diff --git a/lib/gdk/diagnostic/ruby_gems.rb b/lib/gdk/diagnostic/ruby_gems.rb
index 796ea88ffce722bd68ae8e9a5d0a8460e5bb2d79..4c8daef3e2b365a8ec217dd12443f654662873de 100644
--- a/lib/gdk/diagnostic/ruby_gems.rb
+++ b/lib/gdk/diagnostic/ruby_gems.rb
@@ -50,7 +50,15 @@ def gem_installed?(name)
       end
 
       def gem_loads_ok?(name)
-        exec_cmd("#{bundle_exec_cmd} ruby -r #{name} -e 'nil'")
+        command = -> { exec_cmd("#{bundle_exec_cmd} ruby -r #{name} -e 'nil'") }
+
+        if bundler_available?
+          ::Bundler.with_unbundled_env do
+            command.call
+          end
+        else
+          command.call
+        end
       end
 
       def exec_cmd(cmd)
@@ -59,6 +67,10 @@ def exec_cmd(cmd)
         Shellout.new(cmd, chdir: config.gitlab.dir.to_s).execute(display_output: false, display_error: false).success?
       end
 
+      def bundler_available?
+        defined? ::Bundler
+      end
+
       def gitlab_error_message
         <<~MESSAGE
           The following Ruby Gems appear to have issues: