<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2016-04-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001327318</issuerCik>
        <issuerName>TrueCar, Inc.</issuerName>
        <issuerTradingSymbol>TRUE</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001021249</rptOwnerCik>
            <rptOwnerName>UNITED SERVICES AUTOMOBILE ASSOCIATION</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>9800 FREDERICKSBURG RD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SAN ANTONIO</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>78288</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001607293</rptOwnerCik>
            <rptOwnerName>USAA Property Holdings, Inc.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>9800 FREDERICKSBURG ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SAN ANTONIO</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>78288</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>2016-04-01</value>
                <footnoteId id="F1"/>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>117000</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>5.336</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10915346</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2016-04-04</value>
                <footnoteId id="F1"/>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>73000</value>
                    <footnoteId id="F4"/>
                    <footnoteId id="F5"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>5.2972</value>
                    <footnoteId id="F4"/>
                    <footnoteId id="F5"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10842346</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1633347</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>USAA Property Holdings, Inc.</value>
                    <footnoteId id="F6"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The transactions reported on this form were executed pursuant to a 10b5-1 plan adopted as of August 26, 2015.</footnote>
        <footnote id="F2">Execution Breakdown of Price/Sold Shares: (continuation will be included in footnote #3)

PRICE     SOLD SHARES

$5.21    $400
$5.215   $674
$5.22    $300
$5.225   $300
$5.23    $700
$5.24    $2,600
$5.25    $1,912
$5.26    $600
$5.265   $1,400
$5.27    $1,478
$5.28    $5,228
$5.285   $1,800
$5.29    $7,456
$5.30    $11,077
$5.305   $467
$5.31    $14,428
$5.315   $900
$5.32    $2,728
$5.325   $700
$5.33    $7,523</footnote>
        <footnote id="F3">Execution Breakdown of Price/Sold Shares: (continuation from footnote #2)

PRICE     SOLD SHARES

$5.335   $1,421
$5.34    $6,191
$5.345   $700
$5.35    $7,515
$5.355   $2,208
$5.36    $4,005
$5.365   $2,087
$5.37    $2,700
$5.375   $621
$5.38    $3,500
$5.385   $600
$5.39    $2,277
$5.395   $800
$5.40    $3,205
$5.405   $200
$5.41    $4,430
$5.415   $200
$5.42    $3,470
$5.425 	 $500
$5.43    $2,160
$5.435   $200
$5.44    $1,639
$5.45    $1,500
$5.455 	 $300
$5.46    $800
$5.48    $1,100</footnote>
        <footnote id="F4">Execution Breakdown of Price/Sold Shares: (continuation will be included in footnote #5)

PRICE     SOLD SHARES

$5.18    $600
$5.19    $1,100
$5.20    $900
$5.21    $2,303
$5.215   $200
$5.22    $1,557
$5.23    $4,701
$5.235   $500
$5.24    $6,300
$5.245   $300
$5.25    $6,204
$5.255   $500
$5.26    $3,400
$5.27    $2,400
$5.275   $300
$5.28    $500
$5.29    $2,400
$5.30    $4,091
$5.302   $200
$5.305   $1,322
$5.31    $5,378
$5.315   $268
$5.32    $3,800</footnote>
        <footnote id="F5">Execution Breakdown of Price/Sold Shares: (continuation from footnote #4)

PRICE     SOLD SHARES

$5.325   $400
$5.33    $3,435
$5.335   $888
$5.34    $3,800
$5.345   $400
$5.35    $2,056
$5.355   $200
$5.36    $600
$5.365   $1,000
$5.37    $1,300
$5.375   $400
$5.38    $1,300
$5.385   $1,032
$5.39    $379
$5.395   $200
$5.40    $400
$5.405   $500
$5.41    $2,426
$5.415   $600
$5.42    $1,800
$5.425   $100
$5.43    $405
$5.44    $155</footnote>
        <footnote id="F6">USAA Property Holdings, Inc. is a wholly owned subsidiary of United Services Automobile Association.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Douglas I. Ward, Vice President and Chief Investment Officer</signatureName>
        <signatureDate>2016-04-05</signatureDate>
    </ownerSignature>
</ownershipDocument>
