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                                                                   EXHIBIT 10(t)

                   FOURTH AMENDED AND RESTATED PROMISSORY NOTE


Date: January 31, 2001
Amount:  $5,500,000.00

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<S>                                                        <C>
Bank:                                                      Borrower:
The Chase Manhattan Bank (successor by merger to Chase     Peerless Mfg. Co.
Bank of Texas, National Association)                       2819 Walnut Hill Lane
12875 Josey Lane                                           Dallas, Texas  75229
Dallas, Texas  75234-6398
County:  Dallas                                            County:  Dallas
</TABLE>
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FOR VALUE RECEIVED, the undersigned Borrower unconditionally (and jointly and
severally, if more than one) promises to pay to the order of Bank, its
successors and assigns, without setoff, at its offices indicated at the
beginning of this third amended and restated promissory note ("Note"), or at
such other place as may be designated by Bank, the principal amount of Five
Million Five Hundred Thousand Dollars ($5,500,000.00), or so much thereof as may
be advanced in immediately available funds, together with interest computed
daily on the outstanding principal balance hereunder, at an annual interest
rate, and in accordance with the payment schedule, indicated below.

16.  LOAN AGREEMENT. This Note is executed and delivered by Borrower pursuant to
     the certain Second Amended and Restated Loan Agreement dated as of December
     12, 1998 between Borrower and Bank (as the same has been amended pursuant
     to that certain Waiver and First Amendment to Second Amended and Restated
     Loan Agreement dated December 12, 1999, that certain Consent Letter dated
     as of February 25, 2000, that certain Third Amendment to Second Amended and
     Restated Loan Agreement dated June 2, 2000, that certain Waiver Letter
     dated as of December 1, 2000, and as the same may hereinafter be amended or
     otherwise modified, herein called the "Loan Agreement") and is the Note as
     defined therein. All terms defined in the Loan Agreement, wherever used
     herein, shall have the same meanings as are prescribed by the Loan
     Agreement.

17.  RATE. The unpaid principal from day to day outstanding under this Note
     shall bear interest at the applicable rate prescribed for the Loans as
     provided by the Loan Agreement. Bank's records shall be conclusive proof of
     loans, payments and interest accruals hereunder, absent proof by Borrower
     of error. Notwithstanding any provision of this Note, Bank does not intend
     to charge and Borrower shall not be required to pay any amount of interest
     or other charges in excess of the maximum permitted by applicable law.
     Borrower agrees that during the full term hereof, the maximum lawful
     interest rate for this Note as determined under Texas law shall be the
     weekly rate ceiling described in, and computed in accordance with the Texas
     Finance Code. Further, to the extent that any other lawful rate ceiling
     exceeds the rate ceiling so determined then the higher rate ceiling shall
     apply. Any payment in excess of such maximum shall be refunded to Borrower
     or credited against principal, at the option of Bank.

18.  REPAYMENT. Subject to the terms of the Loan Agreement, all unpaid principal
     and accrued interest under this Note shall be payable as follows: Accrued
     interest shall be payable quarterly in arrears on each Interest Payment
     Date beginning on March 31, 2001 and continuing thereafter through the
     Termination Date, and all unpaid principal hereunder and all other amounts
     payable hereunder relative to the Loans, shall be due and payable to Bank
     in full, and the Line shall terminate, on the Termination Date. To the
     extent that any accrued interest is not paid on the date when due, as
     provided herein, Bank may at its option (but with no obligation to do so),
     add the amount of such accrued interest to the unpaid principal due by
     Borrower under the Loans, in which event such amount will be deemed paid
     and the aggregate amount thereof shall be treated as a Loan.


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19.  REVOLVING FEATURE. Borrower may borrow, repay and reborrow hereunder at any
     time, up to a maximum aggregate amount outstanding at any one time equal to
     the principal amount of this Note, provided that Borrower is not in default
     under any provision of this Note, any other documents executed in
     connection with this Note, or any other note or other loan documents now or
     hereafter executed in connection with any other obligation of Borrower to
     Bank, and provided that the borrowings hereunder do not exceed any
     borrowing base or other limitation on borrowings by Borrower, including,
     without limitation, those set forth in the Loan Agreement. Bank shall incur
     no liability for its refusal to advance funds based upon its determination
     that any conditions of such further advances have not been met. Bank
     records of the amounts borrowed from time to time shall be conclusive proof
     thereof.

20.  WAIVERS, CONSENTS AND COVENANTS. Borrower, any indorser or guarantor
     hereof, or any other party hereto (individually an "Obligor" and
     collectively "Obligors") and each of them jointly and severally: (a) waive
     presentment, demand, protest, notice of demand, notice of intent to
     accelerate, notice of acceleration of maturity, notice of protest, notice
     of nonpayment, notice of dishonor, and any other notice required to be
     given under the law to any Obligor in connection with the delivery,
     acceptance, performance, default or enforcement of this Note, any
     indorsement or guaranty of this Note or any other documents executed in
     connection with this Note or any other note or other loan documents now or
     hereafter executed in connection with any obligation of Borrower to Bank
     (the "Loan Documents"); (b) consent to all delays, extensions, renewals or
     other modifications of this Note or the Loan Documents, or waivers of any
     term hereof or of the Loan Documents, or release or discharge by Bank of
     any of Obligors, or release, substitution or exchange of any security for
     the payment hereof, or the failure to act on the part of Bank, or any
     indulgence shown by Bank (without notice to or further assent from any of
     Obligors), and agree that no such action, failure to act or failure to
     exercise any right or remedy by Bank shall in any way affect or impair the
     obligations of any Obligors or be construed as a waiver by Bank of, or
     otherwise affect, any of Bank's rights under this Note, under any
     indorsement or guaranty of this Note or under any of the Loan Documents;
     and (c) agree to pay, on demand, all costs and expenses of collection or
     defense of this Note or of any indorsement or guaranty hereof and/or the
     enforcement or defense of Bank's rights with respect to, or the
     administration, supervision, preservation, or protection of, or realization
     upon, any property securing payment hereof, including, without limitation,
     reasonable attorney's fees, including fees related to any suit, mediation
     or arbitration proceeding, out of court payment agreement, trial, appeal,
     bankruptcy proceedings or other proceeding, in such amount as may be
     determined reasonable by any arbitrator or court, whichever is applicable.

21.  PREPAYMENTS. Any prepayments of the Loans outstanding under this Note are
     subject to the terms contained in the Loan Agreement.

22.  EVENTS OF DEFAULT. The following are events of default hereunder: (a) any
     default under the Loan Agreement; (b) the commencement of a proceeding
     against any Obligor for dissolution or liquidation, the voluntary or
     involuntary termination or dissolution of any Obligor or the merger or
     consolidation of any Obligor with or into another entity; and (c) the
     insolvency of, the business failure of, the appointment of a custodian,
     trustee, liquidator or receiver for or for any of the property of, the
     assignment for the benefit of creditors by, or the filing of a petition
     under bankruptcy, insolvency or debtor's relief law or the filing of a
     petition for any adjustment of indebtedness, composition or extension by or
     against any Obligor.

23.  REMEDIES UPON DEFAULT. Whenever there is a default under this Note (a) the
     entire balance outstanding hereunder and all other obligations of any
     Obligor to Bank (however acquired or evidenced) shall, at the option of
     Bank, become immediately due and payable and any obligation of Bank to
     permit further borrowing under this Note shall immediately cease and
     terminate, and/or (b) to the extent permitted by law, the Rate of interest
     on the unpaid principal shall be increased at Bank's discretion up to the
     maximum rate allowed by law, or if none, 25% per annum (the "Default
     Rate"). The provisions herein for a Default Rate shall not be deemed to
     extend the time for any payment hereunder or to constitute a "grace period"
     giving Obligors a right to cure any default. At Bank's


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     option, any accrued and unpaid interest, fees or charges may, for purposes
     of computing and accruing interest on a daily basis after the due date of
     the Note or any installment thereof, be deemed to be a part of the
     principal balance, and interest shall accrue on a daily compounded basis
     after such date at the Default Rate provided in this Note until the entire
     outstanding balance of principal and interest is paid in full. Upon a
     default under this Note, Bank is hereby authorized at any time, at its
     option and without notice or demand, to set off and charge against any
     deposit accounts of any Obligor (as well as any money, instruments,
     securities, documents, chattel paper, credits, claims, demands, income and
     any other property, rights and interests of any Obligor), which at any time
     shall come into the possession or custody or under the control of Bank or
     any of its agents, affiliates or correspondents, any and all obligations
     due hereunder. Additionally, Bank shall have all rights and remedies
     available under each of the Loan Documents (as defined in the Loan
     Agreement), as well as all rights and remedies available at law or in
     equity.

24.  NON-WAIVER. The failure at any time of Bank to exercise any of its options
     or any other rights hereunder shall not constitute a waiver thereof, nor
     shall it be a bar to the exercise of any of its options or rights at a
     later date. All rights and remedies of Bank shall be cumulative and may be
     pursued singly, successively or together, at the option of Bank. The
     acceptance by Bank of any partial payment shall not constitute a waiver of
     any default or of any of Bank's rights under this Note. No waiver of any of
     its rights hereunder, and no modification or amendment of this Note, shall
     be deemed to be made by Bank unless the same shall be in writing, duly
     signed on behalf of Bank; each such waiver shall apply only with respect to
     the specific instance involved, and shall in no way impair the rights of
     Bank or the obligations of Obligors to Bank in any other respect at any
     other time.

25.  APPLICABLE LAW, VENUE AND JURISDICTION. Borrower agrees that this Note
     shall be deemed to have been made in the State of Texas at Bank's address
     indicated at the beginning of this Note and shall be governed by, and
     construed in accordance with, the laws of the State of Texas and is
     performable in the City and County of Texas indicated at the beginning of
     this Note. In any litigation in connection with or to enforce this Note or
     any indorsement or guaranty of this Note or any Loan Documents, Obligors,
     and each of them, irrevocably consent to and confer personal jurisdiction
     on the courts of the State of Texas or the United States courts located
     within the State of Texas. Nothing contained herein shall, however, prevent
     Bank from bringing any action or exercising any rights within any other
     state or jurisdiction or from obtaining personal jurisdiction by any other
     means available under applicable law.

26.  PARTIAL INVALIDITY. The unenforceability or invalidity of any provision of
     this Note shall not affect the enforceability or validity of any other
     provision herein and the invalidity or unenforceability of any provision of
     this Note or of the Loan Documents to any person or circumstance shall not
     affect the enforceability or validity of such provision as it may apply to
     other persons or circumstances.

27.  BINDING EFFECT. This Note shall be binding upon and inure to the benefit of
     Borrower, Obligors and Bank and their respective successors, assigns, heirs
     and personal representatives, provided, however, that no obligations of
     Borrower or Obligors hereunder can be assigned without prior written
     consent of Bank.

28.  AMENDMENT AND RESTATEMENT OF PREVIOUS NOTES. This Note is in renewal,
     increase and extension of, and is issued in amendment and restatement of
     (but not in extinguishment of) the indebtedness evidenced by the certain
     Third Amended and Restated Promissory Note dated December 12, 2000,
     previously executed and delivered by Borrower payable to the order of Chase
     Bank of Texas, National Association (now known as "The Chase Manhattan
     Bank") in the face amount of $5,500,000.00 (the "Amended and Restated
     Note") which Amended and Restated Note was in renewal and extension of, and
     issued in amendment and restatement of (but not in extinguishment of) the
     indebtedness previously evidenced by the Second Amended and Restated
     Promissory Note dated December 12, 1999, previously executed and delivered
     by Borrower payable to the order of Bank in the face amount of
     $3,500,000.00, that certain amended and restated promissory note dated
     December 28, 1998 previously executed and delivered by Borrower payable to
     the order of Bank in the face amount of $3,500,000.00, and that certain
     Promissory Note dated January 12, 1998, previously



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     executed and delivered by Borrower payable to the order of Texas Commerce
     Bank National Association (now known as "Chase Bank of Texas, National
     Association"), in the face amount of $2,500,000.00 and all such
     indebtedness hereafter shall be governed by and payable in accordance with
     the terms hereof. Borrower agrees to pay all unpaid interest accrued under
     the Amended and Restated Note as of the date hereof on the next Interest
     Payment Date.

29.  CONTROLLING DOCUMENT. To the extent that this Note conflicts with or is in
     any way incompatible with any other document related specifically to the
     loan evidenced by this Note, this Note shall control over any other such
     document, and if this Note does not address an issue, then each other such
     document shall control to the extent that it deals most specifically with
     an issue.

30.  ARBITRATION. ANY CONTROVERSY OR CLAIM BETWEEN OR AMONG THE PARTIES HERETO
     INCLUDING BUT NOT LIMITED TO THOSE ARISING OUT OF OR RELATING TO THIS
     INSTRUMENT, AGREEMENT OR DOCUMENT OR ANY RELATED INSTRUMENTS, AGREEMENTS OR
     DOCUMENTS, INCLUDING ANY CLAIM BASED ON OR ARISING FROM AN ALLEGED TORT,
     SHALL BE DETERMINED BY BINDING ARBITRATION IN ACCORDANCE WITH THE FEDERAL
     ARBITRATION ACT (OR IF NOT APPLICABLE, THE APPLICABLE STATE LAW), THE RULES
     OF PRACTICE AND PROCEDURE FOR THE ARBITRATION OF COMMERCIAL DISPUTES OF
     J.A.M.S./ ENDISPUTE OR ANY SUCCESSOR THEREOF ("J.A.M.S."), AND THE "SPECIAL
     RULES" SET FORTH BELOW. IN THE EVENT OF ANY INCONSISTENCY, THE SPECIAL
     RULES SHALL CONTROL. JUDGMENT UPON ANY ARBITRATION AWARD MAY BE ENTERED IN
     ANY COURT HAVING JURISDICTION. ANY PARTY TO THIS INSTRUMENT, AGREEMENT OR
     DOCUMENT MAY BRING AN ACTION, INCLUDING A SUMMARY OR EXPEDITED PROCEEDING,
     TO COMPEL ARBITRATION OF ANY CONTROVERSY OR CLAIM TO WHICH THIS AGREEMENT
     APPLIES IN ANY COURT HAVING JURISDICTION OVER SUCH ACTION.

                  A. SPECIAL RULES. THE ARBITRATION SHALL BE CONDUCTED IN THE
         COUNTY OF ANY BORROWER'S DOMICILE AT THE TIME OF THE EXECUTION OF THIS
         INSTRUMENT, AGREEMENT OR DOCUMENT AND ADMINISTERED BY J.A.M.S. WHO WILL
         APPOINT AN ARBITRATOR; IF J.A.M.S. IS UNABLE OR LEGALLY PRECLUDED FROM
         ADMINISTERING THE ARBITRATION, THEN THE AMERICAN ARBITRATION
         ASSOCIATION WILL SERVE. ALL ARBITRATION HEARINGS WILL BE COMMENCED
         WITHIN 90 DAYS OF THE DEMAND FOR ARBITRATION; FURTHER, THE ARBITRATOR
         SHALL ONLY, UPON A SHOWING OF CAUSE, BE PERMITTED TO EXTEND THE
         COMMENCEMENT OF SUCH HEARING FOR UP TO AN ADDITIONAL 60 DAYS.

                  B. RESERVATION OF RIGHTS. NOTHING IN THIS ARBITRATION
         PROVISION SHALL BE DEEMED TO (I) LIMIT THE APPLICABILITY OF ANY
         OTHERWISE APPLICABLE STATUTES OF LIMITATION OR REPOSE AND ANY WAIVERS
         CONTAINED IN THIS INSTRUMENT, AGREEMENT OR DOCUMENT; OR (II) BE A
         WAIVER BY BANK OF THE PROTECTION AFFORDED TO IT BY 12 U.S.C. SEC. 91 OR
         ANY SUBSTANTIALLY EQUIVALENT STATE LAW; OR (III) LIMIT THE RIGHT OF
         BANK HERETO (A) TO EXERCISE SELF HELP REMEDIES SUCH AS (BUT NOT LIMITED
         TO) SETOFF, OR (B) TO FORECLOSE AGAINST ANY REAL OR PERSONAL PROPERTY
         COLLATERAL, OR (C) TO OBTAIN FROM A COURT PROVISIONAL OR ANCILLARY
         REMEDIES SUCH AS (BUT NOT LIMITED TO) INJUNCTIVE RELIEF, WRIT OF
         POSSESSION OR THE APPOINTMENT OF A RECEIVER. BANK MAY EXERCISE SUCH
         SELF HELP RIGHTS, FORECLOSE UPON SUCH PROPERTY, OR OBTAIN SUCH
         PROVISIONAL OR ANCILLARY REMEDIES BEFORE, DURING OR AFTER THE PENDENCY
         OF ANY ARBITRATION PROCEEDING BROUGHT PURSUANT TO THIS INSTRUMENT,
         AGREEMENT OR DOCUMENT. NEITHER THIS EXERCISE OF SELF HELP REMEDIES NOR
         THE INSTITUTION OR MAINTENANCE OF AN ACTION FOR FORECLOSURE OR
         PROVISIONAL OR ANCILLARY REMEDIES SHALL CONSTITUTE A


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          WAIVER OF THE RIGHT OF ANY PARTY, INCLUDING THE CLAIMANT IN ANY SUCH
          ACTION, TO ARBITRATE THE MERITS OF THE CONTROVERSY OR CLAIM
          OCCASIONING RESORT TO SUCH REMEDIES.

Borrower represents to Bank that the proceeds of this loan are to be used
primarily for business, commercial or agricultural purposes. Borrower
acknowledges having read and understood, and agrees to be bound by, all terms
and conditions of this Note.

NOTICE OF FINAL AGREEMENT:

THIS WRITTEN PROMISSORY NOTE REPRESENTS THE FINAL AGREEMENT BETWEEN THE PARTIES,
AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT
ORAL AGREEMENTS OF THE PARTIES. THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN
THE PARTIES.

<TABLE>
<S>                                             <C>
Bank: THE CHASE MANHATTAN BANK                  Borrower: PEERLESS MFG. CO.

By: /s/                                         By: /s/
    -----------------------------------             -----------------------------------
    Michael B. Phillips, Vice President             Sherrill Stone, Chairman and
                                                    Chief Executive Officer
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