Now you mentioned, I remember reading it somewhere. But make sure it doesn't exceed 30% coolant. Meaning keep to one bottle for the SW20 as the pipes are long and you should be well below 20%. As for normal cars that take only a few liters of coolant, you may want to check the exact amount, cause one liter of coolant could end up being just about 30% of a 3 liter system, like used on most small engines. Again, please read on the coolant info, too much antifreeze damages the engine......errr..i think at toyota LLC bottle written never exceed 30%coolant-70%water ratio if not mistaken.....