Is it possible to have a bad fan clutch that has plenty of resistance? The reason I ask is that my 04 is running warmer now that the outside temps are cooler. I'm running about 5 degrees warmer on average in 40-50 temps vs summer temps. All new cooling system, bled properly, 180 thermostat, yada, yada, yada. Is it possible that the cooling system with all new parts is so efficient that the thermo doesn't have enough hot coolant hitting the bypass to open it until much later? Not overheating, but have seen 210 idle at red lights when I was at 203-206 this summer. Drops immediately once moving. If I let it idle for 10-15 minutes, and intake air temp gets above 130 or so, it will idle at 197 steady. It's almost as if the radiator is cooling really well and cool coolant is hitting the thermostat after short stops or city driving and not opening soon enough, or the fan clutch is too cool to lock up when under hood temps are cooler. Running 194-195 on straight roads at 50 mph like it always does. Still hits 188 down hills. Very strange...

 

I don't think you have a legit 180 thermostat. I say that because even in the summer in 90 degree + weather, at idle, with AC on I hit 194 and under load it will drop to 184.

I can't say if you have a fan clutch issue or not but, check to see if there is play in the fan.

 

Check for air as well, through the bleeder screw I was having a few heat issues turnout my throttle body heater had an iffy clamp fixed that and topped her up no problems since.

Your fan heats up based on temp passing over it usually, so it is possible your clutch is iffy

 

180 stat is legit. It is a Britpart that replaced a genuine grey 180 this past summer. No air in the system.

 

 

My temps are a lot closer to yours than other posters. 188 or 190 when cruising and 204 ish when stopped. I think my issue is the fan assembly (2004) but don't have much to base that on. I think if it were a T-Stat issue it would be higher when moving. I will probably replace the fan clutch and fan assembly next month and will report back.

 

I just posted about this... but was thinking it was my condenser fan not working. I have the 180 stat as well. It almost never went above 194 in traffic and I'm usually in stop and go around the city (Atlanta). Now that it's colder out I'll drive around at 188... but just yesterday I was stuck in highway traffic and was getting up to 210 and it would go back down to 197 once I started moving. Outside temp was around 68. The viscus fan seems to be fine... it has the right resistance when pushed and spins strong with the engine running.

It just doesn't make sense that I'd be getting such higher temps on the Ultra Gauge with cooler temps outside.

Anyone else want to chime in? Are we all getting water pump issues at the same time?

 

Sounds like clutch fan issues to me.

 

My water pump is less than a year old. Nothing changed but the temps. Drove today, 50 degrees out, on a long 15 mile flat road at 50mph, 188-190. Stopped at light, hit 208. Stopped at home, 208. Let it sit idling, 197-201. It just seems to heat up quick at stop and go, red lights. Drops down fine when moving or long idle. I think I might warranty my HD fan clutch as a first measure. Seems super viscous hot and cold. Seems to be working fine, but who knows. Very weird.

 

Could be radiator related. Its definitely a "moving air" issue. When my clutch fan got weak, my temps would slowly climb at idle, OR if I was climbing a slow 4x4 hilly trail working the motor, it would slowly climb in temp to 210 or something, and I'd get Ultraguage paranoid. I think the clutch lose some rpms making them less effective with age.