diff --git a/Nasal/payload.nas b/Nasal/payload.nas
index 5572dd2f..a392164b 100644
--- a/Nasal/payload.nas
+++ b/Nasal/payload.nas
@@ -12,11 +12,11 @@ var fuelSvc = {
 	
 	newRequest: func() {
 		if (pts.Sim.aero.getValue() == "A320-200-CFM") {
-			me.Nodes.requestTotalLbs.setValue(math.min(pts.Consumables.Fuel.totalFuelLbs.getValue() + me.Nodes.requestLbs.getValue(), 42872));
+			me.Nodes.requestTotalLbs.setValue(math.max(math.min(pts.Consumables.Fuel.totalFuelLbs.getValue() + me.Nodes.requestLbs.getValue(), 42872), 0));
 		} elsif (pts.Sim.aero.getValue() == "A320-200-IAE" or pts.Sim.aero.getValue() == "A320-100-CFM") {
-			me.Nodes.requestTotalLbs.setValue(math.min(pts.Consumables.Fuel.totalFuelLbs.getValue() + me.Nodes.requestLbs.getValue(), 42214));
+			me.Nodes.requestTotalLbs.setValue(math.max(math.min(pts.Consumables.Fuel.totalFuelLbs.getValue() + me.Nodes.requestLbs.getValue(), 42214), 0));
 		} elsif (pts.Sim.aero.getValue() == "A320neo-CFM" or pts.Sim.aero.getValue() == "A320neo-PW") {
-			me.Nodes.requestTotalLbs.setValue(math.min(pts.Consumables.Fuel.totalFuelLbs.getValue() + me.Nodes.requestLbs.getValue(), 41977));
+			me.Nodes.requestTotalLbs.setValue(math.max(math.min(pts.Consumables.Fuel.totalFuelLbs.getValue() + me.Nodes.requestLbs.getValue(), 41977), 0));
 		}
 	},
 	
diff --git a/Systems/a320-fuel.xml b/Systems/a320-fuel.xml
index ae1e934c..5af3f62b 100644
--- a/Systems/a320-fuel.xml
+++ b/Systems/a320-fuel.xml
@@ -414,6 +414,13 @@
 				/systems/fuel/pumps/wing-pump-left-1-operate eq 1
 				/systems/fuel/pumps/wing-pump-left-2-operate eq 1
 			</test>
+			<test logic="AND" value="0"> <!-- crossfeeding overrides gravity feed -->
+				/systems/fuel/valves/crossfeed-valve eq 1
+				<test logic="OR">
+					/systems/fuel/pumps/wing-pump-right-1-operate eq 1
+					/systems/fuel/pumps/wing-pump-right-2-operate eq 1
+				</test>
+			</test>
 			<test logic="AND" value="1"> <!-- Suction/Gravity feed if G is not to far below 1 -->
 				/accelerations/pilot-gdamped ge 0.5
 			</test>
@@ -425,6 +432,13 @@
 				/systems/fuel/pumps/wing-pump-right-1-operate eq 1
 				/systems/fuel/pumps/wing-pump-right-2-operate eq 1
 			</test>
+			<test logic="AND" value="0"> <!-- crossfeeding overrides gravity feed -->
+				/systems/fuel/valves/crossfeed-valve eq 1
+				<test logic="OR">
+					/systems/fuel/pumps/wing-pump-left-1-operate eq 1
+					/systems/fuel/pumps/wing-pump-left-2-operate eq 1
+				</test>
+			</test>
 			<test logic="AND" value="1"> <!-- Suction/Gravity feed if G is not to far below 1 -->
 				/accelerations/pilot-gdamped ge 0.5
 			</test>