Budocka

I wanted to see if anyone else was starting to experience the similar issues. Here is a little back ground.I have been towing a 7500lb travel trailer (loaded weight) up a pretty steep grade 4,600-7,100 ft elevation change over 10-12 miles. The first two years 2015-16 no issues at all. Made the pull at 60+ mph. No indications of engine temperature problems or triggering the temperature indicator at 235°F. Last fall I ended up in limp mode before I crested the hill. I thought it was the license plate mount which could have been blocking air flow. This was the only difference in the other pulls. So, I removed it. But when I made the trip this year I ended up at 248°F. I turned off the AC at 230°F and turned on the heater at 235°F. Still almost triggered limp mode. Below is the vehicle information.
Year: 2015
Model: F-150, 501 Package
Engine: 3.5L Eco Boost
Transmission: 6 Speed
Transmission Mode: Tow/Haul Mode
Rear end: 3.55
Mileage: 42,000
Ambient Temperature: 85-95°F
Max Tow Package
Same Trailer and same travel path.

Any thoughts on what is causing the temperature increase where it did not occur in the past?

Is it possible for a radiator start fouling out at 40k miles?

The other though I had was to remove the grill and pressure wash the radiator to remove all of the bugs that have built up over the past couple years. To see if it was impacting the heat dissipation on radiator.

Thanks for your input.

BadBoy4fun_wa

There is another thread where someone was having the exact same problem with an almost new truck. In the end the solution was the Radiator. It definitely is worth checking to see if you have blockage but his was the radiator itself. His was just fine until he towed. For a while they tried to blame the trailer but his older non Max Tow was fine for years same conditions.

BCMIF150

My first thought would be a dragging trailer brake. How do you know it almost triggered limp mode?

Budocka

Update - it was actually power down mode due to temperature. Once you go over 225 degrees Fahrenheit a numeric read out of the temperature displays above the digital gauge (8" cluster screen). Power down occurs around 250 F. Where it shuts off the turbos to cool the engine temperature. So I can tell I was almost to the point of power down. The way I was able to keep it form going to power down was to turn the heat to max and roll down the windows. This should not be the standard operating conditions for this truck.

I don't think it is hanging trailer brakes, because the first time it occurred last year labor day(2017). I had all the axel bearings repacked this spring (2018) and I'm sure it the were hanging the dealer would have hit me up for a repair.

The Ford dealer replaced the radiator and fan a few weeks ago to see if the would solve the problem. Which it did not. When I brought my trailer home from Bear Lake on Labor day (It was stored there for a couple of weeks) I had the temperature rise it out of the canyon. So I confirmed it yester day by towing it up Parleys Canyon and the temp started to rise before I got to hard portion of the pull the ambient temperature was actually lower by 5 degrees then when I would normally pull. I have used the truck to pull the same trailer sense it was new same time of year and temperature conditions.

I went and scaled the truck and trailer yesterday to confirm I was with in specs and here is what the weights were:
Front Axel 2,980 lbs
Rear Axel 4,300 lbs
Trailer Axel 6,280 lbs
Total GWCR 13,560 lbs
Which equates to 79.7% of the combined 17,000 GWCR that the truck should handle.

UncleG

Is the tranny getting hot ? Might need an extra tranny cooler.

tvsjr

I'd be concerned about trailer brakes and the cooling system. A good coolant flush might be useful.

Also, if you have the 8 inch screen, you can use Forscan to enable those temperature values full time. That might give you some more ideas.

Budocka

Going to call the dealer today and see what the next steps are. Going to push replacement of the water pump and thermostat. I'm pretty sure it is not the trailer because it is only 6 years old and just had the bearings repacked 6 months ago. But I'll rule it out by towing my friends which is about a 1000 lbs lighter and a year old.

The one thing I noticed on last weekend trouble shooting exercise was once the trans down shifted to 2nd and the RPM's went up to 5500. The temperature dropped below the 225 F mark which and turned off the numeric value. But I'm pretty sure I should not have to red-line all the time to make it over a hill without high temperatures.

I have not had any indications of high transmission temperatures. I had the readouts enabled utilizing FORscan and the max trans temp was 215-220F. Seem pretty reasonable and dropped right back to 205 once I completed the pull.

I removed the numeric gauges because I didn't know if it would stop the computer from reading a temp trigger once it would kick on the gauge.

GoingGonzo

Another option to try, to rule out the trailer itself, is a trailer TPMS:

https://www.minderresearch.com/tirem...-for-trailers/

If there's an issue with your trailer wheels, whether it's brakes or hubs, etc, it should heat up the tire enough for the TPMS to alert you. If the trailer pressure and temps are normal after towing for a while, but your engine is overheating, then that should rule out a dragging trailer as the source of your problems.

Gonzo

tcp2

2015s have shutters on the grill. If they aren't reacting properly to inputs, you could have an overheating condition. Maybe try it with them unplugged (and confirm they are at maximum open position).

Budocka

I have been considering TPMS for the trailer. Guess this gives a good justification for picking them up. I'll post what happens on the louvers.

Update - installed the CarChet TPMS system on the trailer because the TireMinder solar unit would not work due to the length of the trailer. Pressure only increased 3-5 psi and the temperature went up about 10 degrees. None of the tires were significantly off from the others. So I can safely check the trailer off the list of possible causes.

Made the same pull that I normally would because it is only 45-60 minute round trip. I did have the temp indicator come on but with ambient at 72F and the trans down shifted to 3rd bringing the RPM up to 3500 it quickly cooled off. so was able to make the entire pull with out going into power down mode.