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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 PZ0UFWc+yTM0RQyO/5YBsRsHHSzjfNNf/qzRL1BB+nWkRxyY/1fhcsJFQl/YmV2V
 kMkp1SS0c/3E/NN/CZr99w==

<SEC-DOCUMENT>0001179110-04-007459.txt : 20040405
<SEC-HEADER>0001179110-04-007459.hdr.sgml : 20040405
<ACCEPTANCE-DATETIME>20040405151658
ACCESSION NUMBER:		0001179110-04-007459
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20040402
FILED AS OF DATE:		20040405

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			STEWART & STEVENSON SERVICES INC
		CENTRAL INDEX KEY:			0000094328
		STANDARD INDUSTRIAL CLASSIFICATION:	ENGINES & TURBINES [3510]
		IRS NUMBER:				741051605
		STATE OF INCORPORATION:			TX
		FISCAL YEAR END:			0131

	BUSINESS ADDRESS:	
		STREET 1:		2707 N LOOP W
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77008
		BUSINESS PHONE:		7138687700

	MAIL ADDRESS:	
		STREET 1:		P O BOX 1637
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77251-1637

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			STEVENSON DONALD E
		CENTRAL INDEX KEY:			0001076388

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-11443
		FILM NUMBER:		04717221

	BUSINESS ADDRESS:	
		STREET 1:		P O BOX 1637
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77251
		BUSINESS PHONE:		7137848667

	MAIL ADDRESS:	
		STREET 1:		P O BOX 1637
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77251
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-04-02</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000094328</issuerCik>
        <issuerName>STEWART &amp; STEVENSON SERVICES INC</issuerName>
        <issuerTradingSymbol>SVC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001076388</rptOwnerCik>
            <rptOwnerName>STEVENSON DONALD E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>P. O. BOX 1637</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77251-1637</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Vice President</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>common stock</value>
            </securityTitle>
            <transactionDate>
                <value>2004-04-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>80000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>15.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>304176</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>common stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>940</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Trust</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">This sale was effected pursuant to a 10b5-1 sales plan adopted by the reporting person.</footnote>
        <footnote id="F2">Shares held by Donald E. Stevenson Trust</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Rita Schaulat, attorney-in-fact for Donald E. Stevenson</signatureName>
        <signatureDate>2004-04-05</signatureDate>
    </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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