Truck runs hot!

[Claytona08]

My truck has the original 4.1L inline 6 in it with right at 100,000 miles on it. I haven't driven this more than 100 miles since I bought it in March of 2013. Well I decided to drive it to work last Friday which is approx 50 miles away. As I was driving about 20 miles in I noticed that my temp gauge started creeping up past the normal temp of 180ish. It got all the way to 230-235 before I pulled over and let it cool off. That evening when I got home I talked to a mechanic that said the reason for the temp creeping up was that the head was cracked on the engine. Trying to get some other opinions before swapping the engine out.