diff --git a/klippy/clocksync.py b/klippy/clocksync.py
index 06835618..5dffc215 100644
--- a/klippy/clocksync.py
+++ b/klippy/clocksync.py
@@ -14,7 +14,7 @@ class ClockSync:
         self.reactor = reactor
         self.serial = None
         self.get_clock_timer = reactor.register_timer(self._get_clock_event)
-        self.get_clock_cmd = None
+        self.get_clock_cmd = self.cmd_queue = None
         self.queries_pending = 0
         self.mcu_freq = 1.
         self.last_clock = 0
@@ -31,19 +31,19 @@ class ClockSync:
         self.serial = serial
         self.mcu_freq = serial.msgparser.get_constant_float('CLOCK_FREQ')
         # Load initial clock and frequency
-        get_uptime_cmd = serial.lookup_command('get_uptime')
-        params = get_uptime_cmd.send_with_response(response='uptime')
+        params = serial.send_with_response('get_uptime', 'uptime')
         self.last_clock = (params['high'] << 32) | params['clock']
         self.clock_avg = self.last_clock
         self.time_avg = params['#sent_time']
         self.clock_est = (self.time_avg, self.clock_avg, self.mcu_freq)
         self.prediction_variance = (.001 * self.mcu_freq)**2
         # Enable periodic get_clock timer
-        self.get_clock_cmd = serial.lookup_command('get_clock')
         for i in range(8):
-            params = self.get_clock_cmd.send_with_response(response='clock')
+            params = serial.send_with_response('get_clock', 'clock')
             self._handle_clock(params)
             self.reactor.pause(0.100)
+        self.get_clock_cmd = serial.get_msgparser().create_command('get_clock')
+        self.cmd_queue = serial.alloc_command_queue()
         serial.register_response(self._handle_clock, 'clock')
         self.reactor.update_timer(self.get_clock_timer, self.reactor.NOW)
     def connect_file(self, serial, pace=False):
@@ -56,7 +56,7 @@ class ClockSync:
         serial.set_clock_est(freq, self.reactor.monotonic(), 0)
     # MCU clock querying (_handle_clock is invoked from background thread)
     def _get_clock_event(self, eventtime):
-        self.get_clock_cmd.send()
+        self.serial.raw_send(self.get_clock_cmd, 0, 0, self.cmd_queue)
         self.queries_pending += 1
         # Use an unusual time for the next event so clock messages
         # don't resonate with other periodic events.
diff --git a/klippy/serialhdl.py b/klippy/serialhdl.py
index 6284fe4d..020a3f27 100644
--- a/klippy/serialhdl.py
+++ b/klippy/serialhdl.py
@@ -52,10 +52,9 @@ class SerialReader:
     def _get_identify_data(self, timeout):
         # Query the "data dictionary" from the micro-controller
         identify_data = ""
-        identify_cmd = self.lookup_command("identify offset=%u count=%c")
         while 1:
-            params = identify_cmd.send_with_response([len(identify_data), 40],
-                                                     'identify_response')
+            msg = "identify offset=%d count=%d" % (len(identify_data), 40)
+            params = self.send_with_response(msg, 'identify_response')
             if params['offset'] == len(identify_data):
                 msgdata = params['data']
                 if not msgdata:
@@ -149,6 +148,10 @@ class SerialReader:
     def send(self, msg, minclock=0, reqclock=0):
         cmd = self.msgparser.create_command(msg)
         self.raw_send(cmd, minclock, reqclock, self.default_cmd_queue)
+    def send_with_response(self, msg, response):
+        cmd = self.msgparser.create_command(msg)
+        src = SerialRetryCommand(self, cmd, response)
+        return src.get_response()
     def lookup_command(self, msgformat, cq=None):
         if cq is None:
             cq = self.default_cmd_queue