diff --git a/VECTO/GUI/GearboxForm.vb b/VECTO/GUI/GearboxForm.vb
index 2353480e692b74a97bc4662ee686ee0def09890e..c1a30f50dc1e9c01a17ade1c32cd76f70f9c704c 100644
--- a/VECTO/GUI/GearboxForm.vb
+++ b/VECTO/GUI/GearboxForm.vb
@@ -911,8 +911,9 @@ Public Class GearboxForm
 			If (vehicle.Axles.Count < 2) Then
 				Return Nothing
 			End If
-             'TODO: 
-			rDyn = DeclarationData.Wheels.Lookup(vehicle.Axles(1).Tyre.Dimension).DynamicTyreRadius
+            rdyn = vehicle.Axles.Where(Function(axle)  axle.AxleType = AxleType.VehicleDriven) _
+                .Select(Function(da) DeclarationData.Wheels.Lookup(da.Tyre.Dimension).DynamicTyreRadius) _
+		        .Average()
 		End If
 		If (rDyn.IsEqual(0)) Then
 			Return Nothing