Oil cooling system

Usually, the reason for oil in the cooling system is because of a blown head gasket or a leak in the radiator where the transmission cooling line passes thru. Brown milk is engine oil, pink is trans fluid if the car is an automatic shift.

WOW SOUNDS PRETTY BAD ,THE OLD MOTOR PROBABLY JUST NEEDED THE PLASTIC INTAKE ON TOP OF THE MOTOR 280 AT AUTO ZONE THEY WERE KNOWN TO CRACK AND LEAK.SAME DEAL ON THE F150S.SOUNDS LIKE YOU GOT A BAD MOTOR

Not uncoomon. If you look where the oil filter is in the front of the motor by the radiator. Where the oil filter screws onto is the oil cooler and has coolant passing around it in a jacket. The oil pressure is greater than that of the cooling system pressure. Replace that cooler and flush the cooling system. This should cure it.

Print

REMOVAL & INSTALLATION

1. Disconnect the negative battery cable.
2. Remove the thermostat to drain the cooling system.
3. Remove the oil filter.
4. Disconnect the hoses from the cooler.
5. Remove the nut holding the cooler to the oil filter base and remove the cooler.

To install:

1. Position the oil cooler, then connect the coolant hoses. Tighten the nut to 18 ft. lbs. (25 Nm).
2. Install the oil filter and the thermostat.
3. Fill the cooling system and connect the negative battery cable. Start the engine, allow it to warm up check for coolant leaks.

these run about $50

That is more than likely a coolant hose and not an oil hose. The cooling systems have what is called a by-pass hose which by-passes the thermostat in the engine allowing enough coolant to flow and warm up thus sending it to your heater core so you get heat inside the car sooner.

It's possible that the old head gasket has de-laminated and the oil is passing through the inside layers of it. That is sometimes difficult to see.
Too late to check now but you should have checked the oil in the engine for coolant intrusion. Once apart, there always will be some in there so looking now is not valid. (why you always need to change oil after changing a head gasket).
Some '00 4.0L heads develop micro cracks that are difficult to find...it's possible you have an earlier head than the vehicle build year.
Also, have your radiator tested.... there is a transmission oil cooler in it if it's an automatic trans.
If it fails, you will also have oil in the cooling system, but it will be trans oil.
If you originally had coolant loss and steam from the tailpipe or you had a hydrocarbon test done on the cooling system I'd suspect the gasket or the head. If not, put the new gasket in and have the radiator tested. Same as coolant in the engine, if the cooler went bad, change the trans oil.
if it turns out to be micro cracking, either replace the head or use one of the high $ block sealers
to stop the seepage. 'Though I don't like using sealers, on micro cracks they seem to work pretty well if the directions are followed exactly..

The following are the most important symptoms with severity:

1. Leaking radiator.
2. Overheating and change of oil to milky appearance.
3. White smoke from exhaust
4. Coolant leaks.
5. Low of compression.
6. Coolant in cylinders.

DRIVER SIDE LOWER CORNER OF RARIATOR JUST BELOW ENGINE OIL COOLING LINES. {NOT TRANS. COOLING LINES} IT IS BLACK, FLAT AND ALMOST IMPOSSIBLE TO GET TO !

HAVE A GOOD TRANSMISSION INSTALL A AFTERMARKET COOLER LIKE TRANS COOL, THIS BY PASSES THE FACTORY COOLER

If it is oil it can pass via the head gasket, it is rare but has been known to happen. If it's an automatic and has a pinkish brown color it could be a failed radiator trans cooler.

I would assume the truck is an automatic. If the oil is red in color or pink in the radiator then you may hae an oil cooler leak. The auto tranny cools the oil by passing the oil through the radiator in tubes. If these tubes are leaking you would experience the oil leaking in to the radiator. The other worse scenario would be that you have a cracked cylinder wall that is leaking motor oil in to the crankcase. Good luck