Engine/Transmission (1994 - 1998) Oil in the Radiator

[NScott]

I checked the radiator level by taking the cap off the other day and it spit about a cup or more of black engine oil out of the filler neck. I've read some threads on this subject and most agree that it must be either the oil cooler or a blown head gasket. Question is : How does one tell which it is? Could it be anything else? If it is the oil cooler, can it be repaired {brazed} or does it have to be replaced? Does anyone have the Cummins Part # for the oil cooler? Where is the cheapest place to buy it? Any help on my problems will be most appreciated!!







98 3500 Cab & Chassis 2WD 12V 5Spd

Bought it recently used and don't know if was/is BOMBED!!!

 

[redram]

I would bet that a replacement oil cooler would be available through the Cummins dealer or more expensively through the Dodge network.



I've not heard of too many coolers that have developed leaks.



Can it be repaired? Probably if it is just a pinhole in some of the tubing. Pull it out and check-it. A good craftsmen that has welding ability should be able to fix a minor problem.



If it's a head gasket or the cooler, you should be able to have this checked with a cooling system pressure check. It's either going to leak into the oil system by the cooler (in the block behind the oil filter) or into the oil system on the head.



Sorry to hear the bad news but I hope it's the lesser of two evils.

 

[JWaters]

I have replaced a few of these, and Yes I bet it is your oil cooler, easy to replace!



Good Luck.

 

[4dodgepoor]

oil in radiator

Same thing happened to me on a 98 12v 3500. I pressure checked the oil cooler no leaks. Feared cracked block. Long story short, I installed the oil cooler with out the oil filter housing that goes on top of the cooler, using larger nuts under the bolts to tighten the cooler in. Then I pressurized the cooling system, I could hear the air leaking out through the oil gallery that is now open below the oil cooler. By adding water and waiting till I heard air again, I measured the level in the radiator and by using a level measured down on the motor , determined that it was the head gasket. It was a leak between an oil passage in the head gasket and a water port. Later found out that engine had the fuel plate moved up and the wastegate disabled. Head also had to be replaced, cracks around the exhaust valves. Good luck

 

[HVAC]

Headgasket

I've seen a head gasket cause that problem. There are oil passages through the block to the rockers. The oil pressure is higher then the pressure in the coolant system. So the oil can push it's way into the water passages.