I guess there is no way to completely drain ALL the antifreeze at once. Rather, we have to drain 2-3 quarts, add 2-3 quarts, repeat several times. Is that correct? If so, I’m not convinced that I have 100% new coolant in the system once I’m done. Is 75-90% new coolant considered close enough for Ford work?
Hi Juan, I'm going to replace the coolant in my 18 mustang. The way I'm going to attempt this is to drain from the radiator then vacuum fill with fresh coolant, drive around until I've done around 200 kilometers , drain again and repeat the process. Check the coolant strength with test strips and repeat the process until you are satisfied with the results. Cheers from AUSTRALIA. Vic
