------------------------

                                                    Its:  Vice President
                                                        ------------------------


                                                    By:   /s/ Keith F. Hale
                                                       -------------------------

                                                    Its:   President and CEO
                                                        ------------------------





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DECO TECHNOLOGIES, INC.                     PLASTRONICS PLUS, INC.

By:  /s/ James J. Connor                    By:  /s/ James J. Connor
   ----------------------------                ---------------------------------

Its: Vice President                         Its: Vice President
    ---------------------------                 --------------------------------

By:  /s/ Keith F. Hale                      By:  /s/ Keith F. Hale
   ----------------------------                ---------------------------------

Its: President and CEO                      Its: President and CEO
    ---------------------------                 --------------------------------

DECO INTERNATIONAL, INC.                    NEWCOR M-T-L, INC.

By:  /s/ James J. Connor                    By:  /s/ James J. Connor
   ----------------------------                 --------------------------------

Its: Vice President                         Its: Vice President
    ---------------------------                 --------------------------------

By:  /s/ Keith F. Hale                      By:  /s/ Keith F. Hale
   ----------------------------                ---------------------------------

Its: President and CEO                      Its: President and CEO
    ---------------------------                 --------------------------------

TURN-MATIC, INC.                            GRAND MACHINING COMPANY

By:  /s/ James J. Connor                    By:  /s/ James J. Connor
   ----------------------------                ---------------------------------

Its: Vice President                         Its: Vice President
    ---------------------------                 --------------------------------

By:  /s/ Keith F. Hale                      By:  /s/ Keith F. Hale
   ----------------------------                ---------------------------------

Its: President and CEO                      Its: President and CEO
    ---------------------------                 --------------------------------

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