-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 GoDMUEdYEHxA/3Dkfojl8ttIVyWR6ZJETkhAmmCF8wReXP64BCMEaQYu9mEXHuqT
 SPsKdiGSMGSuKJ+MspcLKQ==

<SEC-DOCUMENT>0000807249-06-000159.txt : 20060526
<SEC-HEADER>0000807249-06-000159.hdr.sgml : 20060526
<ACCEPTANCE-DATETIME>20060526105443
ACCESSION NUMBER:		0000807249-06-000159
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060525
FILED AS OF DATE:		20060526
DATE AS OF CHANGE:		20060526

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			AMPCO PITTSBURGH CORP
		CENTRAL INDEX KEY:			0000006176
		STANDARD INDUSTRIAL CLASSIFICATION:	PUMPS & PUMPING EQUIPMENT [3561]
		IRS NUMBER:				251117717
		STATE OF INCORPORATION:			PA
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		600 GRANT ST STE 4600
		CITY:			PITTSBURGH
		STATE:			PA
		ZIP:			15219
		BUSINESS PHONE:		4124564400

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	SCREW & BOLT CORP OF AMERICA
		DATE OF NAME CHANGE:	19710518

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GGCP, INC.
		CENTRAL INDEX KEY:			0001238894
		STATE OF INCORPORATION:			NY
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-00898
		FILM NUMBER:		06869151

	BUSINESS ADDRESS:	
		STREET 1:		ONE CORPORATE CENTER
		CITY:			RYE
		STATE:			NY
		ZIP:			10580
		BUSINESS PHONE:		9149215100

	MAIL ADDRESS:	
		STREET 1:		140 GREENWICH AVENUE
		CITY:			GREENWICH
		STATE:			CT
		ZIP:			06830

	FORMER NAME:	
		FORMER CONFORMED NAME:	GABELLI GROUP CAPITAL PARTNERS INC
		DATE OF NAME CHANGE:	20030604

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GABELLI MARIO J
		CENTRAL INDEX KEY:			0001185533

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-00898
		FILM NUMBER:		06869152

	BUSINESS ADDRESS:	
		STREET 1:		C/O GABELLI ASSET MANAGEMENT INC
		STREET 2:		ONE CORPORATE CENTER
		CITY:			RYE
		STATE:			NY
		ZIP:			16580
		BUSINESS PHONE:		9149215017

	MAIL ADDRESS:	
		STREET 1:		C/O GABELLI ASSET MANAGEMENT INC
		STREET 2:		ONE CORPORATE CENTER
		CITY:			RYE
		STATE:			NY
		ZIP:			10580

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GAMCO INVESTORS, INC. ET AL
		CENTRAL INDEX KEY:			0000807249
		STATE OF INCORPORATION:			NY
		FISCAL YEAR END:			1031

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-00898
		FILM NUMBER:		06869153

	BUSINESS ADDRESS:	
		STREET 1:		ONE CORPORATE CENTER
		CITY:			RYE
		STATE:			NY
		ZIP:			10580-1434
		BUSINESS PHONE:		9149215128

	MAIL ADDRESS:	
		STREET 1:		ONE CORPORATE CENTER
		CITY:			RYE
		STATE:			NY
		ZIP:			10580

	FORMER NAME:	
		FORMER CONFORMED NAME:	GABELLI ASSET MANAGEMENT INC ET AL
		DATE OF NAME CHANGE:	20020828

	FORMER NAME:	
		FORMER CONFORMED NAME:	GABELLI FUNDS INC ET AL
		DATE OF NAME CHANGE:	19940714
</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>2006-05-25</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000006176</issuerCik>
        <issuerName>AMPCO PITTSBURGH CORP</issuerName>
        <issuerTradingSymbol>AP</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000807249</rptOwnerCik>
            <rptOwnerName>GAMCO INVESTORS, INC. ET AL</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>ONE CORPORATE CENTER</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>RYE</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10580</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001185533</rptOwnerCik>
            <rptOwnerName>GABELLI MARIO J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O GAMCO INVESTORS, INC</rptOwnerStreet1>
            <rptOwnerStreet2>ONE CORPORATE CENTER</rptOwnerStreet2>
            <rptOwnerCity>RYE</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10580</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001238894</rptOwnerCik>
            <rptOwnerName>GGCP, INC.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>140 GREENWICH AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>GREENWICH</rptOwnerCity>
            <rptOwnerState>CT</rptOwnerState>
            <rptOwnerZipCode>06830</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2006-05-25</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1100</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>34.5055</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>28400</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By: Investment Partnership</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>45000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The Reporting Persons have less than a 100% interest in this entity. The amount of securities reported as beneficially owned reflects the total amount of securities held by this entity which is greater than the Reporting Persons indirect pecuniary interests. The Reporting Persons hereby disclaim ownership of these securities in excess of their pecuniary interests.</footnote>
        <footnote id="F2">These securities are owned by GGCP, Inc. Mr. Mario J. Gabelli has less than a 100% interest in GGCP, Inc. and hereby disclaims beneficial ownership of these securities in excess of his pecuniary interest. GAMCO Investors, Inc. has no interest in GGCP, Inc.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ James E. McKee                    Attorney-in-Fact for MARIO J. GABELLI and GGCP, INC. and Secretary for GAMCO INVESTORS, INC.</signatureName>
        <signatureDate>2006-05-26</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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