-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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 n20wVKU0ceUs0c/e21UK2A==

<SEC-DOCUMENT>0001269873-05-000001.txt : 20050729
<SEC-HEADER>0001269873-05-000001.hdr.sgml : 20050729
<ACCEPTANCE-DATETIME>20050729114304
ACCESSION NUMBER:		0001269873-05-000001
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20050728
FILED AS OF DATE:		20050729
DATE AS OF CHANGE:		20050729

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			METALDYNE CORP
		CENTRAL INDEX KEY:			0000745448
		STANDARD INDUSTRIAL CLASSIFICATION:	MOTOR VEHICLE PARTS & ACCESSORIES [3714]
		IRS NUMBER:				382513957
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		47659 HALYARD DRIVE
		CITY:			PLYMOUTH
		STATE:			MI
		ZIP:			48170
		BUSINESS PHONE:		734-207-6200

	MAIL ADDRESS:	
		STREET 1:		47659 HALYARD DRIVE
		CITY:			PLYMOUTH
		STATE:			MI
		ZIP:			48170

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MASCOTECH INC
		DATE OF NAME CHANGE:	19930629

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MASCO INDUSTRIES INC
		DATE OF NAME CHANGE:	19930629

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			AMATO THOMAS A
		CENTRAL INDEX KEY:			0001269873

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-12068
		FILM NUMBER:		05983412

	BUSINESS ADDRESS:	
		STREET 1:		C/O METALDYNE CORP
		STREET 2:		47603 HALYARD DR
		CITY:			PLYMOUTH
		STATE:			MI
		ZIP:			48170
		BUSINESS PHONE:		7342076200
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-07-28</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000745448</issuerCik>
        <issuerName>METALDYNE CORP</issuerName>
        <issuerTradingSymbol>None</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001269873</rptOwnerCik>
            <rptOwnerName>AMATO THOMAS A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O METALDYNE CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>47603 HALYARD DRIVE</rptOwnerStreet2>
            <rptOwnerCity>PLYMOUTH</rptOwnerCity>
            <rptOwnerState>MI</rptOwnerState>
            <rptOwnerZipCode>48170</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EVP, Commercial Operations</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Employee Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>6.5</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2005-07-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>54078</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2015-07-28</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>54078</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>97704</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The option vests in three equal annual installments beginning on May 1, 2006.</footnote>
        <footnote id="F2">Awarded pursuant to the Metaldyne 2001 Long Term Incentive Plan.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Thomas A. Amato</signatureName>
        <signatureDate>2005-07-29</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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