0331 cylinder head questions

Hey guys... so I've been doing some searching and can't quite find the answers to my questions. I have a 2001 with 121k miles on it. Runs great, no problems. It appears to have been well maintained. It doesn't lose any coolant, the oil isn't milky, etc... It holds a pretty steady 195-210 on the highway and general driving. Am I going to be doomed at some point? Is it rare for them to crack? Is it something that I should worry about before it happens? Any information is much appreciated. Point me in a direction or shoot me your thoughts.. Thanks in advance!

Just keep on trucking and don't worry about it. IF and when it goes out, then deal with it. I'd venture to guess that the odds are more in you favor.

Typically, they seem to crack after a severe overheating, other apparently for no reason other than the weakness in the casting.

I ran mine hard for two years (didn't neglect it) and after a cooling system problem causing an overheat, it became apparent. 110,000 miles at that time.

Yeah, that's what I figured. I just recently picked this one up. My previous XJ was a 92 and that was quite a while back. I've got some random maint that I want to do on it so I'll be flushing the system and replacing it as well just to be on the safe side.