I guess we will never know for sure. But its certainly possible. Especially if the gap between the head and the block was much worse in low temps. Well, I think the next thing to do is pluck the block out of the engine bay. I'd want to do that no matter which path I choose. But I'm thinking, maybe I look at the crank, and if it looks like I could get away with just new shells, maybe I source another block and try to build her back up. Looks like heads are easy to find. This truck is just a fun daily, so it doesn't have to be absolutely dead nuts bullet proof. So with my rotating mass, maybe I can patch something decent together for a cost I can live with and get a few more years out of it.