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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0001140361-08-007859.txt : 20080327
<SEC-HEADER>0001140361-08-007859.hdr.sgml : 20080327
<ACCEPTANCE-DATETIME>20080327183058
ACCESSION NUMBER:		0001140361-08-007859
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080325
FILED AS OF DATE:		20080327
DATE AS OF CHANGE:		20080327

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			WD 40 CO
		CENTRAL INDEX KEY:			0000105132
		STANDARD INDUSTRIAL CLASSIFICATION:	MISCELLANEOUS CHEMICAL PRODUCTS [2890]
		IRS NUMBER:				951797918
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0831

	BUSINESS ADDRESS:	
		STREET 1:		1061 CUDAHY PL
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92110
		BUSINESS PHONE:		6192751400

	MAIL ADDRESS:	
		STREET 1:		1061 CUDAHY PLACE
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92110

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			IRWIN MICHAEL J
		CENTRAL INDEX KEY:			0001191648

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-06936
		FILM NUMBER:		08716281

	MAIL ADDRESS:	
		STREET 1:		228 WINTERHAWK LN
		CITY:			ENCINITAS
		STATE:			CA
		ZIP:			92024
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-03-25</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000105132</issuerCik>
        <issuerName>WD 40 CO</issuerName>
        <issuerTradingSymbol>WDFC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001191648</rptOwnerCik>
            <rptOwnerName>IRWIN MICHAEL J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1061 CUDAHY PLACE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SAN DIEGO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92110</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Executive Vice President/CFO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2008-03-25</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3971</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10062</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Restricted Stock Units (Common Stock equivalents) were granted pursuant to the WD-40 Company 2007 Stock Incentive Plan in exchange for the termination of the reporting person's Supplemental Retirement Benefit Plan agreement.  The Restricted Stock Units will be settled solely with Issuer Common Stock upon termination of the reporting person's employment.  Shares are vested at the following schedule: 1324 on 3/25/09, 1324 on 3/25/10, 1323 on 3/25/11.  Upon termination of employment, only vested shares will be issued.</footnote>
        <footnote id="F2">Total includes 691 shares held in WD-40 Company Profit Sharing Plan (Company Stock Fund) account; estimated number of shares based upon equivalent value of units held.  Total also includes 3971 Restricted Stock Units.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Michael J Irwin</signatureName>
        <signatureDate>2008-03-27</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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