Hey guys
i have 2015 f150 5.0. My issue has just started come months ago. When towing 7000lb box trailer on inter state my transmission temp started climb ( i was going 80mph on an 85 degree day) close to yellow. I just realized recently there was a digital gauge do i don't know what exact temp was. I slowed down and it dropped back to normal figured i was just pushing to hard on hot day. So i have been watching it and temp is normal when empty running around. Then yesterday towering said trailer going 80 again it started to climb again only this temp outside temp was 37 so i figured something is up. Went to garage they checked fluid it looks good and is full. No slippage no noises just temp issue. I was wondering if possibly the radiator damper isn't opening like it should and that is stopping air flow enough to cooler to create this or what could it be. Any help would be awesome

 

What were the actual temps? What is the frontal area of the box trailer? Going 80mph with a 7000lb box type trailer is a tougher load then you think depending on the frontal area (wind resistance). How is your truck configured? Does it have the auxiliary transmission cooler like you'd get with the max tow package?

 

I don't know actual temps i just realized recently that it had that feature and haven't towed with it since. I have tranny cooler it's a crew cab 5.0 with 3.73 gears stock tire size. It pushed the gauge to the yellow before i backed off of it. The part that has me concerned is my father has i identical truck other than paint and his had never done this he totes it everyday i tow it occasionally

 

Does he tow the same trailer as you, loaded the same way as you? Towing load is a function of weight, rolling resistance, and wind resistance. Weight is the easy one and what people usually get hung up on, but another huge factor is wind resistance. Imagine towing a streamlined torpedo vs an opened ship sail...which one will glide through the air easier? At highway speeds on level ground, wind resistance is by far a bigger factor on overall load then weight, and a box trailer is perhaps the least aerodynamic thing you can tow. You are attempting to tow a 7000lb wind sail down the highway at 80mph, there is going to be a good deal of heat generated and your predicament is not indicative of an issue with your truck. Try lowering the speeds down 10mph and see what happens.

 

It's our trailer we use for electric work same tools same load if anything his is bit heavier because we have 3 guys in his truck and just 2 in mine. Ive towed this same trailer for three years no incidents. Just in last 4 months has this become an issue

 

I'll say what others are thinking!!!!
He probably dosen't tow @ 80mph either.....just my 2 cents & thoughts but that is getting excessive for any trailer!!
I want to see the video when you crash.........I'll betting it will be spectacular....Do you think!!

 

I'll say what others are thinking!!
He probably dosen't tow @ 80mph either.....just my 2 cents & thoughts but that is getting excessive for any trailer!!
I want to see the video when you crash.........I'm betting it will be spectacular....Do you think!!

 

i came here hoping to get an answer on what could cause this. Keep your 2 cents. I drive 80mph on interstate. Either help with the question at hand or don't respond.

 

Hey OP, you should start by enabling the digital temperature readout on your gauges via FORScan. MUCH better than guessing what it is, based on a graph gauge. Since your truck is a V8, it can't have the MaxTow package, which includes a larger coolant and engine oil radiators, and a transmission cooler. I just came back from Austin last Saturday, which was super windy (head wind, to make matters worse), and my truck was struggling a little to keep 80/85 mph. Had to downshift to 8th most of the time. It was cool, so temps were like always (engine at 205, tranny at 199). Got 15 MPG average for the 600-mile trip. My worst ever. And only the 2 of us, weighing less than 300 lbs combined. Going that speed with a tall and heavy trailer puts a HUGE strain on the entire drivetrain, so it's entirely possible there's nothing wrong with your truck, especially without the extra cooling mine has. You just have to take it easier when towing that much. Or install aftermarket additional coolers if you want to tow that fast. I'd also change your fluids a lot sooner than recommended with that kind of life. Good luck.

 

So why would it start doing this while other truck with same trailer is not doing it. i have a transmission cooler this truck had pulled this trailer for three years any and all weather conditions 2-3hr trips both truck make these trip with this trailer and one does it and other doesn't. All im simply asking is could the radiator louver not opening cause this or not.