google is ur friend: just go quaker state viscosity, and the following shows right up, it's number one, you don't even have to look far:
------------------------------------------ 5w20 ----- 5w30
CCS Viscosity, cP (°C) ASTM D-5293 4,790 (-30) 6,100 (-30)
MRV viscosity, cP (°C) ASTM D-4684 12,100 (-35) 19,100 (-35)
notice how both oils are 5w. see how fast the 5w20 runs compared to 5w30, at temperatures that actually regularly take place where i live. alright, please explain how these manufacturer measurements are so "sadly mistaken" can i take my xanax now?