Hahaha I don't think I need all that... That could be someone elses problem
... The new fan clutch made a difference... But
I think it's in the radiator... And the upper hose does build pressure...

 

Hey I was having problems like yours with my 98 4.6L...final result that solved the problem was a dual radiator. That was 6 years ago and I just bought a flex-a-lite electric fan kit a few months ago for it and now I can control the temperature it cuts on and off at and it has a cool down period when you turn the truck off.

 

I am having the same problem. it was overheating when I was towing my travel trailer. changed tstat, still had problem. changed clutch fan, appeared to fix problem, until i was sitting n drive thru w/ a/c on, again it started to get hot (although it appears the tstat and clutch fan helped, as it didn't get as hot as usual). I am replacing water pump and radiator tuesday. i found sediment in radiator, and talked to a ford master mechicanic who said that he has seen impellers in the f150 5.4L water pumps disengrate over time (not many but a few) and sediment build up in those radiators is common. lemme knowwhat works for u,i hate to keep replacing things that don'tneed to be.

 

I've changed all that and the new fan helped while towing... But sense it does it sitting still it's the radiator so I'm gonna change it.. Let me know if it fixes yours

 

Is your fan clutch working properly?

 

Yeah it should be... It's new... You can hear it come on and go off...

 

Sometimes you can have a electrolysis damaged radiator (electrical charged) which will cause corrosion that can ultimately cause over heating problems.....new radiator might be the answer.

 

New radiator today and she is good again!!! Cleaned the old one out and some nasty water came out so it might just need a good cleaning but oh well...

 

haha thats good to hear glad u figured it out.... but hey... at least u dont gotta worry about those other parts for awhile

 

This sounds like mine. It got hot at the drive through this weekend and temp back to normal as soon as I got on the highway. So the fan clutch fixed the problem or did the new radiator?......