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  <xs:element id="gbdc4_DividendsAndDistributionsTextBlock" abstract="false" name="DividendsAndDistributionsTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="gbdc4_ScheduleOfDebtSecuritizationTableTextBlock" abstract="false" name="ScheduleOfDebtSecuritizationTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="gbdc4_ScheduleOfReclassificationTaxableIncomeTableTextBlock" abstract="false" name="ScheduleOfReclassificationTaxableIncomeTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="gbdc4_ReconciliationOfTaxableIncomeIncreaseDecreaseInNetAssetsFromOperationTableTextBlock" abstract="false" name="ReconciliationOfTaxableIncomeIncreaseDecreaseInNetAssetsFromOperationTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="gbdc4_ScheduleOfTaxCharacterOfDistributionsPaidTableTextBlock" abstract="false" name="ScheduleOfTaxCharacterOfDistributionsPaidTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="gbdc4_ScheduleOfAccumulatedEarningsDeficitBookBasisIncomeTaxTableTextBlock" abstract="false" name="ScheduleOfAccumulatedEarningsDeficitBookBasisIncomeTaxTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="gbdc4_ScheduleOfSummarizedDividendReinvestmentPlanInformationTableTextBlock" abstract="false" name="ScheduleOfSummarizedDividendReinvestmentPlanInformationTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="gbdc4_InterestIncomeOperatingAccretionOfDiscounts" abstract="false" name="InterestIncomeOperatingAccretionOfDiscounts" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gbdc4_InvestmentCompanyPremiumPrepaymentFees" abstract="false" name="InvestmentCompanyPremiumPrepaymentFees" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gbdc4_InterestAndFeeIncomeOperatingPaidInCash" abstract="false" name="InterestAndFeeIncomeOperatingPaidInCash" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gbdc4_DividendIncomeOperatingNonCash" abstract="false" name="DividendIncomeOperatingNonCash" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gbdc4_FairValueOptionPreferredEquitySecuritiesAggregateAmountInNonaccrualStatus" abstract="false" name="FairValueOptionPreferredEquitySecuritiesAggregateAmountInNonaccrualStatus" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gbdc4_DeferredOfferingCostAmortizationDuration" abstract="false" name="DeferredOfferingCostAmortizationDuration" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="gbdc4_IssuanceOfStockSubscriptionAgreementsMinimumNoticePeriod" abstract="false" name="IssuanceOfStockSubscriptionAgreementsMinimumNoticePeriod" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="gbdc4_InvestmentCompanyContributedCapitalToSubscribedCapitalRatio" abstract="false" name="InvestmentCompanyContributedCapitalToSubscribedCapitalRatio" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="gbdc4_InvestmentCompanyUncalledCapitalCommitments" abstract="false" name="InvestmentCompanyUncalledCapitalCommitments" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gbdc4_InvestmentCompanySubscribedCapital" abstract="false" name="InvestmentCompanySubscribedCapital" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gbdc4_InvestmentCompanyContributedCapital" abstract="false" name="InvestmentCompanyContributedCapital" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gbdc4_InvestmentAdvisoryAgreementMember" abstract="true" name="InvestmentAdvisoryAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_InvestmentManagementAgreementIncentiveRateQuarterlyHurdleRateMember" abstract="true" name="InvestmentManagementAgreementIncentiveRateQuarterlyHurdleRateMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_InvestmentManagementAgreementQuarterlyIncentiveRateCriteriaNotMetMember" abstract="true" name="InvestmentManagementAgreementQuarterlyIncentiveRateCriteriaNotMetMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_InvestmentManagementAgreementIncentiveRatePreIncentiveFeeNetInvestmentIncomeBelowCatchUpMember" abstract="true" name="InvestmentManagementAgreementIncentiveRatePreIncentiveFeeNetInvestmentIncomeBelowCatchUpMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_InvestmentAdvisoryAgreementCumulativePreIncentiveFeeNetInvestmentIncomeMember" abstract="true" name="InvestmentAdvisoryAgreementCumulativePreIncentiveFeeNetInvestmentIncomeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_InvestmentAdvisoryAgreementCapitalGainIncentiveFeeBaseMember" abstract="true" name="InvestmentAdvisoryAgreementCapitalGainIncentiveFeeBaseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_InvestmentAdvisoryAgreementSubordinatedLiquidationIncentiveFeeBaseMember" abstract="true" name="InvestmentAdvisoryAgreementSubordinatedLiquidationIncentiveFeeBaseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_AdministrationAgreementMember" abstract="true" name="AdministrationAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_InvestmentAdviserMember" abstract="true" name="InvestmentAdviserMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_ExpensesPaidMember" abstract="true" name="ExpensesPaidMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_ConversionToMarylandCorporationAcquisitionOfStockMember" abstract="true" name="ConversionToMarylandCorporationAcquisitionOfStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_IncentiveFeeScenarioAxis" abstract="true" name="IncentiveFeeScenarioAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="gbdc4_IncentiveFeeScenarioDomain" abstract="true" name="IncentiveFeeScenarioDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_PeriodsEndingOnOrPriorToTheDateOfTheClosingOfTheLiquidityEventMember" abstract="true" name="PeriodsEndingOnOrPriorToTheDateOfTheClosingOfTheLiquidityEventMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_PeriodsEndingAfterTheDateOfTheClosingOfTheLiquidityEventMember" abstract="true" name="PeriodsEndingAfterTheDateOfTheClosingOfTheLiquidityEventMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_GGPHoldingsLPMember" abstract="true" name="GGPHoldingsLPMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_GGPClassBPLLCMember" abstract="true" name="GGPClassBPLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_ManagementAndServiceFeesNumberOfComponents" abstract="false" name="ManagementAndServiceFeesNumberOfComponents" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="gbdc4_ManagementAndServiceFeesCashEquivalentsMaturityPeriod" abstract="false" name="ManagementAndServiceFeesCashEquivalentsMaturityPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="gbdc4_InvestmentCompanyLiquidityEventManagementAndServiceFeesBaseRateWaiverThresholdPercentageOfFairValueOfAverageAdjustedGrossAssets" abstract="false" name="InvestmentCompanyLiquidityEventManagementAndServiceFeesBaseRateWaiverThresholdPercentageOfFairValueOfAverageAdjustedGrossAssets" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gbdc4_InvestmentCompanyNumberOfIncentiveFeeComponents" abstract="false" name="InvestmentCompanyNumberOfIncentiveFeeComponents" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="gbdc4_InvestmentCompanyLiquidityEventManagementAndServiceFeesIncentiveRateWaiverThresholdPercentageOfCapitalGainIncentiveFeeBase" abstract="false" name="InvestmentCompanyLiquidityEventManagementAndServiceFeesIncentiveRateWaiverThresholdPercentageOfCapitalGainIncentiveFeeBase" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gbdc4_PaymentForCapitalGainsIncentiveFee" abstract="false" name="PaymentForCapitalGainsIncentiveFee" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gbdc4_ManagementAndServiceFeesIncentiveRateCapPercentageOfCumulativePreIncentiveFeeNetIncome" abstract="false" name="ManagementAndServiceFeesIncentiveRateCapPercentageOfCumulativePreIncentiveFeeNetIncome" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gbdc4_InvestmentCompanyReimbursableExcessExpenseAmountPaid" abstract="false" name="InvestmentCompanyReimbursableExcessExpenseAmountPaid" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gbdc4_RelatedPartyTransactionShareTransferred" abstract="false" name="RelatedPartyTransactionShareTransferred" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="gbdc4_CommonStockSharesIssuedDividendReinvestmentPlan" abstract="false" name="CommonStockSharesIssuedDividendReinvestmentPlan" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="gbdc4_DebtSecuritiesSeniorSecuredLoanMember" abstract="true" name="DebtSecuritiesSeniorSecuredLoanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_DebtSecuritiesOneStopLoansMember" abstract="true" name="DebtSecuritiesOneStopLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_DebtSecuritiesSecondLienMember" abstract="true" name="DebtSecuritiesSecondLienMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_USMidAtlanticMember" abstract="true" name="USMidAtlanticMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_InvestmentsAtAmortizedCostMember" abstract="true" name="InvestmentsAtAmortizedCostMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_IndustryConcentrationRiskMember" abstract="true" name="IndustryConcentrationRiskMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_SMBCCapitalMarketsInc.Member" abstract="true" name="SMBCCapitalMarketsInc.Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_DerivativeAverageNotionalAmount" abstract="false" name="DerivativeAverageNotionalAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gbdc4_DebtAndEquitySecuritiesUnrealizedGainLossMember" abstract="true" name="DebtAndEquitySecuritiesUnrealizedGainLossMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_UnrealizedGainLossForeignCurrencyTransactionBeforeTaxMember" abstract="true" name="UnrealizedGainLossForeignCurrencyTransactionBeforeTaxMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_DebtAndEquitySecuritiesRealizedGainLossMember" abstract="true" name="DebtAndEquitySecuritiesRealizedGainLossMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_RealizedGainLossForeignCurrencyTransactionBeforeTaxMember" abstract="true" name="RealizedGainLossForeignCurrencyTransactionBeforeTaxMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_GrossInvestmentIncomeOperatingMember" abstract="true" name="GrossInvestmentIncomeOperatingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssuancesSettlementsOfUndrawnPortionOfRevolvingLoans" abstract="false" name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssuancesSettlementsOfUndrawnPortionOfRevolvingLoans" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gbdc4_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPaidInKindInterest" abstract="false" name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPaidInKindInterest" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gbdc4_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetProceedsFromNonCashDividends" abstract="false" name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetProceedsFromNonCashDividends" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gbdc4_DebtSecuritiesSubordinatedDebtAndSecondLienLoanMember" abstract="true" name="DebtSecuritiesSubordinatedDebtAndSecondLienLoanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_MeasurementInputMarketInterestRateMember" abstract="true" name="MeasurementInputMarketInterestRateMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_ValuationYieldAnalysisMember" abstract="true" name="ValuationYieldAnalysisMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_ValuationTechniqueBrokerDealerBidsOrQuotesMember" abstract="true" name="ValuationTechniqueBrokerDealerBidsOrQuotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_ValuationMarketComparableCompanyMember" abstract="true" name="ValuationMarketComparableCompanyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_DebtSecuritization2025Member" abstract="true" name="DebtSecuritization2025Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_PNCFacilityMember" abstract="true" name="PNCFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_DBCreditFacilityMember" abstract="true" name="DBCreditFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_BNPCreditFacilityMember" abstract="true" name="BNPCreditFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_AdviserRevolverMember" abstract="true" name="AdviserRevolverMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_DebtSecuritizationTypeAxis" abstract="true" name="DebtSecuritizationTypeAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="gbdc4_DebtSecuritizationTypeDomain" abstract="true" name="DebtSecuritizationTypeDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_ClassA1SeniorSecuredFloatingRateNotesDue2037Member" abstract="true" name="ClassA1SeniorSecuredFloatingRateNotesDue2037Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_ClassA2SeniorSecuredFloatingRateNotesDue2037Member" abstract="true" name="ClassA2SeniorSecuredFloatingRateNotesDue2037Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_ClassBSeniorSecuredFloatingRateNotesDue2037Member" abstract="true" name="ClassBSeniorSecuredFloatingRateNotesDue2037Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_ClassCSeniorSecuredFloatingRateNotesDue2037Member" abstract="true" name="ClassCSeniorSecuredFloatingRateNotesDue2037Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_CanadianOvernightRepoRateAverageMember" abstract="true" name="CanadianOvernightRepoRateAverageMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_SterlingOvernightIndexAverageMember" abstract="true" name="SterlingOvernightIndexAverageMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_ShortTermApplicableFederalRateMember" abstract="true" name="ShortTermApplicableFederalRateMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_InvestmentCompanySeniorSecurityIndebtednessAssetCoverageRatioMinimumThreshold" abstract="false" name="InvestmentCompanySeniorSecurityIndebtednessAssetCoverageRatioMinimumThreshold" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="gbdc4_NumberOfInvestmentPortfolioCompanies" abstract="false" name="NumberOfInvestmentPortfolioCompanies" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="gbdc4_DebtInstrumentCreditSpreadAdjustment" abstract="false" name="DebtInstrumentCreditSpreadAdjustment" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gbdc4_LineOfCreditFacilityPrepaymentFeePercentageYearOne" abstract="false" name="LineOfCreditFacilityPrepaymentFeePercentageYearOne" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gbdc4_LineOfCreditFacilityPrepaymentFeePercentageYearTwo" abstract="false" name="LineOfCreditFacilityPrepaymentFeePercentageYearTwo" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gbdc4_DebtAnnualizedWeightedAverageInterestRate" abstract="false" name="DebtAnnualizedWeightedAverageInterestRate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gbdc4_OtherShortTermBorrowingsMember" abstract="true" name="OtherShortTermBorrowingsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_FacilityFees" abstract="false" name="FacilityFees" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gbdc4_LongTermDebtGrossMaturityLessThan1Year" abstract="false" name="LongTermDebtGrossMaturityLessThan1Year" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gbdc4_LongTermDebtGrossMaturity1Through3Years" abstract="false" name="LongTermDebtGrossMaturity1Through3Years" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gbdc4_LongTermDebtGrossMaturity3Through5Years" abstract="false" name="LongTermDebtGrossMaturity3Through5Years" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gbdc4_LongTermDebtGrossMaturityMoreThan5Years" abstract="false" name="LongTermDebtGrossMaturityMoreThan5Years" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gbdc4_AdjustmentToDistributableEarningsLoss" abstract="false" name="AdjustmentToDistributableEarningsLoss" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gbdc4_InvestmentCompanyDistributableEarningsLossAccumulatedOtherTemporaryDifferences" abstract="false" name="InvestmentCompanyDistributableEarningsLossAccumulatedOtherTemporaryDifferences" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="gbdc4_UndrawnRevolverMember" abstract="true" name="UndrawnRevolverMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_CapitalGainMember" abstract="true" name="CapitalGainMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_InvestmentCompanyTotalExpensesToAverageNetAssets" abstract="false" name="InvestmentCompanyTotalExpensesToAverageNetAssets" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gbdc4_InvestmentCompanyManagementFeeWaiverRatioToAverageNetAssets" abstract="false" name="InvestmentCompanyManagementFeeWaiverRatioToAverageNetAssets" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gbdc4_InvestmentCompanyIncentiveFeeWaiverToAverageNetAssets" abstract="false" name="InvestmentCompanyIncentiveFeeWaiverToAverageNetAssets" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gbdc4_InvestmentCompanyOperatingExpenseWaiverToAverageNetAssets" abstract="false" name="InvestmentCompanyOperatingExpenseWaiverToAverageNetAssets" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gbdc4_InvestmentCompanyExciseTaxToAverageNetAssets" abstract="false" name="InvestmentCompanyExciseTaxToAverageNetAssets" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gbdc4_InvestmentCompanyNetExpensesToAverageNetAssets" abstract="false" name="InvestmentCompanyNetExpensesToAverageNetAssets" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gbdc4_InvestmentCompanyExpenseRatioBeforeIncentiveFees" abstract="false" name="InvestmentCompanyExpenseRatioBeforeIncentiveFees" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="gbdc4_LongTermDebtAverageAmountOutstandingPerShare" abstract="false" name="LongTermDebtAverageAmountOutstandingPerShare" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="gbdc4_InvestmentCompanySeniorSecurityIndebtednessAssetCoverageRatioPerUnit" abstract="false" name="InvestmentCompanySeniorSecurityIndebtednessAssetCoverageRatioPerUnit" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="gbdc4_O2025M1DividendsMember" abstract="true" name="O2025M1DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2025M2DividendsMember" abstract="true" name="O2025M2DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2025M3DividendsMember" abstract="true" name="O2025M3DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2025M4DividendsMember" abstract="true" name="O2025M4DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2025M5DividendsMember" abstract="true" name="O2025M5DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2025M6DividendsMember" abstract="true" name="O2025M6DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2025M7DividendsMember" abstract="true" name="O2025M7DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2025M8DividendsMember" abstract="true" name="O2025M8DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2025M9DividendsMember" abstract="true" name="O2025M9DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2025M10DividendsMember" abstract="true" name="O2025M10DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2025M11DividendsMember" abstract="true" name="O2025M11DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2025M12DividendsMember" abstract="true" name="O2025M12DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2024M1DividendsMember" abstract="true" name="O2024M1DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2024M2DividendsMember" abstract="true" name="O2024M2DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2024M3DividendsMember" abstract="true" name="O2024M3DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2024M4DividendsMember" abstract="true" name="O2024M4DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2024M5DividendsMember" abstract="true" name="O2024M5DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2024M6DividendsMember" abstract="true" name="O2024M6DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2024M7DividendsMember" abstract="true" name="O2024M7DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2024M8DividendsMember" abstract="true" name="O2024M8DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2024M9DividendsMember" abstract="true" name="O2024M9DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2024M10DividendsMember" abstract="true" name="O2024M10DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2024M11DividendsMember" abstract="true" name="O2024M11DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2024M12DividendsMember" abstract="true" name="O2024M12DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2023M1DividendsMember" abstract="true" name="O2023M1DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2023M2DividendsMember" abstract="true" name="O2023M2DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2023M3DividendsMember" abstract="true" name="O2023M3DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2023M4DividendsMember" abstract="true" name="O2023M4DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2023M5DividendsMember" abstract="true" name="O2023M5DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2023M6DividendsMember" abstract="true" name="O2023M6DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2023M7DividendsMember" abstract="true" name="O2023M7DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2023M8DividendsMember" abstract="true" name="O2023M8DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2023M9DividendsMember" abstract="true" name="O2023M9DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2023M10DividendsMember" abstract="true" name="O2023M10DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2023M11DividendsMember" abstract="true" name="O2023M11DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2023M12DividendsMember" abstract="true" name="O2023M12DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2025M31DividendsMember" abstract="true" name="O2025M31DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2025M32DividendsMember" abstract="true" name="O2025M32DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2025M51DividendsMember" abstract="true" name="O2025M51DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2025M52DividendsMember" abstract="true" name="O2025M52DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2023M61DividendsMember" abstract="true" name="O2023M61DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_O2023M62DividendsMember" abstract="true" name="O2023M62DividendsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="gbdc4_AdvisorRevolverMember" abstract="true" name="AdvisorRevolverMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
