Recently resolved a driveability issue, new injectors, but during my diagnosis and testing someone here recognized my low running ECT.

Q1 What replacement thermostat is recommended,AZ, Oreilley,NAPA and what temperature.

Q2 What problems could be created by running with low temps?

Thanks for everyone's help.

 

How low of a temp? I run 181 to 185 most of the time

 

Thats a good point! Runs at 172- 180. Really tough to get it above 185. I think normal 185 to 195. maybe I shouldn't be concerned.

 

OEM thermostat preferrably. You should be running at around 190*. Lower temperature results in lower MPG.

 

Only use Ford t-stat. When it fails it will fail in the open position.Others may fail in the closed position and barbecue your engine. Just a warning.

 

Motorcraft t-stat only and you should expect temps around 190 with a good t-stat

Josh

 

You need a new t-stat

Josh

 

My 05 runs consistantly between 194 and 204 depending on load and ambient. Diesels have no spark plugs and rely on compression and heat to run. The higher the more efficient within their design parameters.

 

I usually run 184-190 in the winter. 190-200 in the Summer. My stat's stayin in.

 

I have replaced it twice with ford parts and the temp does not change

 

I find this interesting, especially due to your location. I'm running 185-186* with occasional increases to 192*, but it's below freezing here, even the teens. It makes me wonder about my fan and whether it's kicking on too early?
I also have replaced my T Stat.

 

during the summer it will run 190-195, and on a long pull i can hit 210. But in the winter it is mid 180

 

Seems odd. It can be zero degrees and ill see 190-192 cruising at 65.

Josh

 

What about your oil temperature? Is it within 15* of the coolant temp. even the ECT is in the mid 180?

 

even when the truck was new temp was mid 180.

Oil temp is another story, i need a new cooler so i am running 210 to 220