I have a 99 DII with 123k miles. About 3 months ago the truck started throwing a misfire code in cylinder 4. I replaced the plugs and wires and the code did not go away. The truck would have a slight miss from 800-2500 rpms. As I was driving it around the block the temp guage got to about 3/4 (just below overheating) and then the lower radiator hose blew (developed a large hole). I stopped the truck and checked the oil. It had a small amount of water in it. I had my mechanic install a head gasket kit and check the heads for warpage a few weeks ago. The heads had to be shaved slightly. My mechanic then told me that he noticed the radiator was cracked and had it repaired. The truck never leaked antifreeze so I assume the crack developed at the time the radiator hose blew. After replacing the head gaskets my mechanic tells me the truck is still throwing a misfire in cylinder 4, it is blowing white smoke out of the exhaust after running for about a minute and the truck will overheat when driven. The head gasket seems to be leaking in the same spot. My question is, is it the head gasket again or did the engine drop sleeve #4? Any help would be appreciated.

 

If you dropped a sleeve it wouldnt still be blowing smoke. I would say that either the head gasket job was done wrong or you have a cracked head.

 

I"m not sure if the heads were checked for cracks. My mechanic said the heads "were checked" and had to be milled slightly. Coolant seems to be seeping into the cylinder (#4) and blowing the spark out. When I pull the spark plug I can see bubbling from the coolant inside the head. If its just the head gasket again, which seems crazy, then I will make sure they are checked for cracks and use a different mechanic. Thanks for the help so far Spike555.

 

Have someone do a coolant pressure test, that and or a leak down test will tell all.

 

His "checked" could be different from your "checked", they need to be checked for cracks, a visual inspection isint good enough. They need to be pressure tested.
Depending on which head gasket kit he used he may have put the gaskets on upside down. But if it is the same cylinder as before I would bet that the head is cracked.