Patman
Staff member
I agree, Amsoil's new 5w40 would probably be a great year round oil for your Jetta. Although if you didn't mind switching viscosities, you could always go with their 5w30 in winter and their 10w40 in summer. Despite what your owner's manual says, Amsoil 10w40 would definitely be good to temps above 60F. In fact even Amsoil 5w30 could handle the hottest summer day in Toronto, so you could even use that year round and still get a very long engine life.