My Radiator Reservioir Tank is a milk shake, the engine oil cap and dip stick is clear. Is my radiator bad?

Check you transmission fluid condition if it is automatic. It could be if the transmission fluids are like milk shake as well.

You have contaminations in the cooling system and if it is not due to the transmission cooling leaking into it, it is not the fault of the radiator.

Ok, in that case most probably the coolant has long expired and requires replacement. You would need to flush the system before replacement of coolant. One time flushing might not clean the system sufficiently and it would be best to drain out the coolant, refill with water and run the engine till operating temperature.

Drain again and flush. Repeat a few times till the water becomes clean before refilling with coolant.

One way of expediting the process is to disconnect the heater hose or if there are stoppers along coolant pipes and plug in a hose to flush.