I found some oil in my radiator, but have no evidence coolant in the oil. Are head gaskets a common problem at all on these engines? I have 167,000 miles on the 5.9. Should I just get a low mile motor from a junkyard and swap it out?

Thanks for suggestions.

 

cracked heads are somewhat common

 

Yeah the heads are known to crack sometimes. If they are get some RT heads, probably cheaper then a junk yard motor.