diff --git a/mjx/mujoco/mjx/_src/io.py b/mjx/mujoco/mjx/_src/io.py
index 0988e25c..dad0b573 100644
--- a/mjx/mujoco/mjx/_src/io.py
+++ b/mjx/mujoco/mjx/_src/io.py
@@ -233,9 +233,11 @@ def make_data(
         solreffriction=jp.zeros((ncon, mujoco.mjNREF), dtype=float),
         solimp=jp.zeros((ncon, mujoco.mjNIMP), dtype=float),
         dim=dim,
-        geom1=jp.full((ncon,), -1, dtype=jp.int32),
-        geom2=jp.full((ncon,), -1, dtype=jp.int32),
-        geom=jp.full((ncon, 2), -1, dtype=jp.int32),
+        # let jax pick contact.geom int precision, for interop with
+        # jax_enable_x64
+        geom1=jp.full((ncon,), -1, dtype=int),
+        geom2=jp.full((ncon,), -1, dtype=int),
+        geom=jp.full((ncon, 2), -1, dtype=int),
         efc_address=efc_address,
     )