TENTH AMENDMENT TO LOAN AND SECURITY AGREEMENT, LIMITED WAIVER AND AMENDMENT

Exhibit 10.40

TENTH AMENDMENT TO

LOAN AND SECURITY AGREEMENT,

LIMITED WAIVER AND AMENDMENT

This TENTH AMENDMENT TO LOAN AND SECURITY AGREEMENT, LIMITED WAIVER, AND AMENDMENT (this “ Amendment ”), dated October 31, 2007, by and among LASALLE BUSINESS CREDIT, LLC, a Delaware limited liability company (“ LaSalle ”), with its principal office at 450 North Brand Blvd., Suite 950, Glendale, California 91203, the financial institutions that, from time to time, become a party to the Loan Agreement (hereinafter defined) (such financial institutions, collectively, the “ Lenders ” and each individually, a “ Lender ”), LaSalle as agent for the Lenders (in such capacity, the “ Agent ”), and IMPCO TECHNOLOGIES, INC., a Delaware corporation, with its principal office at 3030 South Susan Street, Santa Ana, California 92704 (the “ Borrower ”).

A. WHEREAS, LaSalle, as a Lender and the Agent, and the Borrower are parties to a Loan and Security Agreement dated as of July 18, 2003 (as amended, restated, supplemented, or otherwise modified from time to time, the “ Loan Agreement ”), pursuant to which the Lenders have agreed, upon satisfaction of certain conditions, to make Revolving Advances and other financial accommodations to the Borrower; and

B. WHEREAS, the Borrower has informed the Lenders and the Agent that it is not in compliance with the following financial covenants for the periods indicated (hereinafter collectively “ October Existing Defaults ”) which October Existing Defaults each constitute an Event of Default under Paragraph 16(b) of the Loan Agreement:

(i) U.S. Minimum Pre-Tax Income covenant set forth in Paragraph 14(x)(v) of the Loan Agreement for the months ended December 31, 2006, August 31, 2007 and September 30, 2007;

(ii) Minimum Tangible Net Worth covenant set forth in Paragraph 14(x)(i) of the Loan Agreement for the fiscal quarter ending September 30, 2007;

(iii) Minimum Consolidated EBITDA covenant set forth in Paragraph 14(p)(ii), Minimum U.S. EBITDA covenant as previously set forth in Paragraph 14(x)(ii) , Fixed Charge Coverage Ratio covenant as previously set forth in Paragraph 14(x)(iii) , U.S. Leverage Ratio covenant as previously set forth in Paragraph 14(x)(iv); Fixed Charge Coverage Ratio covenant as previously set forth in Paragraph 14(p)(iii) and the Consolidated Leverage Ratio covenant as previously set forth in Paragraph 14(p)(iv) of the Loan Agreement, each for each of the fiscal quarters ending June 30, 2004, through and including September 30, 2006.

C. WHEREAS, the Borrower has requested that the Lenders and the Agent agree to: (a) waive the October Existing Defaults and (b) amend the Loan Agreement in certain respects, and the Lenders and the Agent are willing to waive the October Existing Defaults and amend Loan Agreement, all on the terms and subject to the conditions hereinafter set forth. Capitalized terms used herein, unless otherwise defined herein, shall have the meaning set forth in the Loan Agreement.

NOW THEREFORE, the parties hereto agree as follows:

1. Recitals . The Borrower confirms that the Recitals above are true and correct.

2. Limited Waiver .

(a) The Lenders and the Agent hereby waive the October Existing Defaults and agree not to exercise any rights or remedies available as a result of the occurrence thereof.

(b) The waiver granted herein is a one-time waiver, given solely for the specific covenants and specific time periods set forth in Recital B hereof. Nothing contained in this Amendment constitutes a waiver by the Lenders or the Agent of any other terms or provisions of the Loan Agreement or the Other Agreements, whether or not the Lenders or the Agent have any knowledge thereof, nor may anything contained in this Amendment be deemed a waiver by the Lenders or the Agent of any non-compliance with the terms or provisions of the Loan Agreement or the Other Agreements that may occur after the date of this Amendment.

3. Reset of Certain Covenants .

(a) Paragraph 14(x)(v) of the Loan Agreement is hereby amended and restated to read in its entirety as follows:

“(v) U.S. Minimum Pre-Tax Income . Borrower shall maintain and cause the U.S. Consolidated Group to maintain, as of the end of each fiscal period set forth below, Pre-Tax Income of not less than the respective amount set forth below opposite each such fiscal period:

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(b) Paragraph 14(x)(i) of the Loan Agreement is hereby amended and restated in its entirety to read as follows:

“ (i) Tangible Net Worth . Borrower shall cause the U.S. Consolidated Group to maintain, as of the end of each fiscal quarter, Tangible Net Worth of not less than the respective amount set forth below opposite each such fiscal quarter:

4. Extension of Term . The first sentence of Paragraph 12(a) of the Loan Agreement is hereby deleted and replaced in its entirety by the following:

“(a) This Agreement shall be in effect from the date hereof until January 31, 2008 (the “ Term ”), unless the due date of the Liabilities is accelerated pursuant to paragraph 17 hereof, in which case this Agreement shall terminate on the date thereafter

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that the Liabilities are paid in full, provided , however , that the security interests and liens created under this Agreement and the Other Agreements shall survive such termination until the date upon which payment and satisfaction in full of the Liabilities shall have occurred.”

5. Subordinated Debt Payments . The Borrower has represented to the Agent and the Lenders that it will not make any payments of principal to MTM until after January 31, 2008, payment in full of the Liabilities and termination of the Loan Agreement. Alternatively, Borrower may make payments of principal to MTM so long as MTM immediately returns the same amount of funds to Borrower as a subordinated loan which will not be repaid in whole or in part until after payment in full of the Liabilities and termination of the Loan Agreement. The foregoing shall be deemed an additional representation and warranty under Paragraph 13 of the Loan Agreement.

6. Revolving Loan Commitment . The definition of “Revolving Loan Commitment” set forth in Paragraph 1(a) of the Loan Agreement is hereby amended and restated to read in its entirety as follows:

“ ‘ Revolving Loan Commitment ’ shall mean the sum of $7,000,000.”

7. Ex