There 5w-30 has the best add pkg out there. Many have used it with great results. There 15w-40 is also has great add pkg with about 3,900 ppm of Ca and like 1,400 ppm ofZn and 1,300 ppm of P. The 5w30 will not shear as much as their 15w40.
The 5w-30 is better but I do not think it is needed, unles oil testing says it helps more or better. For the increase in price I would say you would be better with there 15w40. This point is a good ref but not real world. 5w30 is -60F and 15w-40 is -51F. Good luck.
The 5w-30 is better but I do not think it is needed, unles oil testing says it helps more or better. For the increase in price I would say you would be better with there 15w40. This point is a good ref but not real world. 5w30 is -60F and 15w-40 is -51F. Good luck.