diff --git a/pkg/apis/core/types.go b/pkg/apis/core/types.go
index a75ae941fa1..5280cae0d9f 100644
--- a/pkg/apis/core/types.go
+++ b/pkg/apis/core/types.go
@@ -575,7 +575,7 @@ type GCEPersistentDiskVolumeSource struct {
 	PDName string
 	// Filesystem type to mount.
 	// Must be a filesystem type supported by the host operating system.
-	// Ex. "ext4", "xfs", "ntfs". Implicitly inferred to be "ext4" if unspecified.
+	// Ex. "ext4", "xfs", "ntfs".
 	// TODO: how do we prevent errors in the filesystem from compromising the machine
 	// +optional
 	FSType string
diff --git a/pkg/volume/csi/csi_attacher.go b/pkg/volume/csi/csi_attacher.go
index ec384de815d..1709bbac0f8 100644
--- a/pkg/volume/csi/csi_attacher.go
+++ b/pkg/volume/csi/csi_attacher.go
@@ -354,10 +354,6 @@ func (c *csiAttacher) MountDevice(spec *volume.Spec, devicePath string, deviceMo
 	}
 
 	fsType := csiSource.FSType
-	if len(fsType) == 0 {
-		fsType = defaultFSType
-	}
-
 	err = csi.NodeStageVolume(ctx,
 		csiSource.VolumeHandle,
 		publishVolumeInfo,
diff --git a/pkg/volume/csi/csi_mounter.go b/pkg/volume/csi/csi_mounter.go
index b6d86956d15..57700895d26 100644
--- a/pkg/volume/csi/csi_mounter.go
+++ b/pkg/volume/csi/csi_mounter.go
@@ -34,8 +34,6 @@ import (
 	"k8s.io/kubernetes/pkg/volume/util"
 )
 
-const defaultFSType = "ext4"
-
 //TODO (vladimirvivien) move this in a central loc later
 var (
 	volDataKey = struct {
@@ -177,9 +175,6 @@ func (c *csiMountMgr) SetUpAt(dir string, fsGroup *int64) error {
 	}
 
 	fsType := csiSource.FSType
-	if len(fsType) == 0 {
-		fsType = defaultFSType
-	}
 	err = csi.NodePublishVolume(
 		ctx,
 		c.volumeID,
diff --git a/pkg/volume/csi/csi_mounter_test.go b/pkg/volume/csi/csi_mounter_test.go
index d1e942871d0..88b2b1a2d56 100644
--- a/pkg/volume/csi/csi_mounter_test.go
+++ b/pkg/volume/csi/csi_mounter_test.go
@@ -144,6 +144,12 @@ func TestMounterSetUp(t *testing.T) {
 	if err := csiMounter.SetUp(&fsGroup); err != nil {
 		t.Fatalf("mounter.Setup failed: %v", err)
 	}
+
+	//Test the default value of file system type is not overridden
+	if len(csiMounter.spec.PersistentVolume.Spec.CSI.FSType) != 0 {
+		t.Errorf("default value of file system type was overridden by type %s", csiMounter.spec.PersistentVolume.Spec.CSI.FSType)
+	}
+
 	path := csiMounter.GetPath()
 	if _, err := os.Stat(path); err != nil {
 		if os.IsNotExist(err) {
diff --git a/staging/src/k8s.io/api/core/v1/types.go b/staging/src/k8s.io/api/core/v1/types.go
index 99159ee75a6..8967c602c6e 100644
--- a/staging/src/k8s.io/api/core/v1/types.go
+++ b/staging/src/k8s.io/api/core/v1/types.go
@@ -635,7 +635,7 @@ type RBDVolumeSource struct {
 	RBDImage string `json:"image" protobuf:"bytes,2,opt,name=image"`
 	// Filesystem type of the volume that you want to mount.
 	// Tip: Ensure that the filesystem type is supported by the host operating system.
-	// Examples: "ext4", "xfs", "ntfs". Implicitly inferred to be "ext4" if unspecified.
+	// Examples: "ext4", "xfs", "ntfs".
 	// More info: https://kubernetes.io/docs/concepts/storage/volumes#rbd
 	// TODO: how do we prevent errors in the filesystem from compromising the machine
 	// +optional