I have a 2012 RAM headgasket and studs water pump thermostat was all done about 6k miles ago.

One day in the summer, I noticed a puddle under the passenger side of the truck and thought nothing about it because I had remote-started the truck and figured it was from the ac.

Well got about a 1/4 of a mile and temp jumped up to 245; I pulled over, let it cool off, topped it off, and went home.

I contacted the shop that did the work and took it back; they pressure-checked the system with no leaks, got the truck back, and drove it every day for a month with no problems; then, one day, I drove it, and it lost all the coolant again.

Back at the shop, they recheck everything, and the pressure check is good no exhaust gas in the coolant; I'm at a loss.