diff --git a/cluster/common.sh b/cluster/common.sh
index 3f5828a07b..6cfbc8cf8d 100755
--- a/cluster/common.sh
+++ b/cluster/common.sh
@@ -647,7 +647,7 @@ MANIFEST_URL: $(yaml-quote ${MANIFEST_URL:-})
 MANIFEST_URL_HEADER: $(yaml-quote ${MANIFEST_URL_HEADER:-})
 NUM_NODES: $(yaml-quote ${NUM_NODES})
 STORAGE_BACKEND: $(yaml-quote ${STORAGE_BACKEND:-})
-ENABLE_GARBAGE_COLLECTOR: $(yaml-quote ${ENABLE_GARBAGE_COLLECTOR:-false})
+ENABLE_GARBAGE_COLLECTOR: $(yaml-quote ${ENABLE_GARBAGE_COLLECTOR:-})
 EOF
     if [ -n "${APISERVER_TEST_ARGS:-}" ]; then
       cat >>$file <<EOF
diff --git a/cmd/kube-apiserver/app/options/options.go b/cmd/kube-apiserver/app/options/options.go
index 224ba0ccb4..dc051ffeaa 100644
--- a/cmd/kube-apiserver/app/options/options.go
+++ b/cmd/kube-apiserver/app/options/options.go
@@ -124,7 +124,7 @@ func (s *APIServer) AddFlags(fs *pflag.FlagSet) {
 		"e.g., setting empty UID in update request to its existing value. This flag can be turned off "+
 		"after we fix all the clients that send malformed updates.")
 
-	fs.BoolVar(&registry.EnableGarbageCollector, "enable-garbage-collector", false, ""+
+	fs.BoolVar(&registry.EnableGarbageCollector, "enable-garbage-collector", true, ""+
 		"Enables the generic garbage collector. MUST be synced with the corresponding flag "+
 		"of the kube-controller-manager.")
 }
diff --git a/cmd/kube-controller-manager/app/options/options.go b/cmd/kube-controller-manager/app/options/options.go
index 1545d16fc4..3c5fae5cc7 100644
--- a/cmd/kube-controller-manager/app/options/options.go
+++ b/cmd/kube-controller-manager/app/options/options.go
@@ -92,8 +92,8 @@ func NewCMServer() *CMServer {
 			KubeAPIBurst:            30,
 			LeaderElection:          leaderelection.DefaultLeaderElectionConfiguration(),
 			ControllerStartInterval: unversioned.Duration{Duration: 0 * time.Second},
-			EnableGarbageCollector:  false,
-			ConcurrentGCSyncs:       100,
+			EnableGarbageCollector:  true,
+			ConcurrentGCSyncs:       20,
 			ClusterSigningCertFile:  "/etc/kubernetes/ca/ca.pem",
 			ClusterSigningKeyFile:   "/etc/kubernetes/ca/ca.key",
 		},
@@ -172,7 +172,7 @@ func (s *CMServer) AddFlags(fs *pflag.FlagSet) {
 	fs.Float32Var(&s.KubeAPIQPS, "kube-api-qps", s.KubeAPIQPS, "QPS to use while talking with kubernetes apiserver")
 	fs.Int32Var(&s.KubeAPIBurst, "kube-api-burst", s.KubeAPIBurst, "Burst to use while talking with kubernetes apiserver")
 	fs.DurationVar(&s.ControllerStartInterval.Duration, "controller-start-interval", s.ControllerStartInterval.Duration, "Interval between starting controller managers.")
-	fs.BoolVar(&s.EnableGarbageCollector, "enable-garbage-collector", s.EnableGarbageCollector, "Enables the generic garbage collector. MUST be synced with the corresponding flag of the kube-apiserver. WARNING: the generic garbage collector is an alpha feature.")
+	fs.BoolVar(&s.EnableGarbageCollector, "enable-garbage-collector", s.EnableGarbageCollector, "Enables the generic garbage collector. MUST be synced with the corresponding flag of the kube-apiserver.")
 	fs.Int32Var(&s.ConcurrentGCSyncs, "concurrent-gc-syncs", s.ConcurrentGCSyncs, "The number of garbage collector workers that are allowed to sync concurrently.")
 	fs.Float32Var(&s.NodeEvictionRate, "node-eviction-rate", 0.1, "Number of nodes per second on which pods are deleted in case of node failure when a zone is healthy (see --unhealthy-zone-threshold for definition of healthy/unhealthy). Zone refers to entire cluster in non-multizone clusters.")
 	fs.Float32Var(&s.SecondaryNodeEvictionRate, "secondary-node-eviction-rate", 0.01, "Number of nodes per second on which pods are deleted in case of node failure when a zone is unhealthy (see --unhealthy-zone-threshold for definition of healthy/unhealthy). Zone refers to entire cluster in non-multizone clusters. This value is implicitly overridden to 0 if the cluster size is smaller than --large-cluster-size-threshold.")