Having a high temperature issue on my 3.8. 42K miles on the odometer. The temperature is now getting past half way. Between 5/8 & 3/4. No overheat light yet. When at operating temperature and I turn it on it will jump to 3/4 before the fan kicks in on high to knock it down to 5/8. On highway above 55 w no load(level or going downhill). It stays at 5/8. Top radiator hose is pressurized. Thermostat is less than a year old. Fan is operating at low and high. Radiator fins are clear. I do have a rugged ridge bumper w Q9500i recessed winch.
I am leaning towards a weak water pump even though their is no chirp or weeping. However I will flush coolant system before I pay for pump. Coolant is original and never been changed. No gunk at bottom of reservoir but who knows.
Does the radiator have a drain cock? Did not notice one.
Any other feedback would be appreciated.