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Discussion Starter · #1 ·
I have a 2012 limited 3.6l with the normal cooling setup on it were i live we experienced some harsh mornings last December up to -18 F and im assuming this is what broke it but my rad fan doesn't turn on every time when it starts to get home for some reason. i get a really noticeable vibration and the fan doesn't move. but sometimes it kicks on really hard then works OK but as soon as i turn off my heat from HI and turn the ac on i start racking up the temps the highest it has been was 227F and i was fresh out of the car wash and sitting at a stop light waiting to go and even the oil temp was well over 200 F so my question is has anyone ever replaced theirs. how difficult is it and is it possible to do without taking apart the front end as i have seen some people say you have to remove the bumper and upper rad support
 

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SRT8
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Are you sure it's not the thermostat or Water Pump.

The Electric fans on these are pretty robust, and i haven't seen many failures on them.

But plenty of Water pumps and Thermostats on the 3.6.

others can chime in but the 3.6 Has a ton of space in the engine bay and the fan is located behind the radiator.

Typically if the A/C is on the Fan should be on aswell.
 

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Ummm, other than the vibration, what you describe sounds normal.

That is why you have an electric cooling fan, it doesn't turn on unless its needed. The two conditions that will turn it on is;

Coolant Temp reaches 225°F and it will turn off again once Coolant Temp drops below 203°F.

Air Condtioning Hi-Side Pressure goes above 110PSI and turn off when the pressure drops below 110PSI. For a good working AC, the Hi-Side will go over 110 PSI within seconds, or even less, of turning it on.

There is no reason why the fan should turn on as soon as you start the motor. If the motor is cold, the only reason I could imagine that would cause the fan to turn as soon as you start the motor is if you left the AC switched on, as soon as the motor starts turning it turns the compressor and the AC pressure will hit that 110PSI in a second.

Also keep in mind, FCA and many manufacturers have their HVAC setup that it will turn on the AC on low if you have Defrost/Defog selected. The AC dries the air and reduces it humidity, low humidity dry air is far more effective at defogging a window as it will evaporate the moisture collected on the glass much faster.

Those numbers are from memory, and it might be different for your V6, but they should be close.

Going 2°F above the threshold of the fan turn on point is perfectly normal, it would not worry me. 227°F temps are normal as well. If you've got air flowing through the radiator, like your driving forward, you should be seeing temps around 195-205°F, if its constantly at 227°F in all conditions, then yea, I suspect something might be wrong. But if you see temp climb up while the car is at a stand-still, until it hits 227°F and starts going down again as the fan comes on. That's normal.

Is the fan dirty, have built up crud on it? That could throw it off balance and cause vibration. Is it damaged and has a chunk out of it? That could throw it off balance also.

Also, 200°F oil temps don't sound that high either. Granted, temps have been in the 40's and 30's in my area, but I see 180°F oil temps all the time. I'm sure as soon as I get up in the 80's and 90's, maybe even the 70's and using AC, I'll be seeing oil temps of 200°F as well.
 

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Discussion Starter · #4 ·
I agree with what your saying but I always have my defrost on because it always fogs up and the fan doesn’t kick on as soon as I start the car it does turn on around 197 for me usually but I have got out and looked at the faneven when you feel that kick in and it doesn’t turn but maybe 1 inchbut I have never seen 227 on a 50degree day ever only at maybe9 90 I’ll look around still keep options open Incase it is at fault I can get it fixed for decent price or by my self if easy enough
 
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