[dannyboy950]

Sorry for the delay this is not a maned forum thee may not have been anyone here at the time of your post. I will try to help.

While your temps are not excessive for that much ambient temps, your fan clutch shows to not be working correctly. From my own observations you should be turning up at least half engine rpm at those temps.

You may need a new fan clutch.

 

[dannyboy950]

And when the truck is stopped or slow moveing the engine quits generateing heat?

This is why the computer controlled fan clutch was developed, to provide a more reliable and consistant control over engine temps under all operateing conditions.

Ford chose to do this by useing an infinitly variable speed high volume fan force feeding air thru the heat exchangers as needed only when needed to reduce drag on the engine.

I am feeling too poorley today to get into a debate on this so I will let one of the other Ford techs with access to fords current information. Mebe M-chan 68 or dave or one of the others will chime in.

Basicaly the pcm compares more factors than just coolant to oil temps to turn on the fan.

 

[dannyboy950]

I think so also but since ford has not published a chart listing fan speeds in relation to temps, or none that I have ever found. I would really like to see one. It is really hard to say for shure. I guess that is proprietary information.

By the way the my post 7 was meant for urban assault vehicle not to you. Sorry I forgot to click quote button.

 

[dannyboy950]

Well useing your own Wind tunnel theory, would you not exspect a free wheeling pin wheel to be turning a little faster than 425 rpm at the air velocity geneated at 65 MPH.

I am not a Ford mechanic just and old diesel mechanic of 47 years experience who also used to build race cars and engines. even built a couple for a guy named Garlits.
The guys temps were not in question they were reasonable underr the circumstances.
Just his fan speed as designed by Ford seemed a little low could cause him some problems pulling a grade while towing.

Thats all I got to say. OP good luck.