diff --git a/board/safety/safety_gm.h b/board/safety/safety_gm.h
index 4fd65b38c014ba..e70332c1ebc9fa 100644
--- a/board/safety/safety_gm.h
+++ b/board/safety/safety_gm.h
@@ -17,7 +17,7 @@ const int GM_DRIVER_TORQUE_ALLOWANCE = 50;
 const int GM_DRIVER_TORQUE_FACTOR = 4;
 const int GM_MAX_GAS = 3072;
 const int GM_MAX_REGEN = 1404;
-const int GM_MAX_BRAKE = 255;
+const int GM_MAX_BRAKE = 350;
 
 int gm_brake_prev = 0;
 int gm_gas_prev = 0;
diff --git a/tests/safety/test_gm.py b/tests/safety/test_gm.py
index 8efba5e3183ecc..f11360dbe2a3fb 100644
--- a/tests/safety/test_gm.py
+++ b/tests/safety/test_gm.py
@@ -6,7 +6,7 @@
 MAX_RATE_UP = 7
 MAX_RATE_DOWN = 17
 MAX_STEER = 255
-MAX_BRAKE = 255
+MAX_BRAKE = 350
 MAX_GAS = 3072
 MAX_REGEN = 1404