[ToySub1946]

I have a 2015 FRS, purchased new, now with 21,330 miles on it.
Noticed coolant somewhat low when it was new...after some miles driven...radiator was full, but overflow bottle showing no coolant.

Finally topped it off to low coolant level when odometer showed about 17,000 miles. {I don't allow the Dealership to add any fluids during oil and filter changes}

I used Best available Prestone brand, as FRS coolant was same color (green)...and I see no point in buying Prestone coolant which is premixed, as full strength coolant price is more product for the dollar.

I'd guess these cars, when new, have some bubbles in the cooling system, so they can't get them totally full at the factory.

I've found no leaks from my car, so no worries...just a normal situation.

Bottom line: I'd drive the car a while before worrying about it's coolant level...see if it gets any lower...then add as necessary. As long as you check coolant level in radiator itself, [certainly with car cold], if radiator itself is totally full, no real worries for a while.