-----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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 99wbaQ/m16wkmeG0QT+eLA==

<SEC-DOCUMENT>0000863557-06-000005.txt : 20060404
<SEC-HEADER>0000863557-06-000005.hdr.sgml : 20060404
<ACCEPTANCE-DATETIME>20060404160434
ACCESSION NUMBER:		0000863557-06-000005
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060403
FILED AS OF DATE:		20060404
DATE AS OF CHANGE:		20060404

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SWIFT TRANSPORTATION CO INC
		CENTRAL INDEX KEY:			0000863557
		STANDARD INDUSTRIAL CLASSIFICATION:	TRUCKING (NO LOCAL) [4213]
		IRS NUMBER:				860666860
		STATE OF INCORPORATION:			NV
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		2200 SOUTH 75TH AVENUE
		CITY:			PHOENIX
		STATE:			AZ
		ZIP:			85043
		BUSINESS PHONE:		6022699700

	MAIL ADDRESS:	
		STREET 1:		2200 SOUTH 75TH AVENUE
		CITY:			PHOENIX
		STATE:			AZ
		ZIP:			85043

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MARTIN MARK A
		CENTRAL INDEX KEY:			0001281971

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-18605
		FILM NUMBER:		06738139

	BUSINESS ADDRESS:	
		STREET 1:		2200 S 75TH AVE
		CITY:			PHOENIX
		STATE:			AZ
		ZIP:			85043
		BUSINESS PHONE:		6022699700
</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>2006-04-03</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000863557</issuerCik>
        <issuerName>SWIFT TRANSPORTATION CO INC</issuerName>
        <issuerTradingSymbol>swft</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001281971</rptOwnerCik>
            <rptOwnerName>MARTIN MARK A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O SWIFT TRANSPORTATION</rptOwnerStreet1>
            <rptOwnerStreet2>P.O. BOX 29243</rptOwnerStreet2>
            <rptOwnerCity>PHOENIX</rptOwnerCity>
            <rptOwnerState>AZ</rptOwnerState>
            <rptOwnerZipCode>85038</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Executive Vice President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Non-Qualified Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>22.65</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2006-04-03</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>22500</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>22.65</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2007-04-03</value>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2013-04-03</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>22500</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>22500</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Stock Option award, which is the right to buy 22,500 shares of common stock at an exercise price of $22.65 per share, which vest at 20% a year beginning on 04/03/07 and expiring on 04/03/13.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Mark A Martin</signatureName>
        <signatureDate>2006-04-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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