[wapiti1]

I have searched this forum for my answer. I hope this is not redundant.
My stock cooling fan serges occationally when climbing passes with a load. The fan comes on and stay,s on untill it cools, and then shuts off. Once in a while it will start serging on and off, I don,t notice any power change, just the noise of the fan comming on and off. Has anybody experienced this? Is this a normal quirk?

Thanks

 

[SCUFFY828]

pretty sure what you are seeing is normal, the pcm takes the engine cooling temp and if it sees it needs more fan then it will engage the fan , the duty cycle of the fan is determined from different inputs , load , ect, etc. how much the fan is engaged is determined by those readings , i guess what im getting at is there is no set schedule for the fan , if the pcm thinks it needs it then it will be engaged

 

[Blakehorton]

Mine has done the same exact thing. either when i have a load or idle it in the 100 deg texas weather along time. dont think its to much to worry about its an 05 6.0 only problems i hade was the egr and rubuilt the turbo on it.

 

[2005F250]

My fan will come on cruising around and when I'm pulling a trailer the thing will scream.

 

[dieselmt]

Not much to worry about unless it does'nt shut down on its own. Then it will have to have a new hydrostatic fan clutch & reprogram the ECM. There are reprogram issues w/ trks. w/ snow plow & other attachments which controls the fan more when it is needed to keep the temps down.

 

[paulpe99]

Yeah, that's normal. My old fan used to do that. Like was previously stated, numerous factors (ECT...) are used to determine when it kicks into a higher fan speed. My problem is my new fan assembly doesn't spin faster than low speed. I've been getting higher temps than before. I don't hear that distinct howling anymore. And i've had oil temps up to 252 degrees lately.