Back again, with the 1994-ish Volvo 940 with many miles on it. (It’s in El Paso; I’m in MD. A friend gifted this car to my son and his wife for their year in El Paso. Free cars are not.)
Symptoms reported by son: coolant leak near firewall (radiator hoses replaced a few weeks ago); maybe some pressure in cooling system; some oily stuff in the coolant in the radiator.
Shop’s diagnosis: transmission cooler leaking. (Well at least it’s not the head gasket!)
Recommend, for $500: replace radiator (yup!), cap (sure), thermostat (all right, but we get rid of this car in six weeks), and … flush the transmission (alarm!).
Usual advice on this forum is drain and refill tranny, rather than flush. However, seems to me that with high risk of coolant in trans fluid, flush is the right action.