diff --git a/actionpack/lib/action_dispatch/journey/formatter.rb b/actionpack/lib/action_dispatch/journey/formatter.rb
index 7d1f5ab7c9d1d5da26fe2579533e77f00ebdb3b3..ca47b94c7e77509ddf84773fe0cd4ad227455fc8 100644
--- a/actionpack/lib/action_dispatch/journey/formatter.rb
+++ b/actionpack/lib/action_dispatch/journey/formatter.rb
@@ -15,12 +15,12 @@ def initialize(routes)
         @cache  = nil
       end
 
-      def generate(name, options, path_parameters, parameterize = nil)
+      def generate(name, options, path_parameters)
         constraints = path_parameters.merge(options)
         missing_keys = nil
 
         match_route(name, constraints) do |route|
-          parameterized_parts = extract_parameterized_parts(route, options, path_parameters, parameterize)
+          parameterized_parts = extract_parameterized_parts(route, options, path_parameters)
 
           # Skip this route unless a name has been provided or it is a
           # standard Rails route since we can't determine whether an options
@@ -62,7 +62,7 @@ def clear
       end
 
       private
-        def extract_parameterized_parts(route, options, recall, parameterize = nil)
+        def extract_parameterized_parts(route, options, recall)
           parameterized_parts = recall.merge(options)
 
           keys_to_keep = route.parts.reverse_each.drop_while { |part|
@@ -73,9 +73,11 @@ def extract_parameterized_parts(route, options, recall, parameterize = nil)
             !keys_to_keep.include?(bad_key)
           end
 
-          if parameterize
-            parameterized_parts.each do |k, v|
-              parameterized_parts[k] = parameterize.call(k, v)
+          parameterized_parts.each do |k, v|
+            if k == :controller
+              parameterized_parts[k] = v
+            else
+              parameterized_parts[k] = v.to_param
             end
           end
 
diff --git a/actionpack/lib/action_dispatch/routing/route_set.rb b/actionpack/lib/action_dispatch/routing/route_set.rb
index 9b1162998f5bafee154b013add8d81a91d35f808..e7773d80d384337c74ba61ca70d8ccb5bda35449 100644
--- a/actionpack/lib/action_dispatch/routing/route_set.rb
+++ b/actionpack/lib/action_dispatch/routing/route_set.rb
@@ -650,14 +650,6 @@ def merge_defaults(options)
       end
 
       class Generator
-        PARAMETERIZE = lambda do |name, value|
-          if name == :controller
-            value
-          else
-            value.to_param
-          end
-        end
-
         attr_reader :options, :recall, :set, :named_route
 
         def initialize(named_route, options, recall, set)
@@ -744,7 +736,7 @@ def normalize_controller!
         # Generates a path from routes, returns [path, params].
         # If no route is generated the formatter will raise ActionController::UrlGenerationError
         def generate
-          @set.formatter.generate(named_route, options, recall, PARAMETERIZE)
+          @set.formatter.generate(named_route, options, recall)
         end
 
         def different_controller?
diff --git a/actionpack/test/journey/router_test.rb b/actionpack/test/journey/router_test.rb
index fe0e3a975b0aeb5a9e82fd481e515dd266c7da5d..4e7374a7d4599669e478e318c49b29918c4e225b 100644
--- a/actionpack/test/journey/router_test.rb
+++ b/actionpack/test/journey/router_test.rb
@@ -224,22 +224,6 @@ def test_generate_slash
         assert_equal "/", path
       end
 
-      def test_generate_calls_param_proc
-        get "/:controller(/:action)", to: "foo#bar"
-
-        parameterized = []
-        params = [ [:controller, "tasks"],
-                   [:action, "show"] ]
-
-        @formatter.generate(
-          nil,
-          Hash[params],
-          {},
-          lambda { |k, v| parameterized << [k, v]; v })
-
-        assert_equal params.map(&:to_s).sort, parameterized.map(&:to_s).sort
-      end
-
       def test_generate_id
         get "/:controller(/:action)", to: "foo#bar"