As filed with the Securities and Exchange Commission on January 7, 1998
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                    SECURITIES AND EXCHANGE COMMISSION
                          Washington, D.C.  20549

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                              SCHEDULE 14D-1
                             (Amendment No. 3)

            TENDER OFFER STATEMENT PURSUANT TO SECTION 14(d)(1)
                  OF THE SECURITIES EXCHANGE ACT OF 1934

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                            TRIMAS CORPORATION
                      (Exact name of Subject Company)

                              MASCOTECH, INC.
                        MASCOTECH ACQUISITION, INC.
                                 (Bidders)

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                       Common Stock, $.01 Par Value
                      (Title of Class of Securities)

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                                 896215100
                   (CUSIP Number of Class of Securities)

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                           David B. Liner, Esq.
                              MascoTech, Inc.
                            21001 Van Born Road
                          Taylor, Michigan 48180
                              (313) 274-7405

(Name, Address and Telephone Number of Persons Authorized to Receive Notices
        and Communications on Behalf of Person(s) Filing Statement)

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                              With Copies to:
                              
  David W. Ferguson, Esq.                   Jerome M. Schwartz, Esq.
   Davis Polk & Wardwell                     Dickinson Wright PLLC
   450 Lexington Avenue                 500 Woodward Avenue, Suite 4000
 New York, New York 10017                   Detroit, Michigan 48226
      (212) 450-4000                             (313) 223-3628
============================================================================== This Amendment No. 3 (this "Amendment") amends and supplements the Tender Offer Statement on Schedule 14D-1 (the "Schedule 14D-1") originally filed on December 17, 1997 by MascoTech, Inc., a Delaware corporation ("Parent"), and MascoTech Acquisition, Inc., a Delaware corporation and a wholly owned subsidiary of Parent ("Purchaser"), as amended by Amendment No. 1, dated December 22, 1997 and Amendment No. 2, dated December 31, 1997, relating to the offer by Purchaser to purchase all of the issued and outstanding shares (the "Shares") of common stock, $.01 par value per share, of TriMas Corporation, a Delaware corporation, at a price of $34.50 per Share, net to the seller in cash, upon the terms and subject to the conditions set forth in the Offer to Purchase dated December 17, 1997 and in the related Letter of Transmittal. All capitalized terms used in this Amendment without definition have the meanings attributed to them in the Schedule 14D-1. The item of the Schedule 14D-1 set forth below is hereby amended and supplemented as follows: Item 10. Additional Information On January 2, 1998, Parent received early termination of the applicable waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976 with respect to the Offer. SIGNATURE After due inquiry and to the best of my knowledge and belief, I certify that the information set forth in this Amendment is true, complete and correct. January 7, 1998 MASCOTECH, INC. By: /s/ David B. Liner ------------------------------------------- Name: David B. Liner Title: Vice President and Corporate Counsel MASCOTECH ACQUISITION, INC. By: /s/ David B. Liner ------------------------------------------- Name: David B. Liner Title: Secretary