diff --git a/src/lib/snack-bar/snack-bar.spec.ts b/src/lib/snack-bar/snack-bar.spec.ts
index 76e085c494c5..928bb1d3d4ec 100644
--- a/src/lib/snack-bar/snack-bar.spec.ts
+++ b/src/lib/snack-bar/snack-bar.spec.ts
@@ -329,10 +329,8 @@ describe('MdSnackBar', () => {
   }));
 
   it('should add extra classes to the container', () => {
-    snackBar.open(simpleMessage, simpleActionLabel, {
-      viewContainerRef: testViewContainerRef,
-      extraClasses: ['one', 'two']
-    });
+    snackBar.open(simpleMessage, simpleActionLabel, { extraClasses: ['one', 'two'] });
+    viewContainerFixture.detectChanges();
 
     let containerClasses = overlayContainerElement.querySelector('snack-bar-container').classList;
 
@@ -342,6 +340,7 @@ describe('MdSnackBar', () => {
 
   it('should set the layout direction', () => {
     snackBar.open(simpleMessage, simpleActionLabel, { direction: 'rtl' });
+    viewContainerFixture.detectChanges();
 
     let pane = overlayContainerElement.querySelector('.cdk-overlay-pane');