A month or so ago my thermometer started reading pretty low (a little over 1/4) so I figured the thermostat must be stuck open. Finally got around to replacing it and it's not any better, might even be a little worse. What else could it be? Next thing i plan to try is replacing the sensor but anyone know anything else that could cause it to read low?

 

Not sure, but if you get an OBD wifi connector you can look at diagnostic stuff with your phone. This includes seeing the temperature as a digital number. The obd connector only costs around $20 (elm 327) and the app for phone is maybe $10. That would at least tell you the temperature the thermocouple thinks your coolant is. Perhaps the gage on your dash is wrong.

 

That is exactly what I'd do. Well, I keep Torque Pro running at all times on my Nexus 7. Everyone should, and most especially if you're troubleshooting these kinds of problems because it does let you look past the instrument gauge and directly at what the sensors are reporting. One-quarter on my Jeep would probably be about 100-125° coolant temp. No way your Jeep is running that low--which immediately suggests a sensor problem. But, Torque Pro can confirm that reading. And many, many other readings as well.