F8X BMW M2 M3 M4 Coolant / Antifreeze (2015+)

Sometime in 2019, BMW switched the factory coolant formula from blue to green, so this greatly affects the 2015-2021 M2, M3 and M4 (F80 F82 F83 F87) models as the techs say it was not a hard cut-off and some later models did get filled with blue. BMW does not recommend mixing coolants. Visually inspect if your existing coolant is blue or green. (When in doubt, flush and go green. DON'T add blue to green!)