hi, probably discussed many times before, but oil search brought up too many hits. So any recommendations for high mileage 2 litre type 4 engine. Have been using Morris Golden film SAE 30w. Seems ok, but currently changing pushrod tubes and seals. Before I refill with oil I wonder if something thicker like 20w - 50 Morris Maybe worth a try ? May help resist weeping also? If there’s potential for other problems changing to this higher viscosity then may be not worth trying at the moment ? Any thoughts?