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                                                                    Exhibit 4.5

                           SECOND AMENDMENT AGREEMENT


     This Second Amendment Agreement is made as of the 1st day of November,
1999, among PARK-OHIO INDUSTRIES, INC., an Ohio corporation ("Borrower"), the
banking institutions listed on SCHEDULE 1 to the Credit Agreement, as
hereinafter defined ("Banks"), KEYBANK NATIONAL ASSOCIATION, as administrative
agent for the Banks ("Administrative Agent"), and THE HUNTINGTON NATIONAL BANK,
as co-agent for the Banks ("Co-Agent" and, together with Administrative Agent,
"Agents").

     WHEREAS, Borrower, Agents and the Banks are parties to a certain Amended
and Restated Credit Agreement dated as of November 2, 1998, as amended and as it
may from time to time be further amended, restated or otherwise modified, which
provides, among other things, for loans aggregating One Hundred Fifty Million
Dollars ($150,000,000), all upon certain terms and conditions (the "Credit
Agreement");

     WHEREAS, Borrower, Agents and the Banks desire to amend the Credit
Agreement to provide for an additional revolving credit tranche thereunder and
to modify certain other provisions thereof; and

     WHEREAS, each term used herein shall be defined in accordance with the
Credit Agreement:

     NOW, THEREFORE, in consideration of the premises and mutual covenants
contained herein and for other valuable considerations, Borrower, Agents and the
Banks agree as follows:

     1.  Article I of the Credit Agreement is hereby amended to delete the
definitions of "Advantage", "Applicable Margin", "Commitment", "Commitment
Percentage", "Commitment Period", "Indenture", "Loan", "Note", "Senior
Subordinated Note", "Senior Subordinated Noteholders", "Total Commitment Amount"
and "Total Senior Funded Indebtedness" therefrom and to insert in place thereof
the following:

         "Advantage" shall mean any payment (whether made voluntarily or
     involuntarily, by offset of any deposit or other indebtedness or otherwise)
     received by any Bank in respect of the Debt, if such payment results in
     that Bank having less than its Pro Rata Share of the Applicable Debt then
     outstanding, than was the case immediately before such payment.

         "Applicable Margin" shall mean, with respect to any Loan, the number
     of basis points (depending upon whether such Loan is a Prime Rate Loan or a
     LIBOR Loan) set forth in the following matrix:

-------------------------------------------------------------------------------
                                         APPLICABLE BASIS      APPLICABLE BASIS
 TYPE OF LOAN                            POINTS FOR LIBOR      POINTS FOR PRIME
                                              LOANS               RATE LOANS
--------------------------------------------------------------------------------
Tranche A Loan                            90 basis points      -100 basis points
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--------------------------------------------------------------------------------
Tranche B Loan                           150 basis points       -50 basis points
--------------------------------------------------------------------------------
Tranche C Loan (at any time that there   170 basis points       -30 basis points
is no Tranche D Loan outstanding)
--------------------------------------------------------------------------------
Tranche C Loan (at any time that there   185 basis points       -15 basis points
is a Tranche D Loan outstanding)
--------------------------------------------------------------------------------
Tranche D Loan                           220 basis points        20 basis points
--------------------------------------------------------------------------------


     Each change in the Applicable Margin with respect to any Tranche C Loan
     shall be effective immediately. The above matrix does not modify or waive,
     in any respect, the requirements of Section 5.7 hereof, the rights of the
     Banks to charge the Default Rate, or the rights and remedies of Agents and
     the Banks pursuant to Articles VII and VIII hereof.

         "Commitment" shall mean the obligation hereunder of the Banks, during
     the applicable Commitment Period, to make Loans pursuant to the Tranche A
     Commitments, the Tranche B Commitments, the Tranche C Commitments and the
     Tranche D Commitments, up to the Total Commitment Amount.

         "Commitment Percentage" shall mean Applicable Commitment Percentage.

         "Commitment Period" shall mean (a) with respect to the Tranche A
     Commitments, the Tranche B Commitments and the Tranche C Commitments, the
     period from the Closing Date to April 30, 2001, and (b) with respect to the
     Tranche D Commitments, the period from the Tranche D Closing Date to
     April 30, 2001; or such earlier date on which the Commitment shall have
     been terminated pursuant to Article VIII hereof.

         "Indenture" shall mean both of the following and any thereof (a) the
     1997 Indenture and (b) the 1999 Indenture; as either of the foregoing may,
     with the prior written consent of Administrative Agent and the Majority
     Banks, be from time to time amended, restated or otherwise modified or
     replaced.

         "Loan" shall mean the credit extended to Borrower by the Banks in
     accordance with Section 2.1A, B, C or D hereof.

         "Note" shall mean any Tranche A Note, Tranche B Note, Tranche C Note,
     Tranche D Note or other note delivered pursuant to this Agreement.

         "Senior Subordinated Noteholder" shall mean any one of the Senior
     Subordinated Noteholders under any Indenture.

         "Senior Subordinated Notes" shall mean the Senior Subordinated Notes
     issued pursuant to any Indenture.



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         "Total Commitment Amount" shall mean the principal amount of One
     Hundred Seventy-Five Million Dollars ($175,000,000) (or such lesser amount
     as shall be determined pursuant to Section 2.5 hereof).

         "Total Senior Funded Indebtedness" shall mean, on a Consolidated basis
     and in accordance with GAAP, (a) Total Funded Indebtedness minus (b) all
     Subordinated Indebtedness.

     2.  Article I of the Credit Agreement is hereby amended to add the
following new definitions thereto:

         "Applicable Commitment Percentage" shall mean, for each Bank, (a) with
     respect to the Tranche A Commitments, the Tranche B Commitments and the
     Tranche C Commitments, the percentage set forth opposite such Bank's name
     under the column headed "Tranche A through Tranche C Commitment Percentage"
     as described in SCHEDULE 1 hereof; and (b) with respect to the Tranche D
     Commitments, the percentage set forth opposite such Bank's name under the
     column headed "Tranche D Commitment Percentage" as described in SCHEDULE 1
     hereof.

         "Applicable Debt" shall mean (a) with respect to the Tranche A
     Commitments, the Tranche B Commitments and the Tranche C Commitments,
     collectively, (i) all Indebtedness incurred by Borrower to Agents or the
     Banks pursuant to this Agreement (other than pursuant to the Tranche D
     Commitments) and includes the principal of and interest on all Notes (other
     than the Tranche D Notes), (ii) each extension, renewal or refinancing
     thereof in whole or in part, and (iii) the commitment fees, other fees and
     any prepayment fees payable hereunder (other than the commitment fees and
     any prepayment fees payable in connection with the Tranche D Commitments);
     and (b) with respect to the Tranche D Commitments, collectively, (i) all
     Indebtedness incurred by Borrower to Agents or the Banks pursuant to the
     Tranche D Commitments and includes the principal of and interest on the
     Tranche D Notes, (ii) each extension, renewal or refinancing thereof in
     whole or in part, and (iii) the commitment fees and any prepayment fees
     payable in connection with the Tranche D Commitments.

         "Fixed Charge Coverage Ratio Condition" shall mean any time that (a)
     Borrower's Consolidated Fixed Charge Coverage Ratio (as defined in the
     Indenture) is less than 2.25 to 1.00, as calculated in accordance with the
     terms and conditions of the Indenture, or (b) any Subsidiary's Consolidated
     Fixed Charge Coverage Ratio (as defined in the Indenture) is less than 2.50
     to 1.00, as calculated in accordance with the terms and conditions of the
     Indenture.

         "1997 Indenture" shall mean that certain Indenture dated as of
     November 25, 1997, between Borrower and Norwest Bank Minnesota, National
     Association, as trustee, pursuant to which the Senior Subordinated Notes
     were issued to the Senior Subordinated Noteholders,



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         as the same may, with the prior written consent of Administrative Agent
         and the Majority Banks, be from time to time amended, restated or
         otherwise modified or replaced.

         "1999 Indenture" shall mean that certain Indenture dated as of June 2,
     1999, between Borrower and Norwest Bank Minnesota, National Association, as
     trustee, pursuant to which the Senior Subordinated Notes were issued to the
     Senior Subordinated Noteholders, as the same may, with the prior written
     consent of Administrative Agent and the Majority Banks, be from time to
     time amended, restated or otherwise modified or replaced.

         "Pro Rata Basis" or "pro rata basis" shall mean distribution to the
     Banks by Administrative Agent in accordance with the Applicable Commitment
     Percentages.

         "Pro Rata Share" or "pro rata share" shall mean, with respect to the
     Applicable Debt, a Bank's share in accordance with such Bank's Applicable
     Commitment Percentage.

         "Ratable Account" or "ratable account" shall mean each Bank's share of
     the Applicable Debt in accordance with such Bank's Applicable Commitment
     Percentage.

         "Ratable Share" or "ratable share" shall mean each Bank's share of the
     Applicable Debt in accordance with such Bank's Applicable Commitment
     Percentage.

         "Ratably" or "ratably" shall mean in accordance with each Bank's
     Ratable Share.

         "Tranche D Bank" shall mean any Bank with a Tranche D Commitment.

         "Tranche D Closing Date" shall mean November 1, 1999.

         "Tranche D Commitments" shall mean the obligation hereunder of each
     Tranche D Bank to make Tranche D Loans, during the applicable Commitment
     Period, up to the amount set forth opposite such Tranche D Bank's name
     under the column headed "Tranche D Commitment Amount" as set forth on
     SCHEDULE 1 hereof (or such lesser amount as shall be determined pursuant to
     Section 2.5 hereof); provided that the aggregate amount of the Tranche D
     Commitments shall not exceed Twenty-Five Million Dollars ($25,000,000).

         "Tranche D Conditions" shall include the following: (a) any payment of
     principal under this Agreement shall be applied first to the principal then
     outstanding on the Tranche D Commitments; (b) any payment of interest under
     this Agreement shall be applied first to the interest then outstanding on
     the Tranche D Commitments; and (c) any payment of commitment fees or other
     fees owing under this Agreement shall be applied first to the commitment
     and other fees then owing with respect to the Tranche D Commitments.

         "Tranche D Leverage Ratio Condition" shall mean any time that a
     Tranche D Loan is outstanding.



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         "Tranche D Loan" shall mean a Loan granted to Borrower by the Tranche D
     Banks in accordance with Section 2.1D hereof.

         "Tranche D Note" shall mean the Tranche D Note executed and delivered
     pursuant to Section 2.1D hereof.

     3.  Section 2.1 of the Credit Agreement is hereby amended to delete the
second and third paragraphs therefrom and to insert in place thereof the
following:

         Each Bank, for itself and not one for any other, agrees to participate
     in Loans made hereunder during the Commitment Period on such basis that
     (a) immediately after the completion of any borrowing by Borrower, the
     aggregate principal amount then outstanding on the Notes issued to such
     Bank shall not be in excess of the Maximum Amount for such Bank, and
     (b) such aggregate principal amounts outstanding on the Tranche A Note, the
     Tranche B Note and the Tranche C Note, respectively, issued to such Bank
     shall represent that percentage of the aggregate principal amount then
     outstanding on all Tranche A Notes, Tranche B Notes and Tranche C Notes
     (including all such Notes held by such Bank), respectively, which is such
     Bank's Applicable Commitment Percentage; and (c) such aggregate principal
     amount outstanding on the Tranche D Note issued to such Bank shall
     represent that percentage of the aggregate principal amount then
     outstanding on all Tranche D Notes (including the Tranche D Note held by
     such Bank) which is such Bank's Applicable Commitment Percentage.

         Each borrowing from the Banks hereunder shall be made pro rata
     according to the Banks' respective Applicable Commitment Percentages. The
     Loans may be made as Tranche A Loans, Tranche B Loans, Tranche C Loans and
     Tranche D Loans as follows:

     4.  Section 2.1 of the Credit Agreement is hereby amended to add the
following new subsection D thereto:

         D. Tranche D Loans. Subject to the terms and conditions of this
     Agreement, during the applicable Commitment Period, the Tranche D Banks
     shall make a Tranche D Loan or Tranche D Loans to Borrower in such amount
     or amounts as Borrower may from time to time request, but not exceeding in
     aggregate principal amount at any time outstanding hereunder the aggregate
     amount of the Tranche D Commitments; provided, however, that Borrower shall
     not request any Tranche D Loan hereunder unless the Tranche A Commitments,
     Tranche B Commitments and Tranche C Commitments have been fully funded.
     Borrower shall have the option, subject to the terms and conditions set
     forth herein, to borrow Tranche D Loans, maturing on the last day of the
     Commitment Period, by means of any combination of (a) Prime Rate Loans, or
     (b) LIBOR Loans.

         Borrower shall pay interest, for the benefit of the Tranche D Banks, on
     the unpaid principal amount of Prime Rate Loans outstanding from time to
     time from the date thereof



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     until paid at the Derived Prime Rate from time to time in effect. Interest
     on such Prime Rate Loans shall be payable, commencing December 31, 1999,
     and on the last day of each succeeding March, June, September and December
     of each year and at the maturity thereof.

         Borrower shall pay interest, for the benefit of the Tranche D Banks, on
     the unpaid principal amount of each LIBOR Loan outstanding from time to
     time, from the date thereof until paid, at the Derived LIBOR Rate, fixed in
     advance for each Interest Period as herein provided for each such Interest
     Period. Interest on such LIBOR Loans shall be payable on each Interest
     Adjustment Date with respect to an Interest Period (provided that if an
     Interest Period exceeds three (3) months, the interest must be paid every
     three (3) months, commencing three (3) months from the beginning of such
     Interest Period).

         The obligation of Borrower to repay the Prime Rate Loans and the LIBOR
     Loans made by each Tranche D Bank and to pay interest thereon shall be
     evidenced by a Tranche D Note of Borrower in the form of EXHIBIT F hereto,
     dated as of the Tranche D Closing Date, and payable to the order of such
     Tranche D Bank in the principal amount of its Tranche D Commitment, or, if
     less, the aggregate unpaid principal amount of Tranche D Loans made
     hereunder by such Bank. Subject to the provisions of this Agreement,
     Borrower shall be entitled under this Section 2.1D to borrow funds, repay
     the same in whole or in part and re- borrow hereunder at any time and from
     time to time during the applicable Commitment Period.

     5.  The Credit Agreement is hereby amended to delete Section 2.3 therefrom
and to insert in place thereof the following:

         SECTION 2.3. PAYMENT ON NOTES, ETC. Each payment made on Loans
     hereunder shall be applied first to Tranche D Loans, if any are
     outstanding, then to Tranche C Loans, if any are outstanding, then to
     Tranche B Loans, if any are outstanding, and then to Tranche A Loans. All
     payments of principal, interest and commitment and other fees shall be made
     to Administrative Agent in immediately available funds for the account of
     the Banks on a Pro Rata Basis (except as to payments made exclusively for
     the benefit of Administrative Agent pursuant to the Agent Fee Letter), and
     Administrative Agent, within one (1) Business Day, shall distribute to each
     Bank, in accordance with the Tranche D Conditions, its Ratable Share of the
     amount of principal, interest, and commitment and other fees received by it
     for the account of such Bank. Whenever payments are made to Administrative
     Agent "for the benefit of the Banks", "for the benefit of the Banks" shall
     mean on a Pro Rata Basis. Each Bank shall record (a) any principal,
     interest or other payment, and (b) the principal amount of the Prime Rate
     Loans and the LIBOR Loans and all prepayments thereof and the applicable
     dates with respect thereto, by such method as such Bank may generally
     employ; provided, however, that failure to make any such entry shall in no
     way detract from Borrower's obligations under each such Note. The aggregate
     unpaid amount of Loans set forth on the records of Administrative Agent
     shall be rebuttably presumptive evidence of the principal and interest
     owing and unpaid on each Note.



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     Whenever any payment to be made hereunder, including, without limitation,
     any payment to be made on any Note, shall be stated to be due on a day that
     is not a Business Day, such payment shall be made on the next succeeding
     Business Day and such extension of time shall in each case be included in
     the computation of the interest payable on such Note; provided, however,
     that with respect to any LIBOR Loan, if the next succeeding Business Day
     falls in the succeeding calendar month, such payment shall be made on the
     preceding Business Day and the relevant Interest Period shall be adjusted
     accordingly.

     6.  Section 2.4 of the Credit Agreement is hereby amended to delete the
first paragraph therefrom and to insert in place thereof the following:

         SECTION 2.4. PREPAYMENT. Borrower shall have the right at any time or
     from time to time to prepay, on a Pro Rata Basis for all of the Banks, all
     or any part of the principal amount of the Notes then outstanding as
     designated by Borrower, plus interest accrued on the amount so prepaid to
     the date of such prepayment, subject, however, to the Tranche D Conditions.
     Borrower shall give Administrative Agent notice of prepayment of any Prime
     Rate Loan by not later than 11:00 A.M. (Cleveland, Ohio time) on the
     Business Day such prepayment is to be made and written notice of the
     prepayment of any LIBOR Loan not later than 1:00 P.M. (Cleveland, Ohio
     time) three (3) Business Days before the Business Day on which such
     prepayment is to be made. Prepayments of Prime Rate Loans shall be without
     any premium or penalty.

     7.  Section 2.5 of the Credit Agreement is hereby amended to delete
subsection (e) therefrom and to insert in place thereof the following:

         (e) Borrower may at any time or from time to time permanently reduce in
     whole or in part the Commitment of the Banks hereunder to an amount not
     less than the aggregate principal amount of the Loans then outstanding, by
     giving Agents not fewer than five (5) Business Days' notice, provided that
     (i) any partial reduction shall be applied, on a Pro Rata Basis for all of
     the Banks, first to the Tranche D Commitments, then to the Tranche C
     Commitments, then to the Tranche B Commitments and, finally, to the Tranche
     A Commitments, and (ii) any partial reduction shall be in an aggregate
     amount of Five Million Dollars ($5,000,000) or any multiple thereof.
     Administrative Agent shall promptly notify each Bank of the date of each
     such reduction and such Bank's proportionate share thereof. After each such
     reduction, the commitment fees payable hereunder shall be calculated upon
     the Commitment of the Banks as so reduced. If Borrower reduces in whole the
     Commitment of the Banks, on the effective date of such reduction (Borrower
     having prepaid in full the unpaid principal balance, if any, of the Notes,
     together with all interest and commitment and other fees accrued and
     unpaid), all of the Notes shall be delivered to Administrative Agent marked
     "Canceled" and Administrative Agent shall redeliver such Notes to Borrower.
     Any partial reduction in the Commitment of the Banks shall be effective
     during the remainder of the Commitment Period.



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     8.  Section 2.5 of the Credit Agreement is hereby amended to add new a
subsection (f) thereto as follows:

         (f) Borrower shall pay to Administrative Agent, for the account of the
     Tranche D Banks, as a consideration for the Tranche D Commitments, a
     commitment fee from the Tranche D Closing Date to and including the last
     day of the Commitment Period equal to (i) one-half percent (1/2%) per
     annum, times (ii) the average daily unborrowed amount of the Tranche D
     Commitments. The commitment fee shall be payable, in arrears, on
     December 31, 1999 and on the last day of each March, June, September and
     December thereafter, and on the last day of the Commitment Period.

     9.  The Credit Agreement is hereby amended to add a new Section 2.9 thereto
as follows:

         SECTION 2.9. FIXED CHARGE COVERAGE RATIO CONDITION. Borrower shall
     provide immediate written notice to Agents and the Banks at any time that
     the Fixed Charge Coverage Ratio Condition exists or, within the next three
     (3) months, is likely to exist, and, so long as the Fixed Charge Coverage
     Ratio exists, Borrower shall not request any Loan, and the Banks shall not
     be obligated to make any Loan, unless (a) the proceeds of such Loan shall
     constitute Permitted Indebtedness (as defined in the Indenture), and
     (b) upon request of Administrative Agent, Borrower shall provide to the
     Banks such evidence of use of proceeds of the Loans and such opinion of
     counsel with respect to the Indenture, as Administrative Agent may require
     in its reasonable discretion.

     10. Section 5.7 of the Credit Agreement is hereby amended to delete
subsection (c) therefrom and to insert in place thereof the following:

         (c) LEVERAGE RATIO. Borrower shall not suffer or permit at any time the
     Leverage Ratio to exceed (i) 5.00 to 1.00 for the period from the Closing
     Date through December 30, 1999 at any time that the Leverage Ratio
     Condition exists during such period, (ii) on December 31, 1999 through
     June 29, 2000, 5.00 to 1.00 or, in the event that the Tranche D Leverage
     Ratio Condition exists, 4.50 to 1.00, and (iii) on June 30, 2000 and
     thereafter, 5.00 to 1.00 or, in the event that the Tranche D Leverage Ratio
     Conditions exists, 4.00 to 1.00.

     11. The Credit Agreement is hereby amended to delete Section 6.18 therefrom
and to insert in place thereof the following:

         SECTION 6.18. INDENTURE. (a) No Event of Default (as defined in the
     Indenture) or Default (as defined in the Indenture) exists, nor will any
     such Event of Default or Default exist immediately after the granting of
     any Loan, under the Indenture, the Senior Subordinated Notes or any
     agreement executed by Borrower in connection therewith; (b) no Company has
     incurred (as defined in the Indenture) any Designated Senior Indebtedness
     (as defined in the Indenture) other than the Debt; and (c) no Company has
     "incurred" (as defined



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     in the Indenture) either prior to or after the granting of any Loan, any
     Indebtedness (as defined in the Indenture) in violation of Section 4.06
     (Limitation on Additional Indebtedness) of the Indenture.

     12. The Credit Agreement is hereby amended to delete Section 6.19 therefrom
and to insert in place thereof the following:

         SECTION 6.19. REVOLVING CREDIT FACILITY. This Agreement (a) constitutes
     "Revolving Credit Facility" (as defined in the 1999 Indenture), and (b) is
     a replacement of the Credit Agreement dated as of April 11, 1995, as
     amended, among Borrower, KeyBank National Association (successor by merger
     to Society National Bank), as Agent, and the banking institutions listed on
     Annex 1 attached thereto, and the Credit Agreement dated as of January 14,
     1998 among Borrower, KeyBank National Association, as Administrative Agent,
     The Huntington National Bank, as Co-Agent, and the banking institutions
     listed on Schedule 1 attached thereto.

     13. The Credit Agreement is hereby amended to delete Section 7.10 therefrom
and to insert in place thereof the following:

         SECTION 7.10. INDENTURE. If (a) any Event of Default (as defined in the
     Indenture), or any event or condition that with the lapse of time or giving
     of notice or both would constitute an Event of Default (as defined in the
     Indenture), shall exist under the Indenture, the Senior Subordinated Notes
     or any agreement executed by Borrower in connection therewith, (b) without
     the prior written consent of Agents and the Majority Banks, the Indenture
     or the Senior Subordinated Notes shall be amended or modified in any
     respect or replaced, or (c) the Senior Subordinated Notes shall be
     accelerated for any reason.

     14. The Credit Agreement is hereby amended to delete Section 8.4 therefrom
and to insert in place thereof the following:

         SECTION 8.4. EQUALIZATION PROVISION. Each Bank agrees with the other
     Banks that if it, at any time, shall obtain any Advantage over the other
     Banks or any thereof in respect of the Debt (except under Article III
     hereof), it shall purchase from the other Banks, for cash and at par, such
     additional participation in the Applicable Debt as shall be necessary to
     nullify the Advantage. If any such Advantage resulting in the purchase of
     an additional participation as aforesaid shall be recovered in whole or in
     part from the Bank receiving the Advantage, each such purchase shall be
     rescinded, and the purchase price restored (but without interest unless the
     Bank receiving the Advantage is required to pay interest on the Advantage
     to the Person recovering the Advantage from such Bank) to the extent of the
     recovery. Each Bank further agrees with the other Banks that if it at any
     time shall receive any payment for or on behalf of Borrower on any
     indebtedness owing by Borrower to that Bank by reason of offset of any
     deposit or other indebtedness, it will apply



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<PAGE>   10

     such payment first to the Debt owing by Borrower to that Bank (including,
     without limitation, any participation purchased or to be purchased pursuant
     to this Section or any other Section of this Agreement), subject to the
     Tranche D Conditions. Borrower agrees that any Bank so purchasing a
     participation from the other Banks or any thereof pursuant to this Section
     may exercise all its rights of payment (including the right of set-off)
     with respect to such participation as fully as if such Bank was a direct
     creditor of Borrower in the amount of such participation.

     15. The Credit Agreement is hereby amended to delete Section 9.9 therefrom
and to insert in place thereof the following:

         SECTION 9.9. INDEMNIFICATION OF AGENTS. The Banks agree to indemnify
     Agents (to the extent not reimbursed by Borrower), in accordance with their
     Commitment Percentages applicable to the Tranche A Commitments from and
     against any and all liabilities, obligations, losses, damages, penalties,
     actions, judgments, suits, costs, expenses or disbursements of any kind or
     nature whatsoever which may be imposed on, incurred by or asserted against
     Agents in their capacity as agent in any way relating to or arising out of
     this Agreement or any Loan Document or any action taken or omitted by
     Agents with respect to this Agreement or any Loan Document, provided that
     no Bank shall be liable for any portion of such liabilities, obligations,
     losses, damages, penalties, actions, judgments, suits, costs, expenses
     (including attorney fees) or disbursements resulting from Agents'
     respective gross negligence, willful misconduct or from any action taken or
     omitted by Agents, or either thereof, in any capacity other than as agent
     under this Agreement.

     16. The Credit Agreement is hereby amended to delete Section 10.13
therefrom and to insert in place thereof the following:

         SECTION 10.13. ENTIRE AGREEMENT. This Agreement, any Note and any other
     Loan Document or other agreement, document or instrument attached hereto or
     referred to herein or executed on or as of the Closing Date integrate all
     of the terms and conditions mentioned herein or incidental hereto and
     supersede all oral representations and negotiations and prior writings with
     respect to the subject matter hereof. This Agreement is intended to, and
     Borrower, Agents and the Banks agree that this Agreement shall, (a)
     constitute "Revolving Credit Facility" (as defined in the Indenture), and
     (b) be a replacement of the Credit Agreement dated as of April 11, 1995, as
     amended, among Borrower, KeyBank National Association (successor by merger
     to Society National Bank), as Agent, and the banking institutions listed on
     Annex 1 attached thereto, and the Credit Agreement dated as of January 14,
     1998 among Borrower, KeyBank National Association, as Administrative Agent,
     The Huntington National Bank, as Co-Agent, and the banking institutions
     listed on Schedule 1 attached thereto.



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     17. The Credit Agreement is hereby amended to delete SCHEDULE 1 and
SCHEDULE 2 thereof in their entirety and to insert in place thereof a new
SCHEDULE 1 and a new SCHEDULE 2, in the form of SCHEDULE 1 and SCHEDULE 2,
respectively, attached hereto.

     18. The Credit Agreement is hereby amended to add a new EXHIBIT F thereto
in the form of EXHIBIT F attached hereto.

     19. In connection with the fee specified in Section 2.8 of the Credit
Agreement, Borrower, Agents and the Banks agree that Borrower shall not be
obligated to pay the one-fourth percent (1/4%) increase fee set forth in such
Section 2.8 with respect to the increase of the Commitment as a result of the
addition of the Tranche D Commitments contemplated in this Second Amendment
Agreement, provided that nothing contained in this paragraph shall affect
Borrower's obligations with respect to the commitment fees relating to the
Tranche D Commitments set forth in subpart (f) of Section 2.5 of the Credit
Agreement (as amended by this Second Amendment Agreement).

     20. Concurrently with the execution of this Second Amendment Agreement,
Borrower shall:

     (a) execute and deliver to each Tranche D Bank a Tranche D Note dated as of
the Tranche D Closing Date, and such Tranche D Note shall be in the form and
substance of Exhibit F attached hereto;

     (b) pay to Administrative Agent, for the pro rata benefit of the Tranche D
Banks, a facility fee in the amount of One Hundred Sixty Thousand Dollars
($160,000);

     (c) deliver to Administrative Agent a Guaranty of Payment executed by each
of Columbia Nut & Bolt Corp., Geneva Rubber Company, Industrial Fasteners
Corporation, Integrated Logistics Solutions, Inc., Integrated Logistics Holding
Company, Park-Ohio Structural Hardware LLC, Pharmaceutical Logistics, Inc., and
Pharmacy Wholesale Logistics, Inc., together with such other corporate
governance and authorization documents as requested by Agents;

     (d) cause each Guarantor of Payment to consent and agree to and acknowledge
the terms of this Second Amendment Agreement; and

     (e) pay all legal fees and expenses of Administrative Agent in connection
with this Second Amendment Agreement.

     21. Borrower hereby represents and warrants to Agents and the Banks that
(a) Borrower has the legal power and authority to execute and deliver this
Second Amendment Agreement, (b) the officers executing this Second Amendment
Agreement have been duly authorized to execute and deliver the same and bind
Borrower with respect to the provisions hereof, (c) the execution and delivery
hereof by Borrower and the performance and observance by Borrower of the
provisions



                                       11
<PAGE>   12

hereof do not violate or conflict with the organizational agreements of Borrower
or any law applicable to Borrower or result in a breach of any provision of or
constitute a default under any other agreement, instrument or document binding
upon or enforceable against Borrower, (d) no Unmatured Event of Default or Event
of Default exists under the Credit Agreement, nor will any occur immediately
after the execution and delivery of this Second Amendment Agreement or by the
performance or observance of any provision hereof, (e) Borrower is not aware of
any claim or offset against, or defense or counterclaim to, any of Borrower's
obligations or liabilities under the Credit Agreement or any Related Writing,
and (f) this Second Amendment Agreement constitutes a valid and binding
obligation of Borrower in every respect, enforceable in accordance with its
terms.

     22. Each reference that is made in the Credit Agreement or any other
writing to the Credit Agreement shall hereafter be construed as a reference to
the Credit Agreement as amended hereby. Except as herein otherwise specifically
provided, all provisions of the Credit Agreement shall remain in full force and
effect and be unaffected hereby. This Second Amendment Agreement is a Related
Writing as defined in the Credit Agreement.

     23. Borrower and each Guarantor of Payment, by signing below, hereby waives
and releases Administrative Agent, Co-Agent and each of the Banks and the
respective directors, officers, employees, attorneys, affiliates and
subsidiaries of each of the foregoing from any and all claims, offsets, defenses
and counterclaims of which Borrower or such Guarantor of Payment is aware, such
waiver and release being with full knowledge and understanding of the
circumstances and effect thereof and after having consulted legal counsel with
respect thereto.

     24. This Second Amendment Agreement may be executed in any number of
counterparts, by different parties hereto in separate counterparts and by
facsimile signature, each of which when so executed and delivered shall be
deemed to be an original and all of which taken together shall constitute but
one and the same agreement.

     25. The rights and obligations of all parties hereto shall be governed by
the laws of the State of Ohio, without regard to principles of conflicts of
laws.

                  [Remainder of page intentionally left blank.]



                                       12
<PAGE>   13

     26. JURY TRIAL WAIVER. BORROWER, AGENTS AND EACH OF THE BANKS WAIVE ANY
RIGHT TO HAVE A JURY PARTICIPATE IN RESOLVING ANY DISPUTE, WHETHER SOUNDING IN
CONTRACT, TORT OR OTHERWISE, AMONG BORROWER, AGENTS AND THE BANKS, OR ANY
THEREOF, ARISING OUT OF, IN CONNECTION WITH, RELATED TO, OR INCIDENTAL TO THE
RELATIONSHIP ESTABLISHED AMONG THEM IN CONNECTION WITH THIS AGREEMENT OR ANY
NOTE OR OTHER INSTRUMENT, DOCUMENT OR AGREEMENT EXECUTED OR DELIVERED IN
CONNECTION HEREWITH OR THE TRANSACTIONS RELATED THERETO. THIS WAIVER SHALL NOT
IN ANY WAY AFFECT, WAIVE, LIMIT, AMEND OR MODIFY AGENTS' OR ANY BANK'S ABILITY
TO PURSUE REMEDIES PURSUANT TO ANY CONFESSION OF JUDGMENT OR COGNOVIT PROVISION
CONTAINED IN ANY NOTE OR OTHER INSTRUMENT, DOCUMENT OR AGREEMENT AMONG BORROWER,
AGENTS AND THE BANKS, OR ANY THEREOF.


                                 PARK-OHIO INDUSTRIES, INC.

                                     /s/ James S. Walker
                                 By: _______________________________
                                     James S. Walker, Vice President


                                     /s/ Ronald J. Cozean
                                 and _______________________________
                                       Ronald J. Cozean, Secretary



                                 KEYBANK NATIONAL ASSOCIATION,
                                  as a Bank and as Administrative Agent

                                     /s/ Kenneth M. Merhar
                                 By: __________________________________
                                     Kenneth M. Merhar, Vice President



                                 THE HUNTINGTON NATIONAL BANK,
                                  as a Bank and as Co-Agent

                                   /s/ Timothy M. Ward
                               By: ____________________________________
                                     Timothy M. Ward, Vice President



                                       13
<PAGE>   14

<TABLE>
<CAPTION>
                                                        SCHEDULE 1

-------------------------------------------------------------------------------------------------------------------------------
       BANKING        TRANCHE A       TRANCHE B       TRANCHE C      TRANCHE A       TRANCHE D       TRANCHE D       MAXIMUM
    INSTITUTIONS      COMMITMENT      COMMITMENT      COMMITMENT      THROUGH       COMMITMENT      COMMITMENT       AMOUNT
                        AMOUNT          AMOUNT          AMOUNT       TRANCHE C        AMOUNT        PERCENTAGE
                                                                    COMMITMENT
                                                                    PERCENTAGE
-------------------------------------------------------------------------------------------------------------------------------
<S>                 <C>              <C>            <C>             <C>             <C>             <C>           <C>
KeyBank              $50,000,000     $12,500,000     $12,500,000       50%          $25,000,000        100%        $100,000,000
National
Association
-------------------------------------------------------------------------------------------------------------------------------
The Huntington       $50,000,000     $12,500,000     $12,500,000       50%               $0             0%         $75,000,000
National Bank
-------------------------------------------------------------------------------------------------------------------------------
Total               $100,000,000     $25,000,000     $25,000,000       100%         $25,000,000        100%
-------------------------------------------------------------------------------------------------------------------------------
Total                                                                                                             $175,000,000
Commitment
Amount
-------------------------------------------------------------------------------------------------------------------------------
</TABLE>



                                       14

<PAGE>   15

                                   SCHEDULE 2

                              GUARANTORS OF PAYMENT


Advance Vehicles, Inc.
Blue Falcon Forge, Inc.
Castle Rubber Company
Cicero Flexible Products, Inc.
Columbia Nut & Bolt Corp.
GIS Industries, Inc. (formerly known as Charken Company, Inc.)
General Aluminum Manufacturing Company II
General Aluminum Mfg. Company
Geneva Rubber Company
Industrial Fasteners Corporation
Integrated Logistics Solutions, Inc.
Integrated Logistics Solutions LLC (successor by merger to Arden Industrial
  Products, Inc.)
Integrated Logistics Holding Company
Kay Home Products, Inc.
Park-Ohio Structural Hardware LLC
Pharmaceutical Logistics, Inc.
Pharmacy Wholesale Logistics, Inc.
RB&W Manufacturing LLC (successor by merger to RB&W Corporation)
The Ajax Manufacturing Company
The Metalloy Corporation
Tocco, Inc.



                                       15
<PAGE>   16

                                    EXHIBIT F

                                 TRANCHE D NOTE

$__________________                                              Cleveland, Ohio
                                                                November 1, 1999


     FOR VALUE RECEIVED, the undersigned, PARK-OHIO INDUSTRIES, INC.
("Borrower") promises to pay on the last day of the Commitment Period, as
defined in the Credit Agreement (as hereinafter defined), to the order of
_______________________ ("Bank") at the Main Office of KEYBANK NATIONAL
ASSOCIATION, as Administrative Agent, 127 Public Square, Cleveland, Ohio
44114-1306 the principal sum of


 ......................................................................   DOLLARS


or the aggregate unpaid principal amount of all Tranche D Loans made by Bank to
Borrower pursuant to Section 2.1D of the Credit Agreement, whichever is less, in
lawful money of the United States of America. As used herein, "Credit Agreement"
means the Amended and Restated Credit Agreement dated as of November 2, 1998, as
amended, among Borrower, the banks named therein, KeyBank National Association,
as Administrative Agent, and The Huntington National Bank, as Co- Agent, as the
same may from time to time be further amended, restated or otherwise modified.
Capitalized terms used herein shall have the meanings ascribed to them in the
Credit Agreement.

     Borrower also promises to pay interest on the unpaid principal amount of
each Tranche D Loan from time to time outstanding, from the date of such
Tranche D Loan until the payment in full thereof, at the rates per annum which
shall be determined in accordance with the provisions of Section 2.1D of the
Credit Agreement. Such interest shall be payable on each date provided for in
such Section 2.1D; provided, however, that interest on any principal portion
which is not paid when due shall be payable on demand.

     The portions of the principal sum hereof from time to time representing
Prime Rate Loans and LIBOR Loans, and payments of principal of any thereof, will
be shown on the records of Bank by such method as Bank may generally employ;
provided, however, that failure to make any such entry shall in no way detract
from Borrower's obligations under this Note.

     If this Note shall not be paid at maturity, whether such maturity occurs by
reason of lapse of time or by operation of any provision for acceleration of
maturity contained in the Credit Agreement, the principal hereof and the unpaid
interest thereon shall bear interest, until paid, at a rate per annum which
shall be the Default Rate. All payments of principal of and interest on this
Note shall be made in immediately available funds. In the event of a failure to
pay interest or principal, when the same becomes due, Bank may collect and
Borrower agrees to pay a late charge of an amount equal to the greater of
(a) ten percent (10%) of the amount of such late payment, or (b) Twenty Five
Dollars ($25).



                                       16
<PAGE>   17

     This Note is one of the Tranche D Notes referred to in the Credit
Agreement. Reference is made to the Credit Agreement for a description of the
right of the undersigned to anticipate payments hereof, the right of the holder
hereof to declare this Note due prior to its stated maturity, and other terms
and conditions upon which this Note is issued.

     Except as expressly provided in the Credit Agreement, Borrower expressly
waives presentment, demand, protest and notice of any kind.

     The undersigned authorizes any attorney at law at any time or times after
the maturity hereof (whether maturity occurs by lapse of time or by
acceleration) to appear in any state or federal court of record in the United
States of America, to waive the issuance and service of process, to admit the
maturity of this Note and the nonpayment thereof when due, to confess judgment
against the undersigned in favor of the holder of this Note for the amount then
appearing due, together with interest and costs of suit, and thereupon to
release all errors and to waive all rights of appeal and stay of execution. The
foregoing warrant of attorney shall survive any judgment, and if any judgment be
vacated for any reason, the holder hereof nevertheless may thereafter use the
foregoing warrant of attorney to obtain an additional judgment or judgments
against the undersigned. The undersigned agrees that Agents' or the Banks'
attorney may confess judgment pursuant to the foregoing warrant of attorney. The
undersigned further agrees that the attorney confessing judgment pursuant to the
foregoing warrant of attorney may receive a legal fee or other compensation from
Agents or the Banks.

                                       PARK-OHIO INDUSTRIES, INC.


                                       By: _______________________________
                                           James S. Walker, Vice President



                                       and _______________________________
                                           Ronald J. Cozean, Secretary



================================================================================
"WARNING -- BY SIGNING THIS PAPER YOU GIVE UP YOUR RIGHT TO NOTICE AND COURT
TRIAL. IF YOU DO NOT PAY ON TIME A COURT JUDGMENT MAY BE TAKEN AGAINST YOU
WITHOUT YOUR PRIOR KNOWLEDGE AND THE POWERS OF A COURT CAN BE USED TO COLLECT
FROM YOU REGARDLESS OF ANY CLAIMS YOU MAY HAVE AGAINST THE CREDITOR WHETHER FOR
RETURNED GOODS, FAULTY GOODS, FAILURE ON HIS PART TO COMPLY WITH THE AGREEMENT
OR ANY OTHER CAUSE."
================================================================================



                                       17
<PAGE>   18

                            GUARANTOR ACKNOWLEDGMENT
                            ------------------------

     Each of the undersigned consents and agrees to and acknowledges the terms
of the foregoing Second Amendment Agreement. Each of the undersigned further
agrees that the obligations of the undersigned pursuant to the Guaranty of
Payment executed by the undersigned shall remain in full force and effect and be
unaffected hereby.

                               ADVANCE VEHICLES, INC.
                               INTEGRATED LOGISTICS SOLUTIONS
                                  LLC (successor by merger to
                                  Arden Industrial Products, Inc.)
                               BLUE FALCON FORGE, INC.
                               CASTLE RUBBER COMPANY
                               GIS INDUSTRIES, INC.,
                                  (formerly known as Charken Company, Inc.)
                               CICERO FLEXIBLE PRODUCTS, INC.
                               GENERAL ALUMINUM MANUFACTURING COMPANY II
                               GENERAL ALUMINUM MFG. COMPANY
                               KAY HOME PRODUCTS, INC.
                               RB&W MANUFACTURING LLC (successor
                                  by merger to RB&W Corporation)
                               THE AJAX MANUFACTURING COMPANY
                               TOCCO, INC.
                               THE METALLOY CORPORATION


                                   /s/ James S. Walker
                               By: ____________________________________
                                   James S. Walker, Vice President
                                   of each of the foregoing Companies


                                   /s/ Ronald J. Cozean
                               By: ___________________________________
                                   Ronald J. Cozean, Secretary
                                   of each of the foregoing Companies



                                       18