I just bought a 1991 Ram 250 , 2 wheel drive that had the Killer Dowel Pin problem. The owner replaced the engine with a 1993 Cummins with 69,000 miles on it. The engine came out of a wrecked truck and had been sitting for two to three years. Once he got it installed and running he soon found the oil was milky. He changed the oil cooler gasket but that didn't solve the problem. He was told it was the head gasket by a diesel shop. He was burned out on messing with the truck and I purchased it. I got a new head gasket thrown in with the truck. What all do I need to be looking for? Could this be some other problem? Do these heads crack easy? I am a diesel newbie and will appreciate all the help I can get!

 

check your overflow bottle!!!! If it has oil in it, you don't need to have the head gasket replaced you need to replace the oil cooler and man it a mess to get the oil out of there

 

Pressure test the oil cooler (built into the filter mount) before you tear the head off it.

The early trucks had cracking problems around the injector bores, but from '91.5 up they used 7 mm injector tips to give more meat in that area. A blown HG is not unlikely on a truck that's been turned up a bunch, but not real common on a stock engine.