diff --git a/spec/operators/groupBy-spec.ts b/spec/operators/groupBy-spec.ts
index 5a6d35d75f..6e4adf2771 100644
--- a/spec/operators/groupBy-spec.ts
+++ b/spec/operators/groupBy-spec.ts
@@ -903,6 +903,39 @@ describe('Observable.prototype.groupBy', () => {
     expectObservable(source, unsub).toBe(expected, expectedGroups);
   });
 
+  it('should dispose a durationSelector after closing the group',
+  () => {
+    const obs = hot('-0-1--------2-|');
+    const sub =     '^              !' ;
+    let unsubs = [
+                    '-^--!',
+                    '---^--!',
+                    '------------^-!',
+    ];
+    const dur =     '---s';
+    const durations = [
+      cold(dur),
+      cold(dur),
+      cold(dur)
+    ];
+
+    const unsubscribedFrame = Rx.TestScheduler
+      .parseMarblesAsSubscriptions(sub)
+      .unsubscribedFrame;
+
+    obs.groupBy(
+      (val: string) => val,
+      (val: string) => val,
+      (group: any) => durations[group.key]
+    ).subscribe();
+
+    rxTestScheduler.schedule(() => {
+      durations.forEach((d, i) => {
+        expectSubscriptions(d.subscriptions).toBe(unsubs[i]);
+      });
+    }, unsubscribedFrame);
+  });
+
   it('should allow using a durationSelector, but keySelector throws', () => {
     const values = {
       a: '  foo',
diff --git a/src/operator/groupBy.ts b/src/operator/groupBy.ts
index c3f4ae8e8f..de801caf17 100644
--- a/src/operator/groupBy.ts
+++ b/src/operator/groupBy.ts
@@ -227,27 +227,19 @@ class GroupDurationSubscriber<K, T> extends Subscriber<T> {
   constructor(private key: K,
               private group: Subject<T>,
               private parent: GroupBySubscriber<any, K, T>) {
-    super();
+    super(group);
   }
 
   protected _next(value: T): void {
-    this._complete();
-  }
-
-  protected _error(err: any): void {
-    const group = this.group;
-    if (!group.closed) {
-      group.error(err);
-    }
-    this.parent.removeGroup(this.key);
+    this.complete();
   }
 
-  protected _complete(): void {
-    const group = this.group;
-    if (!group.closed) {
-      group.complete();
+  protected _unsubscribe() {
+    const { parent, key } = this;
+    this.key = this.parent = null;
+    if (parent) {
+      parent.removeGroup(key);
     }
-    this.parent.removeGroup(this.key);
   }
 }