In automobiles, radiators are heat exchangers whose primary function is to cool down the internal combustion engines. A radiator cools down the fluids inside by transferring heat to the air outside. In turn, it cools down the engine. Though you can drive a car with a cracked radiator, sometimes, this can be dangerous as it can overheat the engine. This overheating can damage other engine parts and can incur additional repair costs.
Common signs of a bad radiator are overheating the engine, shifting issues, leaks, exterior fins blocked, fluid discoloration, etc. Though you can drive a car with failed radiator for about 5 to 10 kilometers, towing will be a cheaper option as it will ensure that nothing gets damaged further.