--- a/src/aircraft_cmd.cpp
+++ b/src/aircraft_cmd.cpp
@@ -703,7 +703,7 @@
 
 static void CheckIfAircraftNeedsService(Vehicle *v)
 {
-	if (_patches.servint_aircraft == 0 || !VehicleNeedsService(v)) return;
+	if (_patches.servint_aircraft == 0 || !v->NeedsAutomaticServicing()) return;
 	if (v->IsInDepot()) {
 		VehicleServiceInDepot(v);
 		return;

--- a/src/order_cmd.cpp
+++ b/src/order_cmd.cpp
@@ -1352,7 +1352,7 @@
 			/* Let a depot order in the orderlist interrupt. */
 			if (!(v->current_order.GetDepotOrderType() & ODTFB_PART_OF_ORDERS)) return false;
 
-			if ((v->current_order.GetDepotOrderType() & ODTFB_SERVICE) && !VehicleNeedsService(v)) {
+			if ((v->current_order.GetDepotOrderType() & ODTFB_SERVICE) && !v->NeedsServicing()) {
 				UpdateVehicleTimetable(v, true);
 				v->cur_order_index++;
 			}

--- a/src/roadveh_cmd.cpp
+++ b/src/roadveh_cmd.cpp
@@ -1911,7 +1911,7 @@
 static void CheckIfRoadVehNeedsService(Vehicle *v)
 {
 	/* If we already got a slot at a stop, use that FIRST, and go to a depot later */
-	if (v->u.road.slot != NULL || _patches.servint_roadveh == 0 || !VehicleNeedsService(v)) return;
+	if (v->u.road.slot != NULL || _patches.servint_roadveh == 0 || !v->NeedsAutomaticServicing()) return;
 	if (v->IsInDepot()) {
 		VehicleServiceInDepot(v);
 		return;

--- a/src/ship_cmd.cpp
+++ b/src/ship_cmd.cpp
@@ -144,7 +144,7 @@
 
 static void CheckIfShipNeedsService(Vehicle *v)
 {
-	if (_patches.servint_ships == 0 || !VehicleNeedsService(v)) return;
+	if (_patches.servint_ships == 0 || !v->NeedsAutomaticServicing()) return;
 	if (v->IsInDepot()) {
 		VehicleServiceInDepot(v);
 		return;

--- a/src/train_cmd.cpp
+++ b/src/train_cmd.cpp
@@ -3543,7 +3543,7 @@
 {
 	static const uint MAX_ACCEPTABLE_DEPOT_DIST = 16;
 
-	if (_patches.servint_trains == 0 || !VehicleNeedsService(v)) return;
+	if (_patches.servint_trains == 0 || !v->NeedsAutomaticServicing()) return;
 	if (v->IsInDepot()) {
 		VehicleServiceInDepot(v);
 		return;

--- a/src/vehicle.cpp
+++ b/src/vehicle.cpp
@@ -118,22 +118,27 @@
 	InvalidateWindow(WC_VEHICLE_DETAILS, v->index); // ensure that last service date and reliability are updated
 }
 
-bool VehicleNeedsService(const Vehicle *v)
+bool Vehicle::NeedsServicing() const
 {
-	if (v->vehstatus & (VS_STOPPED | VS_CRASHED))       return false;
-	if (!v->current_order.IsType(OT_GOTO_DEPOT) || !(v->current_order.GetDepotOrderType() & ODTFB_PART_OF_ORDERS)) { // Don't interfere with a depot visit by the order list
-		if (_patches.gotodepot && VehicleHasDepotOrders(v)) return false;
-		if (v->current_order.IsType(OT_LOADING))            return false;
-		if (v->current_order.IsType(OT_GOTO_DEPOT) && v->current_order.GetDepotActionType() & ODATFB_HALT) return false;
-	}
+	if (this->vehstatus & (VS_STOPPED | VS_CRASHED)) return false;
 
 	if (_patches.no_servicing_if_no_breakdowns && _opt.diff.vehicle_breakdowns == 0) {
-		return EngineHasReplacementForPlayer(GetPlayer(v->owner), v->engine_type, v->group_id);  /* Vehicles set for autoreplacing needs to go to a depot even if breakdowns are turned off */
+		/* Vehicles set for autoreplacing needs to go to a depot even if breakdowns are turned off.
+		 * Note: If servicing is enabled, we postpone replacement till next service. */
+		return EngineHasReplacementForPlayer(GetPlayer(this->owner), this->engine_type, this->group_id);
 	}
 
 	return _patches.servint_ispercent ?
-		(v->reliability < GetEngine(v->engine_type)->reliability * (100 - v->service_interval) / 100) :
-		(v->date_of_last_service + v->service_interval < _date);
+		(this->reliability < GetEngine(this->engine_type)->reliability * (100 - this->service_interval) / 100) :
+		(this->date_of_last_service + this->service_interval < _date);
+}
+
+bool Vehicle::NeedsAutomaticServicing() const
+{
+	if (_patches.gotodepot && VehicleHasDepotOrders(this)) return false;
+	if (this->current_order.IsType(OT_LOADING))            return false;
+	if (this->current_order.IsType(OT_GOTO_DEPOT) && this->current_order.GetDepotActionType() & ODATFB_HALT) return false;
+	return NeedsServicing();
 }
 
 StringID VehicleInTheWayErrMsg(const Vehicle* v)

--- a/src/vehicle_base.h
+++ b/src/vehicle_base.h
@@ -490,6 +490,21 @@
 	bool NeedsAutorenewing(const Player *p) const;
 
 	/**
+	 * Check if the vehicle needs to go to a depot in near future (if a opportunity presents itself) for service or replacement.
+	 *
+	 * @see NeedsAutomaticServicing()
+	 * @return true if the vehicle should go to a depot if a opportunity presents itself.
+	 */
+	bool NeedsServicing() const;
+
+	/**
+	 * Checks if the current order should be interupted for a service-in-depot-order.
+	 * @see NeedsServicing()
+	 * @return true if the current order should be interupted.
+	 */
+	bool NeedsAutomaticServicing() const;
+
+	/**
 	 * Determine the location for the station where the vehicle goes to next.
 	 * Things done for example are allocating slots in a road stop or exact
 	 * location of the platform is determined for ships.

--- a/src/vehicle_func.h
+++ b/src/vehicle_func.h
@@ -66,8 +66,6 @@
 void TrainPowerChanged(Vehicle *v);
 Money GetTrainRunningCost(const Vehicle *v);
 
-bool VehicleNeedsService(const Vehicle *v);
-
 uint GenerateVehicleSortList(const Vehicle*** sort_list, uint16 *length_of_array, VehicleType type, PlayerID owner, uint32 index, uint16 window_type);
 void BuildDepotVehicleList(VehicleType type, TileIndex tile, Vehicle ***engine_list, uint16 *engine_list_length, uint16 *engine_count, Vehicle ***wagon_list, uint16 *wagon_list_length, uint16 *wagon_count);
 CommandCost SendAllVehiclesToDepot(VehicleType type, uint32 flags, bool service, PlayerID owner, uint16 vlw_flag, uint32 id);