diff --git a/VECTO/OutputData/JSONFileWriter.vb b/VECTO/OutputData/JSONFileWriter.vb
index 35935860691cf18f494bf1713dabef4667dfc8dc..7d95b1e2e47f8a522ec65e7492b04fa2e155238c 100644
--- a/VECTO/OutputData/JSONFileWriter.vb
+++ b/VECTO/OutputData/JSONFileWriter.vb
@@ -207,8 +207,8 @@ Public Class JSONFileWriter
 				{"CurbWeight", vehicle.CurbMassChassis.Value()},
 				{"CurbWeightExtra", vehicle.CurbMassExtra.Value()},
 				{"Loading", vehicle.Loading.Value()},
-                		{"MassMax", vehicle.GrossVehicleMassRating.ConvertToTon()},
-		                {"rdyn", vehicle.DynamicTyreRadius.ConvertToMilliMeter()},
+           		{"MassMax", vehicle.GrossVehicleMassRating.ConvertToTon().Value},
+                {"rdyn", vehicle.DynamicTyreRadius.ConvertToMilliMeter().Value},
 				{"CdCorrMode", airdrag.CrossWindCorrectionMode.GetName()},
 				{"CdCorrFile",
 				If((airdrag.CrossWindCorrectionMode = CrossWindCorrectionMode.SpeedDependentCorrectionFactor OrElse