-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 Jz62oCwiO/2tIUyNDUAYCHGSANMKYkQIBlDCNeZPlB3Klet+RoWXS8HIiJ6ptvTt
 684lPqh1hBs3gB2wJw4n6Q==

<SEC-DOCUMENT>0001031323-10-000019.txt : 20100910
<SEC-HEADER>0001031323-10-000019.hdr.sgml : 20100910
<ACCEPTANCE-DATETIME>20100910145659
ACCESSION NUMBER:		0001031323-10-000019
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100909
FILED AS OF DATE:		20100910
DATE AS OF CHANGE:		20100910

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Ruder Sven
		CENTRAL INDEX KEY:			0001437975

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-14097
		FILM NUMBER:		101066396

	MAIL ADDRESS:	
		STREET 1:		SAUER-DANFOSS GMBH & CO. OHG
		STREET 2:		KROKAMP 35
		CITY:			NEUMUNSTER
		STATE:			2M
		ZIP:			24539

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SAUER DANFOSS INC
		CENTRAL INDEX KEY:			0000865754
		STANDARD INDUSTRIAL CLASSIFICATION:	MISC INDUSTRIAL & COMMERCIAL MACHINERY & EQUIPMENT [3590]
		IRS NUMBER:				363482074
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		2800 EAST 13TH STREET
		CITY:			AMES
		STATE:			IA
		ZIP:			50010
		BUSINESS PHONE:		5152396000

	MAIL ADDRESS:	
		STREET 1:		2800 EAST 13TH STREET
		CITY:			AMES
		STATE:			IA
		ZIP:			50010

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	SAUER INC
		DATE OF NAME CHANGE:	19940929
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-09-09</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000865754</issuerCik>
        <issuerName>SAUER DANFOSS INC</issuerName>
        <issuerTradingSymbol>SHS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001437975</rptOwnerCik>
            <rptOwnerName>Ruder Sven</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>SAUER-DANFOSS GMBH &amp; CO. OHG</rptOwnerStreet1>
            <rptOwnerStreet2>KROKAMP 35</rptOwnerStreet2>
            <rptOwnerCity>NEUMUNSTER</rptOwnerCity>
            <rptOwnerState>2M</rptOwnerState>
            <rptOwnerZipCode>24539</rptOwnerZipCode>
            <rptOwnerStateDescription>GERMANY</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President and CEO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-09-09</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>5000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>18.5</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>11500</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <ownerSignature>
        <signatureName>Sven Ruder</signatureName>
        <signatureDate>2010-09-10</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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