diff --git a/dom/push/PushServiceWebSocket.jsm b/dom/push/PushServiceWebSocket.jsm
index 45f67a6c0557..f2dbdb557428 100644
--- a/dom/push/PushServiceWebSocket.jsm
+++ b/dom/push/PushServiceWebSocket.jsm
@@ -170,11 +170,6 @@ this.PushServiceWebSocket = {
 
     if (timer == this._backoffTimer) {
       console.debug("onTimerFired: Reconnecting after backoff");
-      if (this._reconnectTestCallback) {
-        // Notify the test callback once the client reconnects.
-        let actualRetryTimeout = Date.now() - this._lastDisconnect;
-        this._reconnectTestCallback(actualRetryTimeout);
-      }
       this._beginWSSetup();
       return;
     }
@@ -331,9 +326,6 @@ this.PushServiceWebSocket = {
    */
   _lastPingTime: 0,
 
-  /** The last time the connection was closed. */
-  _lastDisconnect: 0,
-
   /**
    * A one-shot timer used to ping the server, to avoid timing out idle
    * connections. Reset to the ping interval on each incoming message.
@@ -343,15 +335,6 @@ this.PushServiceWebSocket = {
   /** A one-shot timer fired after the reconnect backoff period. */
   _backoffTimer: null,
 
-  /**
-   * A function called when the client reconnects after backing off.
-   *
-   * @param {Number} actualRetryTimeout The time elapsed between the last
-   *  disconnect and reconnect time. This should be >= the backoff delay for
-   *  that attempt.
-   */
-  _reconnectTestCallback: null,
-
   /**
    * Sends a message to the Push Server through an open websocket.
    * typeof(msg) shall be an object
@@ -434,8 +417,6 @@ this.PushServiceWebSocket = {
       this._notifyRequestQueue();
       this._notifyRequestQueue = null;
     }
-
-    this._lastDisconnect = Date.now();
   },
 
   uninit: function() {
diff --git a/dom/push/test/xpcshell/test_retry_ws.js b/dom/push/test/xpcshell/test_retry_ws.js
index 32471a408331..e81e54c7dd82 100644
--- a/dom/push/test/xpcshell/test_retry_ws.js
+++ b/dom/push/test/xpcshell/test_retry_ws.js
@@ -11,7 +11,7 @@ function run_test() {
   do_get_profile();
   setPrefs({
     userAgentID: userAgentID,
-    pingInterval: 10000,
+    pingInterval: 2000,
     retryBaseInterval: 25,
   });
   run_next_test();
@@ -30,9 +30,17 @@ add_task(function* test_ws_retry() {
     quota: Infinity,
   });
 
-  let alarmDelays = [];
-  PushServiceWebSocket._reconnectTestCallback = function(delay) {
-    alarmDelays.push(delay);
+  // Use a mock timer to avoid waiting for the backoff interval.
+  let reconnects = 0;
+  PushServiceWebSocket._backoffTimer = {
+    init(observer, delay, type) {
+      reconnects++;
+      ok(delay >= 5 && delay <= 2000, `Backoff delay ${
+        delay} out of range for attempt ${reconnects}`);
+      observer.observe(this, "timer-callback", null);
+    },
+
+    cancel() {},
   };
 
   let handshakeDone;
@@ -43,7 +51,7 @@ add_task(function* test_ws_retry() {
     makeWebSocket(uri) {
       return new MockWebSocket(uri, {
         onHello(request) {
-          if (alarmDelays.length == 10) {
+          if (reconnects == 10) {
             this.serverSendMsg(JSON.stringify({
               messageType: 'hello',
               status: 200,
@@ -59,8 +67,4 @@ add_task(function* test_ws_retry() {
   });
 
   yield handshakePromise;
-  [25, 50, 100, 200, 400, 800, 1600, 3200, 6400, 10000].forEach(function(minDelay, index) {
-    ok(alarmDelays[index] >= minDelay, `Should wait at least ${
-      minDelay}ms before attempt ${index + 1}`);
-  });
 });