Fort Smith, AR28 posts · joined Aug 20252021 F-150 XLT 5.0 SuperCrew, max tow
2021 XLT SuperCrew 4x4, 5.0, 3.55 with the max tow package, 10R80, 44,000 miles. pulling a 28 foot Jay Flight that scales at 7,800 loaded, on an Equal-i-zer hitch set up by a shop in Van Buren.
saturday the first, 101 degrees at 3 in the afternoon, because i am the kind of man who leaves when the truck is packed and not when it is smart. headed north out of Alma up the long grade toward Winslow. tow haul on, truck picked seventh, then sixth, held 62 and never felt strained. transmission temperature on the dash display climbed the whole way up and read 232 at the top. engine coolant sat at 221 and did not move.
no warning light, no message, no limp. but 232 is a number i have never seen in that truck and i have been pulling this trailer for two years. is that a problem, is that just august in arkansas, and is there anything i should be doing other than slowing down.
ford_tech_wendellHigh mileage#2
Toledo, OH64 posts · joined Aug 20252019 F-150 XLT 2.7 EcoBoost, 6.5 box
232 on a 6 percent grade at 101 ambient with 7,800 behind you is not a failure and it is not something i would lose sleep over. the number on your dash is sump temperature, and the truck does not start telling you about it until it is a long way past that. i have scanned trucks coming off I-75 in july hotter than yours with nothing wrong.
here is the part that matters though. fluid does not care about the warning threshold, it cares about hours. automatic transmission fluid life roughly halves for every 20 degrees you add above about 175. so a truck that lives at 232 on summer trips is using up its fluid several times faster than a commuter truck that never sees 180. that is not damage today, that is damage in 2029 at 110,000 miles when the fluid has turned brown and somebody blames the transmission.
what i would actually do:
leave tow haul on and leave it alone. it is holding gears and keeping the converter locked on purpose. fighting it with the paddle is how people make it hotter.
on a long climb, pick a gear manually and let the engine turn 3,200 instead of letting it hunt between two gears near the top of the grade. hunting is the heat.
go look at the front of your truck. a max tow F-150 has a stacked cooler up front and it fills with grasshoppers, cottonwood and the hay dust half of arkansas drives through. pull the grille cover off, wash it from the engine side out with a hose, not a 3,000 psi pressure washer, because you will fold the fins over and make it worse.
Mercon ULV, and if you tow every month i would not wait for the severe duty interval in the book. drop the pan, change the filter, do it around 60,000 and again at 120,000.
also check your trailer brake gain. a trailer that is not pulling its own weight down a grade makes the truck do everything, and the transmission is part of how a truck holds a trailer back.
ram_hemi_guyDaily driver#3
Baton Rouge, LA19 posts · joined Aug 20252020 Ram 1500 Big Horn 5.7 eTorque, crew cab
nothing around here is steeper than a levee so i had to go find a grade to have your problem. towed the boat to Gatlinburg in june, 5,200 lbs, and the 8 speed in mine sat between 218 and 226 climbing out of Newport with the air on.
the thing that dropped my numbers more than any part i could have bought was leaving at 6 in the morning. 78 degrees instead of 99 took about 15 degrees off the top of the climb, and the kids slept through the first two hours, which is worth more than 15 degrees.
and i will say the quiet part. everybody who posts about trans temps on the internet eventually buys a bigger cooler and then finds out their fluid never gets up to temperature in february. if the truck is not warning you, you have a driving habit, not a part problem.
fleet_manager_robTow rated#4
Bakersfield, CA31 posts · joined Aug 20252022 Silverado 1500 LT and a 2021 F-150 XL, fleet
our trucks pull equipment trailers over the Grapevine on I-5 most weeks of the year, which is five and a half miles of climb in 100 degree valley air, so this is the only thermal question i have real numbers on. half tons with 7,000 to 8,000 behind them land in the 225 to 240 range going up and come back down to 190 inside two miles on the other side. that is just what it is.
the part worth knowing when you are picking a trailer or a truck. the tow rating on the window sticker comes from a test procedure, J2807, that specifies the trailer, the grade and the ambient conditions. it is a real test and it is also a specific test, and it was not run with your 28 footer catching crosswind like a billboard. the standard is published by the engineering body at sae.org if you want to see what the conditions actually are.
my rule for the fleet is 80 percent of the rating for anything with an hour of climbing in it, and i care more about the frontal area of what we are pulling than the weight. a 6,000 lb flat trailer with a skid steer on it is easier work than a 6,000 lb travel trailer, every time, and the temperature gauge tells you so.
ecoboost_vs_coyoteOPTow rated#5
Fort Smith, AR28 posts · joined Aug 20252021 F-150 XLT 5.0 SuperCrew, max tow
ford_tech_wendell wrotego look at the front of your truck. a max tow F-150 has a stacked cooler up front and it fills with grasshoppers.
you were not kidding. pulled the grille and the front of that cooler stack was a solid crust of grasshopper and about four years of cottonwood. i could not see daylight through the bottom third of it. hose from the engine side, twenty minutes, and the driveway looked like a crime scene.
then i found the other half of it. trailer brake gain was set at 3.5. i have no memory of setting it at 3.5, and at that number the trailer was basically coasting into the back of the truck on every downgrade. put it at 6 and the whole rig feels different, and it stops in a way that does not make my wife grab the handle.
ran the same hill sunday, same trailer, left at 6:50 in the morning at 78 degrees, picked sixth by hand and let it sit at 3,100. peak was 214 and it was back under 190 before Fayetteville.
so: a dirty cooler, a brake controller i had set wrong, and the worst departure time in america. none of it was the transmission. filing the fluid change for this winter.
tonneau_cover_debateDaily driver#6
Duluth, MN22 posts · joined Aug 20252023 Sierra 1500 Elevation 2.7T, 5 ft 8 box
adding a small motor to the sample. 2.7 turbo Sierra, 5,400 lb boat and trailer, climbing Thompson Hill out of Duluth which is a short steep one instead of a long one. 215 to 220 at the top on an 80 degree day and that is with the four cylinder working harder than your V8 does.
the short steep grades do something different than the Grapevine. you get up it before the fluid has time to soak, and then you sit at the light at the top with no air moving through the cooler, and that is when my number keeps climbing for another half mile. so i do the dumbest trick there is, i keep it moving at the top instead of parking at the gas station right there.
ford_tech_wendellHigh mileage#7
Toledo, OH64 posts · joined Aug 20252019 F-150 XLT 2.7 EcoBoost, 6.5 box
good result and the brake gain being wrong is the common one, i see controllers set at 2 on trucks pulling 9,000 lbs all the time.
one closing note for whoever searches this in three years. if your temperature climbs like that with nothing on the hitch, that is a different conversation. empty and hot points at the thermostatic bypass valve in the cooler circuit sticking, or a line that got crimped when somebody pulled the front end apart for a radiator, or in a few cases a cooler that is plugged on the inside with the clutch material from a transmission that is already on its way out. empty and hot is worth a scan. loaded and hot in august is a tuesday.
and labor day weekend is the single worst traffic to be sitting in with a trailer, so if you are going anywhere, go thursday.
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