2017 Expedition XLT Overheating while Towing

[rnazer83]

I have a 2017 XLT with around 93,000 Miles on it. While towing a 6500 lb trailer (loaded) it gave me an Engine Coolant Over Temperature warning message followed by reducing power to the engine.

I noticed that this happens when i go over 65 mph. I am usually in Gear 6 at this point. When i am on cruise control it tends to keep it in gear 4 or 5 and i never got this message.

Reading through these forums, I see that it is recommended i drive in Tow/Haul mode, but I dont see this option anywhere. There is no button for it that I can see.

Any advice would be appreciated.

 

[GlennSullivan]

The Tow / Haul button is the round silver button on the shifter (facing the driver). The oval rocker button just above the Tow / Haul button is for transmission gear control.



Have you checked the coolant level? If not, do so.

 

[3rd Expyowner123]

My 2018 was getting hot when pulling my boat on the freeway at 70mph. Solution was replace thermostat. Ford dealer did not think that would fix the issue, commented that they do not replace many defective thermostats.
My truck on another occasion had water pump replaced. It was leaking with occasional drip while hot and running. Never did see the leak, dealer diagnosed after coolant was low.

 

[GeoPaw]

My 2017 Limited is also on the left-hand side of the shift control lever. A very small yellow message pops up on the dash “tow mode“.

 

[ediddily]

Try the cheap and simple things first.. like a flush and fill with new thermostat. Even a new reservoir cap, it may not be releasing the excess pressure. Other than that you'll have to consider the possibility that your water pump is going out or a radiator is slightly plugged. Recently I did a whole front cooling system replacement. I had a pinhole leak in the radiator plastic portion, as high as the reservoir, for ~10years. I had to run the car with the reservoir coolant cap loose to keep it depressurized and the fluid level as high as the pinhole. It just worked so I shrugged it off. Then the pump started weeping. So I broke down and replaced the water pump, radiator, hoses, thermostat, and reservoir cap. It starting working so well that the rear heater hoses started leaking and replaced those as well. Unfortunately the new reservoir hose failed slightly and weeps a drop now and again which I'll live with. But all in all it works great now.

 

[bodabdan]

Thermostat can be verified by putting it in hot water with a thermometer. Not real scientific but if you see it open fully it's probably working. Even if you just change it anyway you could still test it (even alongside the new one) just to know if you found the problem.
Also, your water pump is running at lower speeds in the higher gears. It makes sense that 6th gear would be the first to show cooling issues.
Make sure all air dams are in place and not moving around at highway speed.
Check radiator, condenser, and a the coolers for cleanliness.
Verify your coolant makeup is correct.
I've been working on stuff for a long time. When things don't make sense go back to the basics (as stated above) and assume nothing. Verify everything.