diff --git a/lib/6to5/traverse.js b/lib/6to5/traverse.js
index acba99bc26..db22293a35 100644
--- a/lib/6to5/traverse.js
+++ b/lib/6to5/traverse.js
@@ -85,6 +85,7 @@ function traverse(parent, callbacks, opts) {
 
 traverse.removeProperties = function (tree) {
   var clear = function (node) {
+    delete node.extendedRange;
     delete node.tokens;
     delete node.range;
     delete node.start;
@@ -97,10 +98,7 @@ traverse.removeProperties = function (tree) {
   };
 
   var clearComments = function (comments) {
-    _.each(comments, function (comment) {
-      delete comment.extendedRange;
-      clear(comment);
-    });
+    _.each(comments, clear);
   };
 
   clear(tree);