diff --git a/iris_grib/_save_rules.py b/iris_grib/_save_rules.py
index 63b592fa..9b9b467d 100644
--- a/iris_grib/_save_rules.py
+++ b/iris_grib/_save_rules.py
@@ -1059,7 +1059,7 @@ def product_definition_template_1(cube, grib, full3d_cube=None):
 
     """
     gribapi.grib_set(grib, "productDefinitionTemplateNumber", 1)
-    product_definition_template_common(cube, grib)
+    product_definition_template_common(cube, grib, full3d_cube)
     set_ensemble(cube, grib)
 
 
diff --git a/iris_grib/tests/integration/round_trip/__init__.py b/iris_grib/tests/integration/round_trip/__init__.py
new file mode 100644
index 00000000..bcf17a3d
--- /dev/null
+++ b/iris_grib/tests/integration/round_trip/__init__.py
@@ -0,0 +1,21 @@
+# (C) British Crown Copyright 2018, Met Office
+#
+# This file is part of iris-grib.
+#
+# iris-grib is free software: you can redistribute it and/or modify it under
+# the terms of the GNU Lesser General Public License as published by the
+# Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# iris-grib is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with iris-grib.  If not, see <http://www.gnu.org/licenses/>.
+"""Integration tests for the :mod:`iris_grib._load_convert` and
+:mod:`iris_grib._save_rules` packages."""
+
+from __future__ import (absolute_import, division, print_function)
+from six.moves import (filter, input, map, range, zip)  # noqa
diff --git a/iris_grib/tests/integration/round_trip/test_hybrid_coords_round_trip.py b/iris_grib/tests/integration/round_trip/test_hybrid_coords_round_trip.py
new file mode 100644
index 00000000..e64df0bd
--- /dev/null
+++ b/iris_grib/tests/integration/round_trip/test_hybrid_coords_round_trip.py
@@ -0,0 +1,74 @@
+# (C) British Crown Copyright 2018, Met Office
+#
+# This file is part of iris-grib.
+#
+# iris-grib is free software: you can redistribute it and/or modify it under
+# the terms of the GNU Lesser General Public License as published by the
+# Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# iris-grib is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with iris-grib.  If not, see <http://www.gnu.org/licenses/>.
+"""
+Integration test for round-trip loading and saving of hybrid height and
+hybrid pressure cubes.
+
+"""
+
+from __future__ import (absolute_import, division, print_function)
+from six.moves import (filter, input, map, range, zip)  # noqa
+
+# import iris_grib.tests first so that some things can be initialised
+# before importing anything else.
+import iris_grib.tests as tests
+
+import os
+
+from iris import load_cube, load_cubes, save
+from iris.experimental.equalise_cubes import equalise_attributes
+
+
+class TestHybridHeightRoundTrip(tests.IrisGribTest):
+    def test_hh_round_trip(self):
+        filepath = self.get_testdata_path(
+            'faked_sample_hh_grib_data.grib2')
+        # Load and save temperature cube and reference (orography) cube
+        # separately because this is the only way to save the hybrid height
+        # coordinate.
+        cube, ref_cube = load_cubes(filepath,
+                                    ('air_temperature', 'surface_altitude'))
+
+        with self.temp_filename() as tmp_save_path:
+            save([cube, ref_cube], tmp_save_path, saver='grib2')
+            # Only need to reload temperature cube to compare with unsaved
+            # temperature cube.
+            saved_cube = load_cube(tmp_save_path, 'air_temperature')
+            self.assertTrue(saved_cube == cube)
+
+
+class TestHybridPressureRoundTrip(tests.IrisGribTest):
+    def test_hybrid_pressure(self):
+        filepath = self.get_testdata_path(
+            'faked_sample_hp_grib_data.grib2')
+        # Load and save temperature cube and reference (air_pressure at
+        # surface) cube separately because this is the only way to save the
+        # hybrid pressure coordinate.
+        cube, ref_cube = load_cubes(filepath,
+                                    ('air_temperature', 'air_pressure'))
+
+        with self.temp_filename() as tmp_save_path:
+            save([cube, ref_cube], tmp_save_path, saver='grib2')
+            # Only need to reload temperature cube to compare with unsaved
+            # temperature cube.
+            saved_cube = load_cube(tmp_save_path, 'air_temperature')
+
+            # Currently all attributes are lost when saving to grib, so we must
+            # equalise them in order to successfully compare all other aspects.
+            equalise_attributes([saved_cube, cube])
+
+            self.assertTrue(saved_cube == cube)