head gasket or cavitation?

[giezy]

well in the the summer the truck over heated and blead the compression into the rad and I parked the truck and hasn't run the truck for 4 monthes and there is a oil slik in the top of the rad now but it started right up and idles ok now but need to know if it is a gasket or the block the oil is fine and doesn't burn any I have read the stuff here but they are all little different symptoms

Just looking for feed back before tear down I have a spare but unshure about how it runs

 

[giezy]

forgot to add the pump and injectors have been done two years ago and the rad is new and the oil cooler doesn't leak. there is some blow buy coming from the oil dipstick when pulled to

 

[Kevin 007]

If this oil film and pressurized rad was noticed after the engine overheated; I would suspect that it would be a head gasket issue.