At the 20,000 mile oil change on this 2024 ford Bronco with the 2.7L engine I noticed the coolant overflow tank was near empty. I filled it back up with the OEM prediluted 50/50 fluid; it needed about 1 qt to get to the max line on the tank. It has a 12.4 qt system capacity.
After a few days and ~50 miles it was back below the min line so I filled it up again, it took about 1/2 qt to get to the max line this time. That was about 10 days & 500 miles ago and it has held steady since at the level in the picture.
After I filled it I noticed these brown specs in the tank. They don’t seem to be floating in the fluid but rather are adhered to the walls of the tank (don’t move when the coolant is sloshed). I tried to wipe the outside of the tank to make sure they weren’t on the outside and they weren’t. They might’ve been there before the fluid went in but contrast better against the yellow fluid. They are also all over the top of the tank where there isn’t fluid but are harder to see.
Has anyone seen this specific symptom and what should I do about it?
I made an appointment with the dealer since it is under warranty. There is no sign of coolant in the oil analysis.
