Could be - Cold vis isnt measured at that temp (0degF) the xxW SAE-J300 designations are determined at much lower temps, maybe 5 deg near where they become plastic. Actually thinking they may cross near zero deg though, visc calc arent good at these temps - its a log function not linear. You HAVE to talk specific oils as the MRV# vary greatly - ex: the M1 0w-30AFE is almost 1/3 as viscous as a M1 0w-40, 11k v. 26K cP at -40c respectively. Note that Base stock are improved, my rotella T dino 10w-30 has a pour of -40c.