So Toyota has 3 different kinds of RTV for engine/transmission sealing - 2 similar but different black RTVs and a orange one for transmission diff sealing. One of the black RTVs is is for oil pan/valve cover/camshaft housing applications, and the other is for water pumps and anything touching their coolants. I had the former RTV on hand, but I used it to seal the thermostat housing to the water pump but I also realized this part also leaked quite badly when I had Toyota Pink PHOAT coolant and it was sealed with the oil pan RTV. I plan on filling the cooling system with the old red coolant which has no organic acid inhibitors, but will I be fine or should I reseal this joint with a sealant that can do OAT coolants?