248 engine oil isn't terribly hot for todays oils quite frankly , my 850s in my cig run 260 after a good hard pull on the sticks, 6100 for a few miles . these temps are red in the pan before the cooler , ive seen 270 more than a few times , bearings always look like new, every fall when I pull the main caps .. just saying

 

Hi Tyler, sorry to hear this as I was hoping I was the only one.

Most here don't have this issue, and I actually don't either except for that one trip out West with extremely high elevation grade climbs with outside ambient's reaching near 100*F.

I've also pulled down in (and through) the Great Smoky Mtns with not even a hint of warnings. Cooler temps and not nearly those killer out West grades. Hmmm. Well, I have a planned trip there again the 1st of May, so we'll see again very soon.

My fan (clutch) is definitely kicking in, but as you said, it may be doing it a tad too late. I'm going from memory like 7 Mos. ago of course, but I did hear the additional noise that the fan makes when kicking in and it did seem like it was very close to the over-heating indicator coming on. As far as gear dropping goes, in my instances of limp mode, my gears were dropped quickly and automatically to low gears, like 3rd gear on some grades. The engine was winding away well before any overheat warnings or the eventual limp mode ordeal. So gear dropping w the tranny was excellent and early enough. I was in 'Tow Mode' of course which drops gears much more quicker than normal mode.

So maybe you hit the nail on the head with the fan not kicking in soon enough!?!?!?!?!

Hopefully Ford will address this matter. If you start a letter to address this, count me in on endorsing it w you.

 

 

Having this switch would be helpful, yes.
But I don't see Ford doing that. How about a simple software (reflash) that would kick-in this fan clutch sooner when in Tow Mode?

I also understand the theory of not wanting this, as the fan-on when kicked in does (and is factually reported as) more in-efficient (fuel wise). But how about just in Tow Mode?.... for us heavy towers, that just may be the answer. TBC.......

 

1. Water wetter is a surfactant, (soap) and reduces surface tension of the water. I believe it is a very marginal improvement, if any. And I don't know if it might promote cavitation erosion in a diesel.
2. At high elevation, the mass airflow through the radiator is reduced, so you transfer less BTU's for a given temperature delta.
3. Living and racing moto at 7,000' elevation (plus up to 13,000' and down near sea level) along with having been towing heavy for 3+ decades, I have learned that the greatest challenge to cooling is at high elevation, slow speeds, heavy loads..... and ambient air temperature is not a large factor.
4. While I have abandoned modern diesels, I did encounter, once, the Ford overtemp, reduced power mode, while towing close to my max GCWR at 10,000+ feet elevation in Colorado while at WOT for 25 minutes up a 10% grade with the engine running at 6,000 rpm on my 6.2L 2011 F350.
5. I keep my vehicles completely stock, both engine ECM programming and no modifications to the front end that could inhibit airflow.

So, I would encourage you to:
1) Clean the AC condenser and radiator fins really well without damaging them. Including back blowing the radiator and condenser from the fan side with high pressure air and water. This was the cause of my overheat as mentioned in #4 above. I have never had an issue since this original problem over 100,000 miles ago. I now regularly clean my radiator and condenser and PS cooler.
2) Insure you don't have a problem with your cooling system as mentioned above, rad caps, thermostat, constricted hoses,....
3) If you are headed in to tough cooling conditions, turn off the A/C, enjoy the outdoors for a bit of the climb. And if you are still overheating, crank the inside heat up and use the heater core as auxiliary cooling capacity. Tell your occupants that you are training for Bickram hot yoga!

Cheers!

 

I wonder if it could be water pump related?
A few of us have had ours replaced, but the general symptom was leaking coolant, not necessarily temp warnings.

 

I agree that setting the cabin heater to max can help rapidly lower coolant temp in an overheat situation. I also endorse cleaning your radiators, etc...but on a 2017 truck this is not likely to be the problem unless you drive through cornfields with your truck or something similar.

Ford has tested and retested, including the Davis Dam run in 100F weather. The fan is electronically clutched, and designed to stay off for as long as possible to reduce fuel consumption and maximize available horsepower. However, when fully engaged it should be capable of providing enough cooling capacity even if it comes on "late."

The engine has several strategies to overcome an overheat situation. I believe the A/C will automatically shut down when coolant temp approaches overheating; the transmission will drop to a lower gear both to reduce effort needed to move the load uphill and increase the RPM of the water pumps. Fueling strategy is also key; significantly more fuel should be used to lower cylinder temps. An active regeneration would actually help reduce cylinder temps thanks to fuel being injected but not compressed.

My take is that if you are towing within your rated limits the truck should handle it without issue. If it doesn't, something is wrong with your truck.

 

 

You may have missed it, but mine downshifts soon enough (especially in TM), climbing a few of those steep grades in 3rd gear at 3+K RMP's easily.

It's not about lugging and low RPM's, when in Tow Mode especially.

 

Could just be a bad sensor.

 

Ignoring speed, towed weight and gear selection, what temperature is too high? Member Fountain 1 suggested (above) that 248° F isn't terribly high for the engine oil. Modern synthetic oils can likely handle this without an issue. But at what point will the truck de-rate or go into limp mode?

My truck's engine oil hit 243° F (as I recall) without exhibiting a problem (no warnings or de-rate). This was on a pass that peaks at 11,306' while I was towing somewhere between 10k and 11K.

 

 

I'd like to see any videos or written comparisons where the other two brands powered heavy loads up hills without issue but the Ford had issues. I can think of the "Midnight Super IKE" that TFL did when the 2017 trucks were just coming out. They ran a 450 up the Eisenhower Pass towing 30k lbs; then they subsequently ran a RAM 3500 towing 30k lbs. The Ford was a full minute quicker up the hill. GM doesn't currently have any trucks rated to pull 30k.

In hot weather, Ford should actually have the advantage...because it uses an air-to-liquid intercooler while GM and RAM use air-to-air. So Ford is able to actually maintain the charged air temp to about the same as always in 100F weather, whereas GM and RAM would be seeing noticeably warmed charged air temps in 100F weather...reducing horsepower and torque.

Just my opinion.