OK I just replaced my fan clutch because it was dying. I did the same thing, turned it and tried to wiggle it, etc. I initially thought mine was OK but it wasn't and it took me forever to figure it out because all the tests seemed to be good. People would tell me it should turn "smooth" and it should be "hard" to turn when hot...how smooth is smooth and how hard is hard? It's hard to tell what people mean.

Then I found out there is a way to LOCK the fan clutch in place so that it is directly coupled to the engine. I don't know if the newer ones have this, but mine did. Check this out before listening to me.

If you can lock your clutch and the sound goes away, that would tell you your clutch is making the sound.

But also if you have a silicone clutch which you can lock manually, (I think you do but I could be wrong) here is a simple test to see if it is working. (not regarding any squealing issues) You might want to have someone else with you for a second opinion.

Wait until the truck is bone cold-- like overnight. All the silicone in the clutch will have settled and effectively locked the clutch up. Roll down the windows and start your engine. You should hear the roar of the fan because it is locked up. Stop the engine. Lock the clutch manually. Start the engine again. If there is a HUGE difference in sound, with the second startup being very loud in comparison, your fan clutch is going out.

FYI, I went with a replacement clutch, a mechanic I know said NOT to go aftermarket to by OEM because he has seen a lot of aftermarket ones fail. I thought about efans but then I'd have to upgrade my alternator and it would just get into too many other issues and $$$$. the supposed better mpg would never pay for the $600 I'd be putting into it.

Hope this helps!
-Andrew

 

Well, how do you lock it???

I am thinking mine is bad due noise on hot days... but, so tell me how to lock it? Thanks

 

Efans!

 

Wow, old thread of mine- guess I should update it. Noise (whistle) was I'm thinking the a/c clutch/compressor combo. Since they've been changed, no whistle. That's my guess anyways. However, I did put e-fans on anyways which solved nothing but works good. If you want to lock the fan, the clutch will do that when needed (seldom) this way you keep the shroud as well. Going to a solid mounting fan would need alot of changes not really adding benefits anyways.

 

A solid mounting fan will sound like an airplane and noticeably hurt the performance and gas mileage.

 

I have a 2000 F150, 5.4
My mechanic said it was the fan clutch so we replaced it and noise was still there but this time it was on and off so I assumed the new piece was defective, I exchanged and replaced it a second time and noise is still there!, not all the time but most of it. Whenever it goes my truck's engine feels smooth and strong but when the noise comes performance is not the same.