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First Post :drink
Thought I'd search the forum for a similar symptom of what I got b4 I fire up another post!
I notice my fan engage and disengage regularly, I see it in my mileage, and here it cycling in and out every 3/4 second. It was suggested I check my A/C for issues, none found. B4 I would here the fan for a second then it would disengage and you would here motor revving up, now it cycles so much the temp (BullyDog Outlook) sits at 184 instead of the 192 I used to read... Any input?
 

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.....I see it in my mileage, and here it cycling in and out every 3/4 second.....
Windows down especially, you can hear it cycling in and out quickly, just don't have a G to drop on the electric setup...
 

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The fan is more prominent, windows up, when traveling on the road. When idle, a properly functioning fan is about impossible to notice inside the vehicle.

Not sure this helps you. Maybe I am missing something.
 

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Example: Driving at 60km/h, windows down or up, you will here the fan cycling ridiculously, highway speeds it doesn't cut out... Coolant temp sits at 184 instead of the 192 I was accustomed too, and fuel economy is :rolleyes:
 

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Inlet Air Temperature. It will increase if your fan is cycling. I gotta think you can monitor it on the outlook.

When reporting IAT, report it as degrees in excess of ambient, only while traveling 45 mph minimum.
 

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What's crazy is I don't even need to be moving, at idle, on start up, warm at idle, moving at low speed, you can hear the fan cycling in and out every 3/4sec... IAT is not even a factor I'd think...
 

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I really just don't think you are describing the thermoviscous fan. When engaged at idle rpm, it is not at all audible.

IAT rise is a symptom (result) of fan engagement. That's why I suggested monitoring it. If it increases when you hear the noise, then it's the fan. At this point I have doubts, but that's not an insult to your intelligence, you just aren't describing something familiar.
 

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Yeah I fiddled with the A/C controls to mimick, but no success, and I do appreciate your time to figure this out with me, I've wrenched in many a dealership, and on all my own cars, which is what leads me to believe it's the fan clutch, temp is consistently down, it cycles quickly at city speeds, on full blast at highway speed, and at idle it doesn't let off (from previous times to present, sound difference is noted)... Again, that's why I'm here to find out if someone else has had the same/similar symptoms!
Sorry for the thread jack, personally thought it be best to add to an existing thread of the same issue!
 

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Some more prying, does the thermo-visc clutch operate solely on the air under the hood surrounding the fan clutch to engage/disengage? Does this have any bearing on what I'm after...

"TravelswithCharly:The black radiator top cover is easy to remove. Pull it off and look down between the CAC and radiator for nests.

If it appears to be clear, I thing you may have a problem with heat in the CAC. It is not too difficult to pull the MAP sensor, located under the 6.6 black resonator hat. See if it is melted or damaged."

The IAT mentioned, does it activate the fan clutch, where is this IAT drawn in and measured?
 

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The truest way to determine if the clutch is being properly actuated, is to drop a thermocouple down between the CAC and radiator. If that temp is over 180 while just piddling around, you have some kind of induction issue or ambient air blockage.

FWIW

Do you have a grill cover of any type?
 

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No grill cover, stock, and super clean in and between the rad and IC, I have an infrared temp gun that Ill double check temps with at full running temp :drink
 

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An update to my situation, I have been on the high way lots lately, and with the weather sitting around -20C, I can still hear my fan engaged at highway speeds, I washed out in between the IC and rad even though it was clean already, and my fan clutch heat sinks are spotless... I am thinking of sucking it up and getting an electric fan setup... Suggestions anyone?
 

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take off your fan and come back and report if the noise has gone away. If you are not towing right now, you don't need it.

Electric fans is the surest way to devalue your truck, giving away half your load capability.
 

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Considering the truck idles for periods of time between jobs, I don't see myself removing the fan and clutch... Could the thermo visc clutch be jammed and applying a 1/3 of the clamping force to spin the fan? To recap, the fan basically feels as though it's partially engaged all the time now, symptoms leading up to this were repeated cycling...
 

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Well... Flex a lite has a nice setup that I can pick up locally for 650, part # 284, seeing as I will never tow anything over 10000lb's, the 18000lb limit on the fans should be plenty! This is double the price of the apparently useless fan w/clutch setup that has 'failed' at 98k km's, so in theory this should last twice as long... Any one else running the flex a lite on a Max?
 
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