diff --git a/keystone/tests/core.py b/keystone/tests/core.py
index a762315639..33e566e70a 100644
--- a/keystone/tests/core.py
+++ b/keystone/tests/core.py
@@ -63,7 +63,6 @@ from keystone.openstack.common.db.sqlalchemy import migration
 from keystone.openstack.common.db.sqlalchemy import session
 from keystone.openstack.common.fixture import config as config_fixture
 from keystone.openstack.common import log
-from keystone.openstack.common import timeutils
 from keystone import service
 from keystone.tests import fixtures as ksfixtures
 
@@ -348,8 +347,6 @@ class TestCase(testtools.TestCase):
 
         self.addCleanup(kvs.INMEMDB.clear)
 
-        self.addCleanup(timeutils.clear_time_override)
-
         # Ensure Notification subscriotions and resource types are empty
         self.addCleanup(notifications.SUBSCRIBERS.clear)
         self.addCleanup(notifications._reset_notifier)
diff --git a/keystone/tests/test_auth.py b/keystone/tests/test_auth.py
index 76561c1661..11b1a42bfa 100644
--- a/keystone/tests/test_auth.py
+++ b/keystone/tests/test_auth.py
@@ -16,6 +16,8 @@ import copy
 import datetime
 import uuid
 
+import mock
+
 from keystone import assignment
 from keystone import auth
 from keystone.common import authorization
@@ -911,9 +913,12 @@ class AuthWithTrust(AuthTest):
 
 
 class TokenExpirationTest(AuthTest):
-    def _maintain_token_expiration(self):
+
+    @mock.patch.object(timeutils, 'utcnow')
+    def _maintain_token_expiration(self, mock_utcnow):
         """Token expiration should be maintained after re-auth & validation."""
-        timeutils.set_time_override()
+        now = datetime.datetime.utcnow()
+        mock_utcnow.return_value = now
 
         r = self.controller.authenticate(
             {},
@@ -926,14 +931,14 @@ class TokenExpirationTest(AuthTest):
         unscoped_token_id = r['access']['token']['id']
         original_expiration = r['access']['token']['expires']
 
-        timeutils.advance_time_seconds(1)
+        mock_utcnow.return_value = now + datetime.timedelta(seconds=1)
 
         r = self.controller.validate_token(
             dict(is_admin=True, query_string={}),
             token_id=unscoped_token_id)
         self.assertEqual(original_expiration, r['access']['token']['expires'])
 
-        timeutils.advance_time_seconds(1)
+        mock_utcnow.return_value = now + datetime.timedelta(seconds=2)
 
         r = self.controller.authenticate(
             {},
@@ -946,7 +951,7 @@ class TokenExpirationTest(AuthTest):
         scoped_token_id = r['access']['token']['id']
         self.assertEqual(original_expiration, r['access']['token']['expires'])
 
-        timeutils.advance_time_seconds(1)
+        mock_utcnow.return_value = now + datetime.timedelta(seconds=3)
 
         r = self.controller.validate_token(
             dict(is_admin=True, query_string={}),
diff --git a/keystone/tests/test_keystoneclient.py b/keystone/tests/test_keystoneclient.py
index abce4277c4..70c82de499 100644
--- a/keystone/tests/test_keystoneclient.py
+++ b/keystone/tests/test_keystoneclient.py
@@ -12,10 +12,13 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
+import datetime
 import os
 import uuid
 import webob
 
+import mock
+
 from keystone.common import sql
 from keystone import config
 from keystone.openstack.common.db.sqlalchemy import session
@@ -530,12 +533,14 @@ class KeystoneClientTests(object):
                           client.tokens.authenticate,
                           token=token_id)
 
-    def test_token_expiry_maintained(self):
-        timeutils.set_time_override()
+    @mock.patch.object(timeutils, 'utcnow')
+    def test_token_expiry_maintained(self, mock_utcnow):
+        now = datetime.datetime.utcnow()
+        mock_utcnow.return_value = now
         foo_client = self.get_client(self.user_foo)
 
         orig_token = foo_client.service_catalog.catalog['token']
-        timeutils.advance_time_seconds(1)
+        mock_utcnow.return_value = now + datetime.timedelta(seconds=1)
         reauthenticated_token = foo_client.tokens.authenticate(
             token=foo_client.auth_token)