off the shelves at Walmart I’ve used Pennzoil PPPP, Royal Purple, Valvoline EP, and in now Mobil 1 EP all 0w20. If I had to rate them by feel and smoothness of engine I’d say Royal Purple followed very closely by M1, Valvoline ep and did not like Pennzoil. I did UOA on RP and Pennzoil, Valvoline...