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  <xsd:import namespace="https://xbrl.org/2023/calculation-1.1" schemaLocation="https://www.xbrl.org/2023/calculation-1.1.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/ecd/2026" schemaLocation="https://xbrl.sec.gov/ecd/2026/ecd-2026.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/dei/2026" schemaLocation="https://xbrl.sec.gov/dei/2026/dei-2026.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
  <xsd:import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2009/role/negated" schemaLocation="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2009/role/net" schemaLocation="http://www.xbrl.org/lrr/role/net-2009-12-16.xsd" />
  <xsd:import namespace="http://www.xbrl.org/dtr/type/2024-01-31" schemaLocation="https://www.xbrl.org/dtr/type/2024-01-31/types.xsd" />
  <xsd:import namespace="http://fasb.org/us-roles/2026" schemaLocation="https://xbrl.fasb.org/us-gaap/2026/elts/us-roles-2026.xsd" />
  <xsd:import namespace="http://fasb.org/us-gaap/2026" schemaLocation="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd" />
  <xsd:import namespace="http://fasb.org/srt/2026" schemaLocation="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/ecd-sub/2026" schemaLocation="https://xbrl.sec.gov/ecd/2026/ecd-sub-2026.xsd" />
  <xsd:element name="InventoryChassisNetOfReserves" id="mlr_InventoryChassisNetOfReserves" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item" />
  <xsd:element id="mlr_OperatingAndNonoperatingIncomeExpense" name="OperatingAndNonoperatingIncomeExpense" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="mlr_BonifaceEngineeringLtd.Member" name="BonifaceEngineeringLtd.Member" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="mlr_JigeInternationalS.a.Member" name="JigeInternationalS.a.Member" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="mlr_NumberOfCustomer" name="NumberOfCustomer" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="mlr_StockIncentivePlan2016Member" name="StockIncentivePlan2016Member" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="mlr_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour" name="LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element name="ProceedsFromSaleOfPropertyPlantAndEquipment1" id="mlr_ProceedsFromSaleOfPropertyPlantAndEquipment1" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ScheduleOfAdditionalInformationRelatedToRestrictedShareUnitActivityTableTextBlock" id="mlr_ScheduleOfAdditionalInformationRelatedToRestrictedShareUnitActivityTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LeaseDisclosureTextBlock" id="mlr_LeaseDisclosureTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ScheduleOfWeightedAverageLeaseTermAndDiscountRateOfOperatingAndFinanceLeaseTableTextBlock" id="mlr_ScheduleOfWeightedAverageLeaseTermAndDiscountRateOfOperatingAndFinanceLeaseTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="FirstHorizonBankMember" id="mlr_FirstHorizonBankMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="WilliamGMillerIIMember" id="mlr_WilliamGMillerIIMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="JeffreyIBadgleyMember" id="mlr_JeffreyIBadgleyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="Rule10b51ArrangementModifiedFlag" id="mlr_Rule10b51ArrangementModifiedFlag" type="xbrli:booleanItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="NonRule10b51ArrangementModifiedFlag" id="mlr_NonRule10b51ArrangementModifiedFlag" type="xbrli:booleanItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="SignificantAccountingPoliciesPolicyTextBlock" id="mlr_SignificantAccountingPoliciesPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="RevenueIncreaseDecreaseInPercentage" id="mlr_RevenueIncreaseDecreaseInPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="IssuanceOfCommonStockNetOfShares" id="mlr_IssuanceOfCommonStockNetOfShares" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ScheduleOfSupplementalCashFlowInformationOfFinanceAndOperatingLeaseTableTextBlock" id="mlr_ScheduleOfSupplementalCashFlowInformationOfFinanceAndOperatingLeaseTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="NonEmployeeDirectorStockPlan2023Member" id="mlr_NonEmployeeDirectorStockPlan2023Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SingleReportingSegmentMember" id="mlr_SingleReportingSegmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="StockIncentivePlan2025Member" id="mlr_StockIncentivePlan2025Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="FacilityExpansionInFranceMember" id="mlr_FacilityExpansionInFranceMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="OmarsS.p.aMember" id="mlr_OmarsS.p.aMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CustomerRelationsMember" id="mlr_CustomerRelationsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RetirementPlanMatchPercentageAxis" id="mlr_RetirementPlanMatchPercentageAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RetirementPlanMatchPercentageDomain" id="mlr_RetirementPlanMatchPercentageDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RepurchasesOfInventory" id="mlr_RepurchasesOfInventory" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ContingencyEstimateOfCostOfProject" id="mlr_ContingencyEstimateOfCostOfProject" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="RestrictedStockRightToReceiveShares" id="mlr_RestrictedStockRightToReceiveShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="DaysVestedSharesAreIssuedWithin" id="mlr_DaysVestedSharesAreIssuedWithin" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LeasesOperating1Abstract" id="mlr_LeasesOperating1Abstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="O2026Q3DividendsMember" id="mlr_O2026Q3DividendsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
</xsd:schema>
