diff --git a/ACKReactiveExtensions.podspec b/ACKReactiveExtensions.podspec
index 8a5ef75..0e16c96 100644
--- a/ACKReactiveExtensions.podspec
+++ b/ACKReactiveExtensions.podspec
@@ -49,7 +49,7 @@ Pod::Spec.new do |s|
 
   s.subspec 'SDWebImage' do |sdwebimage|
     sdwebimage.dependency 'ACKReactiveExtensions/Core'
-    sdwebimage.dependency 'SDWebImage'
+    sdwebimage.dependency 'SDWebImage', '~> 4.0'
     sdwebimage.source_files = 'ACKReactiveExtensions/SDWebImage/**/*'
   end
 
diff --git a/ACKReactiveExtensions/SDWebImage/SDWebImage+RAC.swift b/ACKReactiveExtensions/SDWebImage/SDWebImage+RAC.swift
index 64f9d5c..9a4ca30 100644
--- a/ACKReactiveExtensions/SDWebImage/SDWebImage+RAC.swift
+++ b/ACKReactiveExtensions/SDWebImage/SDWebImage+RAC.swift
@@ -22,7 +22,9 @@ extension Reactive where Base: SDWebImageDownloader {
                 sink.sendCompleted()
             }
             disposable.add({
-                task?.cancel()
+                if let token = task?.downloadOperationCancelToken as? SDWebImageDownloadToken {
+                    self.base.cancel(token)
+                }
             })
         }
     }
@@ -55,7 +57,9 @@ extension SDWebImageDownloader {
                 sink.sendCompleted()
             }
             disposable.add({ 
-                task?.cancel()
+                if let token = task?.downloadOperationCancelToken as? SDWebImageDownloadToken {
+                    self.cancel(token)
+                }
             })
         }
     }
diff --git a/Example/Podfile.lock b/Example/Podfile.lock
index 92dc759..b1f10c5 100644
--- a/Example/Podfile.lock
+++ b/Example/Podfile.lock
@@ -1,39 +1,39 @@
 PODS:
-  - ACKReactiveExtensions (2.2.2):
-    - ACKReactiveExtensions/Core (= 2.2.2)
-    - ACKReactiveExtensions/UIKit (= 2.2.2)
-    - ReactiveCocoa (~> 5.0.0-rc.1)
-  - ACKReactiveExtensions/Argo (2.2.2):
+  - ACKReactiveExtensions (2.3.0):
+    - ACKReactiveExtensions/Core (= 2.3.0)
+    - ACKReactiveExtensions/UIKit (= 2.3.0)
+    - ReactiveCocoa (~> 5.0)
+  - ACKReactiveExtensions/Argo (2.3.0):
     - Argo (~> 4.0)
-    - ReactiveCocoa (~> 5.0.0-rc.1)
-  - ACKReactiveExtensions/Core (2.2.2):
-    - ReactiveCocoa (~> 5.0.0-rc.1)
-  - ACKReactiveExtensions/Reachability (2.2.2):
+    - ReactiveCocoa (~> 5.0)
+  - ACKReactiveExtensions/Core (2.3.0):
+    - ReactiveCocoa (~> 5.0)
+  - ACKReactiveExtensions/Reachability (2.3.0):
     - ACKReactiveExtensions/Core
     - Reachability
-    - ReactiveCocoa (~> 5.0.0-rc.1)
-  - ACKReactiveExtensions/Realm (2.2.2):
+    - ReactiveCocoa (~> 5.0)
+  - ACKReactiveExtensions/Realm (2.3.0):
     - ACKReactiveExtensions/Core
-    - ReactiveCocoa (~> 5.0.0-rc.1)
+    - ReactiveCocoa (~> 5.0)
     - RealmSwift (~> 2.1)
-  - ACKReactiveExtensions/SDWebImage (2.2.2):
+  - ACKReactiveExtensions/SDWebImage (2.3.0):
     - ACKReactiveExtensions/Core
-    - ReactiveCocoa (~> 5.0.0-rc.1)
+    - ReactiveCocoa (~> 5.0)
     - SDWebImage
-  - ACKReactiveExtensions/UIKit (2.2.2):
+  - ACKReactiveExtensions/UIKit (2.3.0):
     - ACKReactiveExtensions/Core
-    - ReactiveCocoa (~> 5.0.0-rc.1)
-  - ACKReactiveExtensions/WebKit (2.2.2):
+    - ReactiveCocoa (~> 5.0)
+  - ACKReactiveExtensions/WebKit (2.3.0):
     - ACKReactiveExtensions/Core
-    - ReactiveCocoa (~> 5.0.0-rc.1)
+    - ReactiveCocoa (~> 5.0)
   - Argo (4.1.1):
     - Runes (>= 4.0.0)
   - Nimble (5.1.1)
   - Quick (0.10.0)
   - Reachability (3.2)
-  - ReactiveCocoa (5.0.0-rc.1):
-    - ReactiveSwift (~> 1.0.0-rc.3)
-  - ReactiveSwift (1.0.0):
+  - ReactiveCocoa (5.0.1):
+    - ReactiveSwift (~> 1.1)
+  - ReactiveSwift (1.1.0):
     - Result (~> 3.1)
   - Realm (2.1.2):
     - Realm/Headers (= 2.1.2)
@@ -42,9 +42,9 @@ PODS:
     - Realm (= 2.1.2)
   - Result (3.1.0)
   - Runes (4.0.1)
-  - SDWebImage (3.8.2):
-    - SDWebImage/Core (= 3.8.2)
-  - SDWebImage/Core (3.8.2)
+  - SDWebImage (4.0.0):
+    - SDWebImage/Core (= 4.0.0)
+  - SDWebImage/Core (4.0.0)
 
 DEPENDENCIES:
   - ACKReactiveExtensions (from `../`)
@@ -59,22 +59,22 @@ DEPENDENCIES:
 
 EXTERNAL SOURCES:
   ACKReactiveExtensions:
-    :path: ../
+    :path: "../"
 
 SPEC CHECKSUMS:
-  ACKReactiveExtensions: c9b0a363ba76fe47dfdb074fb7da40ef988f0bf7
+  ACKReactiveExtensions: 19813af5a953c3d48f6aa553c28350e5730d52c5
   Argo: 014ac072f97462bc1a9b83d302edb351488a532f
   Nimble: 415e3aa3267e7bc2c96b05fa814ddea7bb686a29
   Quick: 5d290df1c69d5ee2f0729956dcf0fd9a30447eaa
   Reachability: 33e18b67625424e47b6cde6d202dce689ad7af96
-  ReactiveCocoa: 3e9cad4b77fa199d41e03f603cb55d0701ad6ad8
-  ReactiveSwift: f391724ee318a2cfd3e37dfb041cd49ecf4e7869
+  ReactiveCocoa: f577006aa6c7b0b08020109ebaae3b77ada00adc
+  ReactiveSwift: 2f4e4a02e5a5c87ea63f5fe667163ce2a67cbb57
   Realm: efe855f4d977c8ce5a82d3116d9f1ff155a6550c
   RealmSwift: 17d6ee30b6f9df86364408c2197492e33bfea567
   Result: 4e3ed5995ed94d0cd6a09be9a431fce3f3624bbf
   Runes: ff20f163b478ac2c0e18158d6086fd5b1997f983
-  SDWebImage: 098e97e6176540799c27e804c96653ee0833d13c
+  SDWebImage: 76a6348bdc74eb5a55dd08a091ef298e56b55e41
 
 PODFILE CHECKSUM: 1ed247216cfa78d69af7c9aed3f2ed92db7fcd17
 
-COCOAPODS: 1.2.0.rc.1
+COCOAPODS: 1.2.0