diff --git a/build/test.mk b/build/test.mk
index 0a68676334..185681c4ff 100644
--- a/build/test.mk
+++ b/build/test.mk
@@ -4,7 +4,7 @@
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at
-#    
+#
 #     http://www.apache.org/licenses/LICENSE-2.0
 #
 # Unless required by applicable law or agreed to in writing, software
@@ -86,76 +86,76 @@ test-functional-ucp: test-functional-ucp-noncloud test-functional-ucp-cloud ## R
 
 .PHONY: test-functional-ucp-noncloud
 test-functional-ucp-noncloud: ## Runs UCP functional tests that do not require cloud resources
-	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/ucp/noncloud/... -timeout ${TEST_TIMEOUT} -v -parallel 5 $(GOTEST_OPTS)
+	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/ucp/noncloud/... -timeout ${TEST_TIMEOUT} -v -p 4 $(GOTEST_OPTS)
 
 .PHONY: test-functional-ucp-cloud
 test-functional-ucp-cloud: ## Runs UCP functional tests that require cloud resources
-	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/ucp/cloud/... -timeout ${TEST_TIMEOUT} -v -parallel 5 $(GOTEST_OPTS)
+	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/ucp/cloud/... -timeout ${TEST_TIMEOUT} -v -p 2 $(GOTEST_OPTS)
 
 .PHONY: test-functional-kubernetes
 test-functional-kubernetes: test-functional-kubernetes-noncloud ## Runs all Kubernetes functional tests
-	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/kubernetes/... -timeout ${TEST_TIMEOUT} -v -parallel 5 $(GOTEST_OPTS)
+	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/kubernetes/... -timeout ${TEST_TIMEOUT} -v -p 1 $(GOTEST_OPTS)
 
 .PHONY: test-functional-kubernetes-noncloud
 test-functional-kubernetes-noncloud: ## Runs Kubernetes functional tests that do not require cloud resources
-	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/kubernetes/noncloud/... -timeout ${TEST_TIMEOUT} -v -parallel 5 $(GOTEST_OPTS)
+	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/kubernetes/noncloud/... -timeout ${TEST_TIMEOUT} -v -p 1 $(GOTEST_OPTS)
 
 .PHONY: test-functional-corerp
 test-functional-corerp: test-functional-corerp-noncloud test-functional-corerp-cloud ## Runs all Core RP functional tests (both cloud and non-cloud)
 
 .PHONY: test-functional-corerp-noncloud
 test-functional-corerp-noncloud: ## Runs corerp functional tests that do not require cloud resources
-	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/corerp/noncloud/... -timeout ${TEST_TIMEOUT} -v -parallel 10 $(GOTEST_OPTS)
+	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/corerp/noncloud/... -timeout ${TEST_TIMEOUT} -v -p 3 $(GOTEST_OPTS)
 
 .PHONY: test-functional-corerp-cloud
 test-functional-corerp-cloud: ## Runs corerp functional tests that require cloud resources
-	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/corerp/cloud/... -timeout ${TEST_TIMEOUT} -v -parallel 10 $(GOTEST_OPTS)
+	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/corerp/cloud/... -timeout ${TEST_TIMEOUT} -v -p 2 $(GOTEST_OPTS)
 
 .PHONY: test-functional-msgrp
 test-functional-msgrp: test-functional-msgrp-noncloud ## Runs all Messaging RP functional tests (both cloud and non-cloud)
 
 .PHONY: test-functional-msgrp-noncloud
 test-functional-msgrp-noncloud: ## Runs Messaging RP functional tests that do not require cloud resources
-	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/messagingrp/noncloud/... -timeout ${TEST_TIMEOUT} -v -parallel 2 $(GOTEST_OPTS)
+	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/messagingrp/noncloud/... -timeout ${TEST_TIMEOUT} -v -p 2 $(GOTEST_OPTS)
 
 .PHONY: test-functional-cli
 test-functional-cli: test-functional-cli-noncloud ## Runs all cli functional tests (both cloud and non-cloud)
 
 .PHONY: test-functional-cli-noncloud
 test-functional-cli-noncloud: ## Runs cli functional tests that do not require cloud resources
-	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/cli/noncloud/... -timeout ${TEST_TIMEOUT} -v -parallel 10 $(GOTEST_OPTS)
+	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/cli/noncloud/... -timeout ${TEST_TIMEOUT} -v -p 4 $(GOTEST_OPTS)
 
 .PHONY: test-functional-daprrp
 test-functional-daprrp: test-functional-daprrp-noncloud ## Runs all Dapr RP functional tests (both cloud and non-cloud)
 
 .PHONY: test-functional-daprrp-noncloud
 test-functional-daprrp-noncloud: ## Runs Dapr RP functional tests that do not require cloud resources
-	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/daprrp/noncloud/... -timeout ${TEST_TIMEOUT} -v -parallel 3 $(GOTEST_OPTS)
+	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/daprrp/noncloud/... -timeout ${TEST_TIMEOUT} -v -p 2 $(GOTEST_OPTS)
 
 .PHONY: test-functional-datastoresrp
 test-functional-datastoresrp: test-functional-datastoresrp-noncloud ## Runs all Datastores RP functional tests (non-cloud)
 
 .PHONY: test-functional-datastoresrp-noncloud
 test-functional-datastoresrp-noncloud: ## Runs Datastores RP functional tests that do not require cloud resources
-	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/datastoresrp/noncloud/... -timeout ${TEST_TIMEOUT} -v -parallel 3 $(GOTEST_OPTS)
+	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/datastoresrp/noncloud/... -timeout ${TEST_TIMEOUT} -v -p 3 $(GOTEST_OPTS)
 
 .PHONY: test-functional-dynamicrp-noncloud
 test-functional-dynamicrp-noncloud: ## Runs Dynamic RP functional tests that do not require cloud resources
-	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/dynamicrp/noncloud/... -timeout ${TEST_TIMEOUT} -v -parallel 1 $(GOTEST_OPTS)
+	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/dynamicrp/noncloud/... -timeout ${TEST_TIMEOUT} -v -parallel 1 -p 1 $(GOTEST_OPTS)
 
 .PHONY: test-functional-upgrade
 test-functional-upgrade: test-functional-upgrade-noncloud ## Runs all Upgrade functional tests
 
 .PHONY: test-functional-upgrade-noncloud
 test-functional-upgrade-noncloud: ## Runs Upgrade functional tests that do not require cloud resources
-	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/upgrade/... -timeout ${TEST_TIMEOUT} -v -parallel 1 $(GOTEST_OPTS)
-	
+	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/upgrade/... -timeout ${TEST_TIMEOUT} -v -parallel 1 -p 1 $(GOTEST_OPTS)
+
 .PHONY: test-functional-samples
 test-functional-samples: test-functional-samples-noncloud ## Runs all Samples functional tests
 
 .PHONY: test-functional-samples-noncloud
 test-functional-samples-noncloud: ## Runs Samples functional tests that do not require cloud resources
-	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/samples/noncloud/... -timeout ${TEST_TIMEOUT} -v -parallel 5 $(GOTEST_OPTS)
+	CGO_ENABLED=1 $(GOTEST_TOOL) ./test/functional-portable/samples/noncloud/... -timeout ${TEST_TIMEOUT} -v -p 4 $(GOTEST_OPTS)
 
 .PHONY: test-validate-bicep
 test-validate-bicep: ## Validates that all .bicep files compile cleanly
@@ -175,7 +175,7 @@ oav-installed:
 	@echo "$(ARROW) OK"
 
 # TODO re-enable https://github.com/radius-project/radius/issues/5091
-.PHONY: test-ucp-spec-examples 
+.PHONY: test-ucp-spec-examples
 test-ucp-spec-examples: oav-installed ## Validates UCP examples conform to UCP OpenAPI Spec
 	# @echo "$(ARROW) Testing x-ms-examples conform to ucp spec..."
 	# oav validate-example swagger/specification/ucp/resource-manager/UCP/preview/2023-10-01-preview/openapi.json
diff --git a/test/functional-portable/upgrade/upgrade_test.go b/test/functional-portable/upgrade/upgrade_test.go
index 7081fee5b1..faa1eadf2e 100644
--- a/test/functional-portable/upgrade/upgrade_test.go
+++ b/test/functional-portable/upgrade/upgrade_test.go
@@ -114,7 +114,11 @@ func Test_PreflightContainer_PreflightDisabled(t *testing.T) {
 	_ = exec.Command(cleanupCommand[0], cleanupCommand[1:]...).Run() // Ignore errors during cleanup
 
 	// Wait for cleanup to complete
-	time.Sleep(3 * time.Second)
+	require.Eventually(t, func() bool {
+		cmd := exec.Command("helm", "status", "radius", "--namespace", radiusNamespace)
+		err := cmd.Run()
+		return err != nil
+	}, 30*time.Second, 1*time.Second, "Radius release was not uninstalled")
 
 	t.Log("Installing Radius with preflight disabled using helm")
 	installCommand := []string{
@@ -180,7 +184,11 @@ func Test_PreflightContainer_JobConfiguration(t *testing.T) {
 	_ = exec.Command(cleanupCommand[0], cleanupCommand[1:]...).Run() // Ignore errors during cleanup
 
 	// Wait for cleanup to complete
-	time.Sleep(3 * time.Second)
+	require.Eventually(t, func() bool {
+		cmd := exec.Command("helm", "status", "radius", "--namespace", radiusNamespace)
+		err := cmd.Run()
+		return err != nil
+	}, 30*time.Second, 1*time.Second, "Radius release was not uninstalled")
 
 	// Use local registry image for testing
 	t.Log("Installing Radius with custom preflight configuration using helm")