--- a/sites/all/modules/uc_free_order/uc_free_order.js
+++ b/sites/all/modules/uc_free_order/uc_free_order.js
@@ -32,7 +32,7 @@ function free_order_check_total(total) {
     $("input:radio[@value=" + uc_free_order_next_method + "]").attr('checked', 'checked');
 
     // Refresh the payment details section.
-    get_payment_details('cart/checkout/payment_details/' + uc_free_order_next_method);
+    get_payment_details(Drupal.settings.ucURL.checkoutPaymentDetails + uc_free_order_next_method);
 
     using_free_order = false;
   }
@@ -44,7 +44,7 @@ function free_order_check_total(total) {
     $("input:radio[@value=free_order]").removeAttr('disabled').attr('checked', 'checked').parent().show(0);
 
     // Refresh the payment details section.
-    get_payment_details('cart/checkout/payment_details/free_order');
+    get_payment_details(Drupal.settings.ucURL.checkoutPaymentDetails + 'free_order');
 
     using_free_order = true;
   }