1
 
                         NOTICE OF GUARANTEED DELIVERY
                                 FOR TENDER OF
                   9 7/8% SENIOR SUBORDINATED NOTES DUE 2008
                      (INCLUDING THOSE IN BOOK-ENTRY FORM)
                                       OF
 
                                  NEWCOR, INC.
 
     This form or one substantially equivalent hereto must be used to accept the
Exchange Offer of Newcor, Inc. (the "Issuer") made pursuant to the Prospectus
dated             , 1998 (the "Prospectus") if certificates for the outstanding
9 7/8% Senior Subordinated Notes due 2008 of the Issuer (the "Notes") are not
immediately available or if the procedure for book-entry transfer cannot be
completed on a timely basis or time will not permit all required documents to
reach the Exchange Agent prior to 5:00 p.m., New York City time, on the
Expiration Date of the Exchange Offer. Such form may be delivered or transmitted
by telegram, telex, facsimile transmission, mail or hand delivery to U.S. Bank
Trust National Association (the "Exchange Agent") as set forth below. In
addition, in order to utilize the guaranteed delivery procedure to tender Notes
pursuant to the Exchange Offer, a completed, signed and dated Letter of
Transmittal (or facsimile thereof) must also be received by the Exchange Agent
prior to 5:00 p.m., New York City time, on the Expiration Date. Capitalized
terms not defined herein are defined in the Prospectus.
 
              U.S. BANK TRUST NATIONAL ASSOCIATION, EXCHANGE AGENT
 

                                                          
 By Registered, Certified, or              By Hand:                 By First Class Mail:
  Overnight Mail or Courier:         U.S. Bank Trust N.A.           U.S. Bank Trust N.A.
     U.S. Bank Trust N.A.         4th Floor Bond Drop Window           P.O. Box 64485
  Attn: Specialized Finance         180 East Fifth Street          St. Paul, MN 55164-9549
           SPFT0414                   St. Paul, MN 55101
    180 East Fifth Street
      St. Paul, MN 55101

 
                                 By Facsimile:
                       (For Eligible Institutions Only):
                                 (612) 244-1537
 
     DELIVERY OF THIS INSTRUMENT TO AN ADDRESS OTHER THAN AS SET FORTH ABOVE, OR
TRANSMISSION OF INSTRUCTIONS VIA FACSIMILE OTHER THAN AS SET FORTH ABOVE, WILL
NOT CONSTITUTE A VALID DELIVERY.
 
Ladies and Gentlemen:
 
     Upon the terms and conditions set forth in the Prospectus and the
accompanying Letter of Transmittal, the undersigned hereby tenders to the Issuer
the principal amount of Notes set forth below pursuant to the guaranteed
delivery procedure described in "The Exchange Offer -- Guaranteed Delivery
Procedures" section of the Prospectus.
 
Principal Amount of Notes Tendered.*
 
$
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Certificate No(s). (if available):
 
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Total Principal Amount Represented by Certificate(s):
 
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*Must be in denominations of principal amount of $1,000 and any integral
multiple thereof.
   2
 
     All authority herein conferred or agreed to be conferred shall survive the
death or incapacity of the undersigned, and every obligation of the undersigned
hereunder shall be binding upon the heirs, personal representatives, successors
and assigns of the undersigned.

                                PLEASE SIGN HERE
 

                                                          
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                 Signature(s) of Owner(s)
                  or Authorized Signatory

Area Code and Telephone Number:
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        Must be signed by the holder(s) of Notes as their name(s) appear on
   certificates for Notes or on a security position listing, or by person(s)
   authorized to become registered holder(s) by endorsement and documents
   transmitted with this Notice of Guaranteed Delivery. If signature is by a
   trustee, executor, administrator, guardian, attorney-in-fact, officer or
   other person acting in a fiduciary or representative capacity, such person
   must set forth his or her full title below. If Notes will be delivered by
   book-entry transfer to The Depository Trust Company, provide account
   number.
 
                      PLEASE PRINT NAME(S) AND ADDRESS(ES)
 
   Name(s):
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   Capacity:
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   Address(es):
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   Account Number:
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   3
 
                                   GUARANTEE
 
                    (NOT TO BE USED FOR SIGNATURE GUARANTEE)
 
     The undersigned, a financial institution (including most banks, savings and
loan associations and brokerage houses) that is a participant in the Securities
Transfer Agents Medallion Program, the New York Stock Exchange Medallion
Signature Program or the Stock Exchanges Medallion Program, hereby guarantees
that the undersigned will deliver to the Exchange Agent the certificates
representing the Notes being tendered hereby or confirmation of book-entry
transfer of such Notes into the Exchange Agent's account at The Depository Trust
Company, in proper form for transfer, together with any other documents required
by the Letter of Transmittal, within three New York Stock Exchange trading days
after the Expiration Date.

Name of Firm
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Address
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Area Code & Telephone No.
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Authorized Signature
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Name
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     (PLEASE TYPE OR PRINT)
 
Title
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Date
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NOTE: DO NOT SEND CERTIFICATES REPRESENTING NOTES WITH THIS FORM. CERTIFICATES
      REPRESENTING NOTES SHOULD BE SENT ONLY WITH A COPY OF THE PREVIOUSLY
      EXECUTED LETTER OF TRANSMITTAL.