I have oil in the radiator. What would cause this? on 1990 Chevrolet Corvette

350cc engine

Asked by for the 1990 Chevrolet Corvette
Auto. or man. trans? Oil cooler or not?If either auto trans. or oil cooler.poss. rad. trouble.
Now do you see any coolant in any oil's? Radiator most likely suspect.
Auto, no oil cooler
Now,oil cooler,if equiped,is an integral part of the radiator. Are you sure it does not have one? Auot trans. has two
lines going to the rad. located on the passenger side. Oil cooler has two larger lines going to the rad.on
the drivers side. If NO oil cooler, most LIKELY suspect is trans.cooler which is also
an integral part of the radiator. Either case susspect RAD.