Yesterday I changed my transmission fluid and filter. Drove it about 60 miles yesterday. Today I went to check the fluid level in the tranny and noticed the fluid was also in my coolant expansion tank. I'll obviously replace the radiator, but how likely is it that my transmission is not going to last? Although there was trans fluid in the coolant I didn't see coolant on the trans dipstick. I'm concerned that if the fluids mixed there should be coolant in the transmission as well.