Why does my antifreeze in overflow have a pinkish tint

1997 olds 88 86700 miles. I notice that the overflow was really really dark. I stuck a napkin into the tank to pull some gunk out for a better look. The napkin looked like it was redish pinkish in color along with the nasty sludge. The antifreeze is green. I've been reading the coolant lose no visual signs info. nothing mentions pink antifreeze. The oil is clean, and a qrt low. Wouldn't the coolant lose end up in the oil on these cars from what I've read, that is my understanding.

Its possible the radiator is leaking internally. The radiator has a transmission cooler in it. If that cooler is leaking then you could have tranny fluid in the coolant.

Would the antifreeze be in the trans fluid also? And is it pretty much a given that my uim needs to be replaced.

You may have coolant in the tranny, but not necessarily. It would depend on the leak and pressures involved. The rad is only under pressure when hot the tranny lines are under pressure constantly when running. If its one of them 'only when cold leaks' the tranny fluid would flow into the coolant until it warmed up and sealed itself. Without seeing the car this may be way off base, but it is a possibility.

My trans fluid is clean. I find that very strange that on fluid could leak into the other, and not vice versa. Well, I may have 2 problems. I am under the impression that if the uim is warpped and leaking the oil would be contaninated/milky from the antifreeze. My coolant resv. is empty, the car smells like antifreeze after a long drive(45mins.) but my oil is clean and actually a qrt. low. Does the antifreeze burn off of the block if it sits somewhere? Or is it getting into the cylinders? No white smoke is apperent, so that is also what sort of puzzles me.

The manifold depends on where it is leaking. I have seen where it would leak externally, no coolant would get into the engine and the leak would be slow enough to burn off before it would drip to the ground. If you do not have a radiator pressure tester, most chain type stores will pressure test your coolant system for you. Or they may "loan" you the tool to check it out. That way you do not have to wait for the engine to be warm for the coolant to be under pressure. If coolant is leaking externally slow enough to burn off, you should be able to see it though. Not necessarily the coolant, but the white trail it leaves behind. Check around the water outlet, thermostat and the corners of the heads.

Tks for the help. I will check those spots this weekend, and see if the psrts store will lend a tester.