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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>0000075362-07-000003.txt : 20070104
<SEC-HEADER>0000075362-07-000003.hdr.sgml : 20070104
<ACCEPTANCE-DATETIME>20070104121735
ACCESSION NUMBER:		0000075362-07-000003
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20070103
FILED AS OF DATE:		20070104
DATE AS OF CHANGE:		20070104

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			CARNWATH ALISON J
		CENTRAL INDEX KEY:			0001339413

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-14817
		FILM NUMBER:		07507965

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		425 468 7431

	MAIL ADDRESS:	
		STREET 1:		777 106TH AVENUE NE
		CITY:			BELLEVUE
		STATE:			WA
		ZIP:			98004

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			PACCAR INC
		CENTRAL INDEX KEY:			0000075362
		STANDARD INDUSTRIAL CLASSIFICATION:	MOTOR VEHICLES & PASSENGER CAR BODIES [3711]
		IRS NUMBER:				910351110
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		PACCAR BUILDING
		STREET 2:		777 106TH AVENUE NE
		CITY:			BELLEVUE
		STATE:			WA
		ZIP:			98004
		BUSINESS PHONE:		425 468 7383

	MAIL ADDRESS:	
		STREET 1:		PACCAR BUILDING
		STREET 2:		777 106TH AVENUE NE
		CITY:			BELLEVUE
		STATE:			WA
		ZIP:			98004

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	PACIFIC CAR & FOUNDRY CO
		DATE OF NAME CHANGE:	19720707
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2007-01-03</periodOfReport>

    <issuer>
        <issuerCik>0000075362</issuerCik>
        <issuerName>PACCAR INC</issuerName>
        <issuerTradingSymbol>PCAR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001339413</rptOwnerCik>
            <rptOwnerName>CARNWATH ALISON J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>777 106TH AVENUE NE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BELLEVUE</rptOwnerCity>
            <rptOwnerState>WA</rptOwnerState>
            <rptOwnerZipCode>98004</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>COMMON STOCK</value>
            </securityTitle>
            <transactionDate>
                <value>2007-01-03</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1387</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>64.91</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3637</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Restricted stock awarded under PACCAR Restricted Stock and Deferred Compensation Plan for Non-Employee Directors.</footnote>
        <footnote id="F2">On July 11, 2006 PACCAR declared a stock dividend of one additional share of common stock for every two shares of common stock payable August 10, 2006 to all holders of record of common stock on July  27, 2006.  As a result of the stock dividend the reporting person received 750 additional shares of PACCAR common stock on August 10, 2006.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Alison Carnwath by Janice M. D'Amato POA</signatureName>
        <signatureDate>2007-01-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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