diff --git a/goldens/size-tracking/integration-payloads.json b/goldens/size-tracking/integration-payloads.json
index a9421ae7dc..a0232300df 100644
--- a/goldens/size-tracking/integration-payloads.json
+++ b/goldens/size-tracking/integration-payloads.json
@@ -39,7 +39,7 @@
     "master": {
       "uncompressed": {
         "runtime-es2015": 2289,
-        "main-es2015": 245303,
+        "main-es2015": 242351,
         "polyfills-es2015": 36938,
         "5-es2015": 751
       }
@@ -49,7 +49,7 @@
     "master": {
       "uncompressed": {
         "runtime-es2015": 2289,
-        "main-es2015": 221887,
+        "main-es2015": 218961,
         "polyfills-es2015": 36723,
         "5-es2015": 781
       }
diff --git a/packages/router/src/directives/router_link.ts b/packages/router/src/directives/router_link.ts
index 1bc801df4b..96c35d87e0 100644
--- a/packages/router/src/directives/router_link.ts
+++ b/packages/router/src/directives/router_link.ts
@@ -7,7 +7,7 @@
  */
 
 import {LocationStrategy} from '@angular/common';
-import {Attribute, Directive, ElementRef, HostBinding, HostListener, Input, isDevMode, OnChanges, OnDestroy, Renderer2, SimpleChanges} from '@angular/core';
+import {Attribute, Directive, ElementRef, HostBinding, HostListener, Input, OnChanges, OnDestroy, Renderer2, SimpleChanges} from '@angular/core';
 import {Subject, Subscription} from 'rxjs';
 
 import {QueryParamsHandling} from '../config';
@@ -206,7 +206,7 @@ export class RouterLink implements OnChanges {
    */
   @Input()
   set preserveQueryParams(value: boolean) {
-    if (isDevMode() && <any>console && <any>console.warn) {
+    if ((typeof ngDevMode === 'undefined' || ngDevMode) && <any>console && <any>console.warn) {
       console.warn('preserveQueryParams is deprecated!, use queryParamsHandling instead.');
     }
     this.preserve = value;
@@ -342,7 +342,7 @@ export class RouterLinkWithHref implements OnChanges, OnDestroy {
    */
   @Input()
   set preserveQueryParams(value: boolean) {
-    if (isDevMode() && <any>console && <any>console.warn) {
+    if ((typeof ngDevMode === 'undefined' || ngDevMode) && <any>console && <any>console.warn) {
       console.warn('preserveQueryParams is deprecated, use queryParamsHandling instead.');
     }
     this.preserve = value;
diff --git a/packages/router/src/operators/activate_routes.ts b/packages/router/src/operators/activate_routes.ts
index d946feaa7b..2de203ea4a 100644
--- a/packages/router/src/operators/activate_routes.ts
+++ b/packages/router/src/operators/activate_routes.ts
@@ -6,7 +6,6 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {isDevMode} from '@angular/core';
 import {MonoTypeOperatorFunction} from 'rxjs';
 import {map} from 'rxjs/operators';
 
@@ -186,7 +185,7 @@ export class ActivateRoutes {
             // Activate the outlet when it has already been instantiated
             // Otherwise it will get activated from its `ngOnInit` when instantiated
             context.outlet.activateWith(future, cmpFactoryResolver);
-          } else if (isDevMode() && console && console.warn) {
+          } else if ((typeof ngDevMode === 'undefined' || ngDevMode) && console && console.warn) {
             console.warn(
                 `A router outlet has not been instantiated during routes activation. URL Segment: '${
                     future.snapshot._urlSegment}'`);
diff --git a/packages/router/src/router.ts b/packages/router/src/router.ts
index d8bc23fd30..b1f1f744cb 100644
--- a/packages/router/src/router.ts
+++ b/packages/router/src/router.ts
@@ -7,7 +7,7 @@
  */
 
 import {Location, PopStateEvent} from '@angular/common';
-import {Compiler, Injectable, Injector, isDevMode, NgModuleFactoryLoader, NgModuleRef, NgZone, Type, ɵConsole as Console} from '@angular/core';
+import {Compiler, Injectable, Injector, NgModuleFactoryLoader, NgModuleRef, NgZone, Type, ɵConsole as Console} from '@angular/core';
 import {BehaviorSubject, EMPTY, Observable, of, Subject, SubscriptionLike} from 'rxjs';
 import {catchError, filter, finalize, map, switchMap, tap} from 'rxjs/operators';
 
@@ -1077,7 +1077,8 @@ export class Router {
       queryParamsHandling,
       preserveFragment
     } = navigationExtras;
-    if (isDevMode() && preserveQueryParams && <any>console && <any>console.warn) {
+    if ((typeof ngDevMode === 'undefined' || ngDevMode) && preserveQueryParams && <any>console &&
+        <any>console.warn) {
       console.warn('preserveQueryParams is deprecated, use queryParamsHandling instead.');
     }
     const a = relativeTo || this.routerState.root;
@@ -1131,7 +1132,8 @@ export class Router {
    */
   navigateByUrl(url: string|UrlTree, extras: NavigationExtras = {skipLocationChange: false}):
       Promise<boolean> {
-    if (isDevMode() && this.isNgZoneEnabled && !NgZone.isInAngularZone()) {
+    if (typeof ngDevMode === 'undefined' ||
+        ngDevMode && this.isNgZoneEnabled && !NgZone.isInAngularZone()) {
       this.console.warn(
           `Navigation triggered outside Angular zone, did you forget to call 'ngZone.run()'?`);
     }
diff --git a/packages/router/src/router_module.ts b/packages/router/src/router_module.ts
index d23731ca89..a9eda6529f 100644
--- a/packages/router/src/router_module.ts
+++ b/packages/router/src/router_module.ts
@@ -188,7 +188,7 @@ export function provideLocationStrategy(
 }
 
 export function provideForRootGuard(router: Router): any {
-  if (router) {
+  if ((typeof ngDevMode === 'undefined' || ngDevMode) && router) {
     throw new Error(
         `RouterModule.forRoot() called twice. Lazy loaded modules should use RouterModule.forChild() instead.`);
   }
diff --git a/packages/router/src/utils/config.ts b/packages/router/src/utils/config.ts
index f38e56cfd4..f8f53c6cc6 100644
--- a/packages/router/src/utils/config.ts
+++ b/packages/router/src/utils/config.ts
@@ -20,8 +20,9 @@ export function validateConfig(config: Routes, parentPath: string = ''): void {
 }
 
 function validateNode(route: Route, fullPath: string): void {
-  if (!route) {
-    throw new Error(`
+  if (typeof ngDevMode === 'undefined' || ngDevMode) {
+    if (!route) {
+      throw new Error(`
       Invalid configuration of route '${fullPath}': Encountered undefined route.
       The reason might be an extra comma.
 
@@ -32,55 +33,57 @@ function validateNode(route: Route, fullPath: string): void {
         { path: 'detail/:id', component: HeroDetailComponent }
       ];
     `);
-  }
-  if (Array.isArray(route)) {
-    throw new Error(`Invalid configuration of route '${fullPath}': Array cannot be specified`);
-  }
-  if (!route.component && !route.children && !route.loadChildren &&
-      (route.outlet && route.outlet !== PRIMARY_OUTLET)) {
-    throw new Error(`Invalid configuration of route '${
-        fullPath}': a componentless route without children or loadChildren cannot have a named outlet set`);
-  }
-  if (route.redirectTo && route.children) {
-    throw new Error(`Invalid configuration of route '${
-        fullPath}': redirectTo and children cannot be used together`);
-  }
-  if (route.redirectTo && route.loadChildren) {
-    throw new Error(`Invalid configuration of route '${
-        fullPath}': redirectTo and loadChildren cannot be used together`);
-  }
-  if (route.children && route.loadChildren) {
-    throw new Error(`Invalid configuration of route '${
-        fullPath}': children and loadChildren cannot be used together`);
-  }
-  if (route.redirectTo && route.component) {
-    throw new Error(`Invalid configuration of route '${
-        fullPath}': redirectTo and component cannot be used together`);
-  }
-  if (route.path && route.matcher) {
-    throw new Error(
-        `Invalid configuration of route '${fullPath}': path and matcher cannot be used together`);
-  }
-  if (route.redirectTo === void 0 && !route.component && !route.children && !route.loadChildren) {
-    throw new Error(`Invalid configuration of route '${
-        fullPath}'. One of the following must be provided: component, redirectTo, children or loadChildren`);
-  }
-  if (route.path === void 0 && route.matcher === void 0) {
-    throw new Error(`Invalid configuration of route '${
-        fullPath}': routes must have either a path or a matcher specified`);
-  }
-  if (typeof route.path === 'string' && route.path.charAt(0) === '/') {
-    throw new Error(`Invalid configuration of route '${fullPath}': path cannot start with a slash`);
-  }
-  if (route.path === '' && route.redirectTo !== void 0 && route.pathMatch === void 0) {
-    const exp =
-        `The default value of 'pathMatch' is 'prefix', but often the intent is to use 'full'.`;
-    throw new Error(`Invalid configuration of route '{path: "${fullPath}", redirectTo: "${
-        route.redirectTo}"}': please provide 'pathMatch'. ${exp}`);
-  }
-  if (route.pathMatch !== void 0 && route.pathMatch !== 'full' && route.pathMatch !== 'prefix') {
-    throw new Error(`Invalid configuration of route '${
-        fullPath}': pathMatch can only be set to 'prefix' or 'full'`);
+    }
+    if (Array.isArray(route)) {
+      throw new Error(`Invalid configuration of route '${fullPath}': Array cannot be specified`);
+    }
+    if (!route.component && !route.children && !route.loadChildren &&
+        (route.outlet && route.outlet !== PRIMARY_OUTLET)) {
+      throw new Error(`Invalid configuration of route '${
+          fullPath}': a componentless route without children or loadChildren cannot have a named outlet set`);
+    }
+    if (route.redirectTo && route.children) {
+      throw new Error(`Invalid configuration of route '${
+          fullPath}': redirectTo and children cannot be used together`);
+    }
+    if (route.redirectTo && route.loadChildren) {
+      throw new Error(`Invalid configuration of route '${
+          fullPath}': redirectTo and loadChildren cannot be used together`);
+    }
+    if (route.children && route.loadChildren) {
+      throw new Error(`Invalid configuration of route '${
+          fullPath}': children and loadChildren cannot be used together`);
+    }
+    if (route.redirectTo && route.component) {
+      throw new Error(`Invalid configuration of route '${
+          fullPath}': redirectTo and component cannot be used together`);
+    }
+    if (route.path && route.matcher) {
+      throw new Error(
+          `Invalid configuration of route '${fullPath}': path and matcher cannot be used together`);
+    }
+    if (route.redirectTo === void 0 && !route.component && !route.children && !route.loadChildren) {
+      throw new Error(`Invalid configuration of route '${
+          fullPath}'. One of the following must be provided: component, redirectTo, children or loadChildren`);
+    }
+    if (route.path === void 0 && route.matcher === void 0) {
+      throw new Error(`Invalid configuration of route '${
+          fullPath}': routes must have either a path or a matcher specified`);
+    }
+    if (typeof route.path === 'string' && route.path.charAt(0) === '/') {
+      throw new Error(
+          `Invalid configuration of route '${fullPath}': path cannot start with a slash`);
+    }
+    if (route.path === '' && route.redirectTo !== void 0 && route.pathMatch === void 0) {
+      const exp =
+          `The default value of 'pathMatch' is 'prefix', but often the intent is to use 'full'.`;
+      throw new Error(`Invalid configuration of route '{path: "${fullPath}", redirectTo: "${
+          route.redirectTo}"}': please provide 'pathMatch'. ${exp}`);
+    }
+    if (route.pathMatch !== void 0 && route.pathMatch !== 'full' && route.pathMatch !== 'prefix') {
+      throw new Error(`Invalid configuration of route '${
+          fullPath}': pathMatch can only be set to 'prefix' or 'full'`);
+    }
   }
   if (route.children) {
     validateConfig(route.children, fullPath);