What cause the oil to get in radiator
Motor Oil or transmission oil? Failed Head gasket comes to mind for engine oil. Failed Radiator cooler if it trans fluid.
if your oil level is low and you see the gunk(water oil mix) in the radiator is an internal oil leak, sipping into the water.. not a head gasket issue.. if oil levels are good and the water levels go down and overheating, then it's the head gasket issue... either way is not good. As long as it doesn't overheat and the oil is going into the water system, then you'll be fine for a while.. just keep an eye on the oil level, but you will need an engine sooner or later..
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