i have a 97 chevy 5.7 1500.as of yesterday i have oil in my radiator and water resevoir.i dont think my block has cracked ,it hasnt overheated at all. i did have a small leak in the radiator and added stop leak a couple weeks earlier.is it possibly more than replacing the radiator?and whats the potential damage?
Check Your Engine Oil And Transmission Fluid …
See if either one of these is low or “milky” with coolant contamination. coolant could escape a cooling system through a faulty head gasket (mixing with engine oil) or radiator (mixing with transmission fluid). Read on.
Engine oil could get into a radiator most likely through a head gasket leak. Automatic transmission fluid could get into a radiator through an internal leak in the radiator’s integral transmission fluid cooler section.
There is room for potential damage if the fluids are contaminated and you keep running it or if any fluids get too low.
You may need a new radiator or a head gasket diagnosis and repair, and likely a transmission fluid change, and an oil change.
CSA was right on the mark, and he explained it very well.
(I just hope that METOO2 isn’t offended by my statement of agreement!)
Easy VDCdriver; you’re piling on. 
(with a faint squeaky voice i concur)
I Agree With Ok4450, Agreeing With VDCdriver, Agreeing With Me.