diff --git a/selfdrive/test/test_onroad.py b/selfdrive/test/test_onroad.py
index fe7876d1b2..23d1687770 100644
--- a/selfdrive/test/test_onroad.py
+++ b/selfdrive/test/test_onroad.py
@@ -23,7 +23,6 @@ from openpilot.selfdrive.test.helpers import set_params_enabled, release_only
 from openpilot.system.hardware import HARDWARE
 from openpilot.system.hardware.hw import Paths
 from openpilot.tools.lib.logreader import LogReader
-from openpilot.tools.lib.log_time_series import msgs_to_time_series
 
 """
 CPU usage budget
@@ -120,8 +119,7 @@ class TestOnroad:
     if "DEBUG" in os.environ:
       segs = filter(lambda x: os.path.exists(os.path.join(x, "rlog.zst")), Path(Paths.log_root()).iterdir())
       segs = sorted(segs, key=lambda x: x.stat().st_mtime)
-      cls.lr = list(LogReader(os.path.join(segs[-1], "rlog.zst")))
-      cls.ts = msgs_to_time_series(cls.lr)
+      cls.lr = list(LogReader(os.path.join(segs[-3], "rlog.zst")))
       return
 
     # setup env
@@ -175,8 +173,7 @@ class TestOnroad:
 
     cls.lrs = [list(LogReader(os.path.join(str(s), "rlog.zst"))) for s in cls.segments]
 
-    cls.lr = cls.lrs[0]
-    cls.ts = msgs_to_time_series(cls.lr)
+    cls.lr = list(LogReader(os.path.join(str(cls.segments[0]), "rlog.zst")))
     cls.log_path = cls.segments[0]
 
     cls.log_sizes = {}
@@ -201,7 +198,7 @@ class TestOnroad:
         assert len(msgs) >= math.floor(SERVICE_LIST[s].frequency*int(TEST_DURATION*0.8))
 
   def test_manager_starting_time(self):
-    st = self.ts['managerState']['t'][0]
+    st = self.msgs['managerState'][0].logMonoTime / 1e9
     assert (st - self.manager_st) < 10, f"manager.py took {st - self.manager_st}s to publish the first 'managerState' msg"
 
   def test_cloudlog_size(self):
@@ -229,7 +226,7 @@ class TestOnroad:
     result += "-------------- UI Draw Timing ------------------\n"
     result += "------------------------------------------------\n"
 
-    ts = self.ts['uiDebug']['drawTimeMillis']
+    ts = [m.uiDebug.drawTimeMillis for m in self.msgs['uiDebug']]
     result += f"min  {min(ts):.2f}ms\n"
     result += f"max  {max(ts):.2f}ms\n"
     result += f"std  {np.std(ts):.2f}ms\n"
@@ -322,7 +319,7 @@ class TestOnroad:
     result += "-----------------  SOF Timing ------------------\n"
     result += "------------------------------------------------\n"
     for name in ['roadCameraState', 'wideRoadCameraState', 'driverCameraState']:
-      ts = self.ts[name]['timestampSof']
+      ts = [getattr(m, m.which()).timestampSof for m in self.lr if name in m.which()]
       d_ms = np.diff(ts) / 1e6
       d50 = np.abs(d_ms-50)
       result += f"{name} sof delta vs 50ms: min  {min(d50):.2f}ms\n"
@@ -341,30 +338,33 @@ class TestOnroad:
         # sanity checks within a single cam
         for cam in cams:
           with subtests.test(test="frame_skips", camera=cam):
-            assert set(np.diff(self.ts[cam]['frameId'])) == {1, }, "Frame ID skips"
+            cam_log = [getattr(x, x.which()) for x in self.msgs[cam]]
+            assert set(np.diff([x.frameId for x in cam_log])) == {1, }, "Frame ID skips"
 
             # EOF > SOF
-            eof_sof_diff = self.ts[cam]['timestampEof'] - self.ts[cam]['timestampSof']
+            eof_sof_diff = np.array([x.timestampEof - x.timestampSof for x in cam_log])
             assert np.all(eof_sof_diff > 0)
             assert np.all(eof_sof_diff < 50*1e6)
 
-        first_fid = {c: min(self.ts[c]['frameId']) for c in cams}
+        fid = {c: [getattr(m, m.which()).frameId for m in self.msgs[c]] for c in cams}
+        first_fid = [min(x) for x in fid.values()]
         if cam.endswith('CameraState'):
           # camerad guarantees that all cams start on frame ID 0
           # (note loggerd also needs to start up fast enough to catch it)
-          assert set(first_fid.values()) == {0, }, "Cameras don't start on frame ID 0"
+          assert set(first_fid) == {0, }, "Cameras don't start on frame ID 0"
         else:
           # encoder guarantees all cams start on the same frame ID
-          assert len(set(first_fid.values())) == 1, "Cameras don't start on same frame ID"
+          assert len(set(first_fid)) == 1, "Cameras don't start on same frame ID"
 
         # we don't do a full segment rotation, so these might not match exactly
-        last_fid = {c: max(self.ts[c]['frameId']) for c in cams}
-        assert max(last_fid.values()) - min(last_fid.values()) < 10
+        last_fid = [max(x) for x in fid.values()]
+        assert max(last_fid) - min(last_fid) < 10
 
-        start, end = min(first_fid.values()), min(last_fid.values())
+        start, end = min(first_fid), min(last_fid)
+        all_ts = [[getattr(m, m.which()).timestampSof for m in self.msgs[c]] for c in cams]
         for i in range(end-start):
-          ts = {c: round(self.ts[c]['timestampSof'][i]/1e6, 1) for c in cams}
-          diff = (max(ts.values()) - min(ts.values()))
+          ts = [round(x[i]/1e6, 1) for x in all_ts]
+          diff = max(ts) - min(ts)
           assert diff < 2, f"Cameras not synced properly: frame_id={start+i}, {diff=:.1f}ms, {ts=}"
 
   def test_mpc_execution_timings(self):
@@ -438,7 +438,12 @@ class TestOnroad:
 
   @release_only
   def test_startup(self):
-    startup_alert = self.ts['selfdriveState']['alertText1'][0]
+    startup_alert = None
+    for msg in self.lrs[0]:
+      # can't use onroadEvents because the first msg can be dropped while loggerd is starting up
+      if msg.which() == "selfdriveState":
+        startup_alert = msg.selfdriveState.alertText1
+        break
     expected = EVENTS[log.OnroadEvent.EventName.startup][ET.PERMANENT].alert_text_1
     assert startup_alert == expected, "wrong startup alert"