driving home yest. from work truck got plum hot. pulled over. 1995 cher. 6cyn 220000. miles. added as much coolant as i could. didnt spew over no stean just was really hot on the gauge. got it home ran the heater. looks to have a relatively new water pump "still kinda shiny" my guess is thermostat. anything else. thanks guys

 

So it was low on coolant? If so, you need to find out where it's going.

 

How hot did it get, and was the electric fan running?