diff --git a/selfdrive/car/gm/interface.py b/selfdrive/car/gm/interface.py
index cead6743b..c2583ef07 100644
--- a/selfdrive/car/gm/interface.py
+++ b/selfdrive/car/gm/interface.py
@@ -141,6 +141,7 @@ class CarInterface(CarInterfaceBase):
 
     else:  # ASCM, OBD-II harness
       ret.openpilotLongitudinalControl = not frogpilot_toggles.disable_openpilot_long
+      ret.safetyConfigs[0].safetyParam |= Panda.FLAG_GM_HW_ASCM_LONG
       ret.networkLocation = NetworkLocation.gateway
       ret.radarUnavailable = RADAR_HEADER_MSG not in fingerprint[CanBus.OBSTACLE] and not docs
       ret.pcmCruise = False  # stock non-adaptive cruise control is kept off