FIRST AMENDMENT TO CREDIT AGREEMENT

Exhibit 10.8

FIRST AMENDMENT TO

CREDIT AGREEMENT

THIS FIRST AMENDMENT TO CREDIT AGREEMENT (the “First Amendment”) dated as of March 28, 2005, is an amendment to that certain CREDIT AGREEMENT dated February 20, 2004 (the “Original Agreement”), and is by and among NEWCOR, INC., a Delaware corporation (“Borrower”), the other parties identified on the signature pages hereto as Guarantors and such other parties as may from time to time become a party hereto (“Guarantors”), and NATIONAL CITY BANK OF THE MIDWEST (formerly known as NATIONAL CITY BANK OF MICHIGAN/ILLINOIS), a national banking association, Individually and as agent for NATIONAL CITY BANK a national banking association (“Lender”).

RECITALS:

A. Capitalized terms used but not otherwise defined in this First Amendment shall have the meanings ascribed thereto in the Original Agreement. Reference in any Loan Document to the Original Agreement shall be deemed to refer to the Original Agreement as amended by this First Amendment.

B. The Borrower and the Bank desire to amend the Original Agreement to reduce the amount of the Revolving Credit Loan.

NOW THEREFORE, in consideration of the mutual covenants contained herein and for good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties agree as follows:

Amendments to the Original Agreement,

2. Representations. Borrower and Guarantors represent and warrant to Bank (and Bank relies upon such representations and warranties in entering into this First Amendment) as follows:

3. Guarantor Acknowledgement and Consent. The Guarantors hereby acknowledge and consent to this First Amendment and agree that they remain obligated to Bank on the Obligations pursuant to the Guarantees and each Guarantor shall execute this First Amendment constituting the acknowledgment and agreement of each Guarantor to the amendments contained herein.

4. Miscellaneous.

(a) Binding Effect. This Amendment shall be binding upon and shall inure to the benefit of the parties hereto and their respective successors and assigns, provided that no party other than Bank may assign any of its rights or obligations hereunder without the prior written consent of Bank.

(b) Governing Law. THIS AMENDMENT SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE INTERNAL LAWS OF THE STATE OF MICHIGAN APPLICABLE TO CONTRACTS MADE AND PERFORMED IN SUCH STATE.

(c) Counterparts; Facsimile Signatures. This Amendment may be executed in multiple counterparts, each of which shall be deemed to be an original and all of which when taken together shall constitute one and the same instrument. A facsimile signature shall be effective as an original signature.

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IN WITNESS WHEREOF, the parties hereto have executed this First Amendment as of the date first above written.

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