Hi all! I have a 2015 Kia Sorento 3.3l v6. I live on a large hill/ mountain, its about 2000 feet higher than the city. The road is fairly steep, 12% on some grades. Most trips are under 15 miles. I have QSUD 5w-20 in it now and will be changing to Pennzoil Platinum 5w-20. Should I go the full 6...