2017 Expedition EL Overheating while towing

The last thing you did was the t-stat. It may be defective and not opening fully.

I've not experienced overheating with my '17 towing a ~6000 pound travel trailer. HD Tow and 3.31 axles. Mountains in both Virginias, both Carolinas, and Pennsylvania ain't the Rockies though.

I suspect you're overloaded in both towing and cargo capacity of the Expedition.

7000 full, 6300 dry.

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Have you weighted this trailer? I can put nearly 1000 pounds of stuff in my former popup camper so only 700 pounds seems light. 30 gallons of fresh water (250 pounds), a pair of 20 pound LP tanks -- which when full weigh 40 pounds each (80 pounds), a couple of deep cycle batteries (150 pounds) adds roughly 500 pounds to the trailer before the first bit of cargo gets in there. I'd expect closer to 9000 pounds for a 33' travel trailer.

Assuming you're really only 7000 pounds for a 33' trailer you have at least 700 pounds on the ball (not counting the weight of your WDH) and the cargo capacity of my Expedition is a small dog over 1400 pounds so there's no more than 700 pounds max for human passengers and stuff.

-- Chuck

If you had no Issues towing the same trailer before the belt break and overheat, the focus needs to be on that event, not on upgrading equipment. Your problem is somehow related to that event, or something that was done during the repairs done to fix it.

Incorrect or defective replacement / new thermostat. I would change thermo again and confirm the correct part number. Some folks on here are talking about updated stats for expys.

Fans not running properly, either speeds or not starting at correct temps.

The water pump is a possibility, not probable, but possible.

skamerick said:

it seriously overheated and just shut down. I had no idea on earth what happened, I thought I might have blown the engine. Had it towed to nearest Ford dealership and back on the road the next day.

When we got home, out of an abundance of caution, I had the cooling system flushed and the thermostat replaced. Now, when I drive (without towing anything) up the slightest incline the temp starts to climb. The oil temp and trans temp are fine. I've had it looked at by 3 different shops and no one has an answer.

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Chasing these symptoms can often lead down an expensive rabbit hole with a parts cannon, but there are a few things I always check after an overheating episode to rule out some preliminary issues.

First, I check to make sure the cooling fans are functioning properly when the vehicle is parked and idling - they should come alive to move enough air across the radiator to bring coolant temperatures down before going to sleep again. If they're not you'll want to check their associated fuses, relays, and wired connections. If the fans are working as expected, I'd next check for combustion gasses in the cooling system with a combustion leak detector kit. Overheating can sometimes compromise a headgasket which will lead to coolant consumption and gradual air pockets, and this can be checked with an inexpensive combustion gas detector. If you don't detect any combustion gasses, I'd move next into checking for pesky air pockets from when they had the system open to replace the thermostat. Park on a slight incline and turn on the defroster with the heat on full blast, as well as the rear heat. Bring the engine up to operating temperature and once the cooling fans turn on, bring the engine up to 3-4k RPMS for a few minutes to get the water pump moving and hopefully purge any air bubbles up to the coolant reservoir. If the coolant level drops after this, more than likely there was air that escaped from the system, so you'll want to top off the reservoir to the fill line and repeat this process a few times. If after these steps you're still experiencing overheating issues during normal driving, I'd suspect a defective thermostat and would request them to replace it under warranty (getting a ford OE thermostat would be a plus to rule out cheap parts), and request them to vacuum fill the system to again rule out any pesky air pockets after the new thermostat installation.

If you're STILL experiencing overheating after all of those steps, then you could begin to dig a little deeper. But I would rule out the above conditions before ordering aftermarket radiators, cooling fans, etc.

one other thing, on my 17, the manifolds warped and sheared the rear studs off. that could be the combustion gasses. piss poor design if you look at it. 3 studs for the front two ports and 2 on the elongated rear portion that goes to the turbos.

@skamerick I've looked but I don't see where you've listed the mileage of the Expy? The reason I ask, is the same as another poster, water pumps die on most cars around 100K. It was either on this forum or on Fordtechmakuloco (YouTube) where a picture of the original water pump's plastic fins were shown as sheared off - the fins on the replacement water pump from Autozone or wherever were metal. So your thermostat might be doing its job without any leaks but if the plastic fins aren't pushing the water around to cool the engine - that could be the source of your problem.
https://www.youtube.com/watch?v=QfO5hFN1NHw is a pretty good 'how to' video though I'd probably aim a camera into the engine bay so I could go back a step.

skamerick said:

My 2017 EL with the HD towing package is overheating while towing uphill. I slow down (less than 60 mph), and turn off the A/C to keep it from hitting the max heat level. I've flushed the cooling system and changed the thermostat. Does anyone else have an issued with engine temp going up while climbing?

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I have the same issue on mine. my trailer is 5200 ULW, so probadly 7500 loaded without water. Live in Northern California, so whenever I go to the sierras, its a non stop overheat fest.

Guipo said:

I have the same issue on mine. my trailer is 5200 ULW, so probadly 7500 loaded without water. Live in Northern California, so whenever I go to the sierras, its a non stop overheat fest.

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Year and milage?

After reading this post I can’t help but think your belt broke when a water pump fin broke and wedged against other fins causing it to temporarily lock up causing the belt to fail. Once the belt broke, the pump pulley was free to spin in the opposite direction to un-jamb any existing impeller fins that are left, then the broken debris sunk and settled somewhere in the system. If this is the case then your fin depleted pump is the reason you are overheating because of the lack of flow. I would have to put a new water pump on and flush the system regardless just to rule out this theory.

I installed my Ultra-Guage so I can montior the engine temp and turbo PSI. When the engine temp read 230 I drop down to a lower gear, which increases the RPMs, and I can watch the engine temp drop. I have successfully managed the engine temp this way while towing up hill. After doing some extensive research on the turbo engine, I found that they create termendous heat, which I wish Ford had addressed in the owners manual.