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  <xs:element id="knx_IncreaseDecreaseinAccruedLiabilitiesandOtherLiabilities" abstract="false" name="IncreaseDecreaseinAccruedLiabilitiesandOtherLiabilities" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="knx_FinancingProvidedToIndependentContractorsForEquipmentSoldMember" abstract="true" name="FinancingProvidedToIndependentContractorsForEquipmentSoldMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_TransfersfrompropertyandequipmenttoassetsheldforsaleMember" abstract="true" name="TransfersfrompropertyandequipmenttoassetsheldforsaleMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_PropertyAndEquipmentObtainedInExchangeForFinanceLeaseLiabilitiesFromOperatingLeaseLiabilitiesMember" abstract="true" name="PropertyAndEquipmentObtainedInExchangeForFinanceLeaseLiabilitiesFromOperatingLeaseLiabilitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_RightOfUseAssetForfeitedObtainedInExchangeForOperatingLeaseLiability" abstract="false" name="RightOfUseAssetForfeitedObtainedInExchangeForOperatingLeaseLiability" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="knx_ConvertibleSeniorNotesDisclosureTextBlockTextBlock" abstract="false" name="ConvertibleSeniorNotesDisclosureTextBlockTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="knx_ScheduleofDebtBalancesbyInstrumentTableTextBlock" abstract="false" name="ScheduleofDebtBalancesbyInstrumentTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="knx_NumberofTractorsInFleet" abstract="false" name="NumberofTractorsInFleet" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="knx_NumberOfTractorsDrivenByCompanyDrivers" abstract="false" name="NumberOfTractorsDrivenByCompanyDrivers" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="knx_NumberOfOwnerOperatorTractors" abstract="false" name="NumberOfOwnerOperatorTractors" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="knx_NumberOfTrailersInFleet" abstract="false" name="NumberOfTrailersInFleet" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="knx_NumberOfLTLTractors" abstract="false" name="NumberOfLTLTractors" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="knx_NumberOfLTLTrailers" abstract="false" name="NumberOfLTLTrailers" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="knx_NumberOfIntermodalTractors" abstract="false" name="NumberOfIntermodalTractors" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="knx_NumberOfIntermodalContainers" abstract="false" name="NumberOfIntermodalContainers" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="knx_AccountingStandardsUpdate202602Member" abstract="true" name="AccountingStandardsUpdate202602Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_AccountingStandardsUpdate202601Member" abstract="true" name="AccountingStandardsUpdate202601Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_NewAccountingPronouncementAdoptionMethodandDate" abstract="false" name="NewAccountingPronouncementAdoptionMethodandDate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="knx_NewAccountingPronouncementFinancialStatementImpact" abstract="false" name="NewAccountingPronouncementFinancialStatementImpact" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="knx_A2025RPAMember" abstract="true" name="A2025RPAMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_MaximumFacilityCapacity" abstract="false" name="MaximumFacilityCapacity" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="knx_UnsoldReceivables" abstract="false" name="UnsoldReceivables" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="knx_SecuritizationEffectiveDate" abstract="false" name="SecuritizationEffectiveDate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:dateItemType"/>
  <xs:element id="knx_SecuritizationMaturityDate" abstract="false" name="SecuritizationMaturityDate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:dateItemType"/>
  <xs:element id="knx_UnusedCommitmentFeeRate" abstract="false" name="UnusedCommitmentFeeRate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="knx_ProgramFeesRate" abstract="false" name="ProgramFeesRate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="knx_FacilityCapacity" abstract="false" name="FacilityCapacity" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="knx_RPAAvailability" abstract="false" name="RPAAvailability" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="knx_A2025TermLoanA1Member" abstract="true" name="A2025TermLoanA1Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_A2025TermLoanA2Member" abstract="true" name="A2025TermLoanA2Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_U.S.XpressRevenueEquipmentInstallmentNotesMember" abstract="true" name="U.S.XpressRevenueEquipmentInstallmentNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_A2021PrudentialNotesMember" abstract="true" name="A2021PrudentialNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_OtherDebtMember" abstract="true" name="OtherDebtMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_A2025RevolverMember" abstract="true" name="A2025RevolverMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_CapitalAdditionPurchaseCommitmentsTotalRevenueEquipmentMember" abstract="true" name="CapitalAdditionPurchaseCommitmentsTotalRevenueEquipmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_CapitalAdditionPurchaseCommitmentsofTractorsMember" abstract="true" name="CapitalAdditionPurchaseCommitmentsofTractorsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_CapitalAdditionPurchaseCommitmentsNonrevenueequipmentMember" abstract="true" name="CapitalAdditionPurchaseCommitmentsNonrevenueequipmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_February142024AgreementMember" abstract="true" name="February142024AgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_December282024AgreementMember" abstract="true" name="December282024AgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_KnightSwiftShareRepurchasePlanApril192022Member" abstract="true" name="KnightSwiftShareRepurchasePlanApril192022Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_USXpressMember" abstract="true" name="USXpressMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_ClassAMember" abstract="true" name="ClassAMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_MeasurementInputVolatilityOperatingIncomeMember" abstract="true" name="MeasurementInputVolatilityOperatingIncomeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_MeasurementInputVolatilityNetIncomeMember" abstract="true" name="MeasurementInputVolatilityNetIncomeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_FacilityandEquipmentLeasesMember" abstract="true" name="FacilityandEquipmentLeasesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_OtherServicesMember" abstract="true" name="OtherServicesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_TruckingMember" abstract="true" name="TruckingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_LTLMember" abstract="true" name="LTLMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_LogisticsMember" abstract="true" name="LogisticsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_IntermodalMember" abstract="true" name="IntermodalMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="knx_OtherSegmentItems" abstract="false" name="OtherSegmentItems" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="knx_OperatingRatio" abstract="false" name="OperatingRatio" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="knx_PercentagesOfForeignOperationsConsolidatedRevenue" abstract="false" name="PercentagesOfForeignOperationsConsolidatedRevenue" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="knx_Longlivedassetsofforeignoperations" abstract="false" name="Longlivedassetsofforeignoperations" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
</xs:schema>
