Is chilly out today, started my jeep to go to work, warmed up fine, on the way temp gauge went from middle 210° to 130° area my guess and just sat there.

Guessing the stat opened and didn't close, any other ideas on what it could be?

 

I just changed mine to a fail safe thermo git it at auto zone I think it was like 12 buck couple of xj folks told me to get this one it's a little better made its not supposed to stick

 

I buy my stats exclusively from Jeep. Never had a failure in 38 years. I find they have better temp control than other brands.

195 degree is the correct application for 98.981298542987561% of the 4.0 applications.