-----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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 JAxnWgu2tFiYr022zsMslQ==

<SEC-DOCUMENT>0001140361-06-003560.txt : 20060308
<SEC-HEADER>0001140361-06-003560.hdr.sgml : 20060308
<ACCEPTANCE-DATETIME>20060308163947
ACCESSION NUMBER:		0001140361-06-003560
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060306
FILED AS OF DATE:		20060308
DATE AS OF CHANGE:		20060308

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:			MOYES JERRY & VICKIE FAMILY TRUST
		CENTRAL INDEX KEY:			0001092565

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-18605
		FILM NUMBER:		06673547

	BUSINESS ADDRESS:	
		STREET 1:		C/O SWIFT TRANSPORTATION CO INC
		STREET 2:		P.O. BOX 29243
		CITY:			PHOENIX
		STATE:			AZ
		ZIP:			85043
		BUSINESS PHONE:		6022699700

	MAIL ADDRESS:	
		STREET 1:		C/O SWIFT TRANSPORTATION CO INC
		STREET 2:		P.O. BOX 29243
		CITY:			PHOENIX
		STATE:			AZ
		ZIP:			85038
</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>2006-03-06</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001092565</rptOwnerCik>
            <rptOwnerName>MOYES JERRY &amp; VICKIE FAMILY TRUST</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O SWIFT AVIATION GROUP, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>2710 E. OLD TOWER ROAD</rptOwnerStreet2>
            <rptOwnerCity>PHOENIX</rptOwnerCity>
            <rptOwnerState>AZ</rptOwnerState>
            <rptOwnerZipCode>85034</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Call option (obligation to sell)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>27.5677</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2006-03-06</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>1</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2007-03-06</value>
            </exerciseDate>
            <expirationDate>
                <value>2007-03-06</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>650000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Put option (right to sell)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>21.5747</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2006-03-06</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>1</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2007-03-06</value>
            </exerciseDate>
            <expirationDate>
                <value>2007-03-06</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>650000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">On 03/06/06, the reporting person entered into an equity collar agreement pursuant to which it wrote a covered call option and purchased a put option.  Only one option can be in-the-money on the expiration date, at which time the in-the-money option will be settled for cash, and the other option will expire.  If, on the expiration date, the &quot;Final Price&quot; (a market-based price determined under the terms of the collar agreement) is greater than the Cap Price, the reporting person will deliver cash equal to the difference between the Final Price and the Cap Price multiplied by the number of underlying shares.  If, on the expiration date, the Final Price is less than the Floor Price, the reporting person will receive cash equal to the difference between the Floor Price and the Final Price multiplied by the number of underlying shares.  If neither option is in-the-money on the expiration date, both will expire.  The Floor Price is $21.5747.  The Cap Price is $27.5677.</footnote
>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Jerry Moyes as Trustee of the Jerry &amp; Vickie Moyes Family Trust dated 12/11/87</signatureName>
        <signatureDate>2006-03-08</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----