Preface: Last month I sold my house and had to move...SO, while packing up the garage and shop I found several of my sealed 4 qt bottles of 5W-30 laying around. They all had about 1/2 or more quart's in each bottle. These were all leftovers from trying to find something that "burned Less" in the ole Prius; Ultra, Platinum, Max-life, M1, Q-SUD and Castrol Edge. So to save time and mainly space I mixed them all together in one bottle. Now I have a full bottle of Heinz 57 semi-synthetic motor oil. I know there is nothing in this "Accidental Super-blend" that could hurt anything but for some reason I am hesitant to run this in a vehicle. Should I run this in a car or save it for the lawnmowers etc?