241 deg F Transmission Temp & Climbing

This is not the 1970s. These trucks are extremely well engineered. If the trans is getting too hot it's because it's being abused beyond it's engineered capabilities. Either slow down, or buy the 6.7 to pull the load that you're trying to pull at the speeds you're trying to pull said load. Adding a antiquated trans cooler to a truck like this ain't gonna fix it.
The 7.3 will NOT perform like a 6.7....period.....in any respect.
 
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This is not the 1970s. These trucks are extremely well engineered. If the trans is getting too hot it's because it's being abused beyond it's engineered capabilities. Either slow down, or buy the 6.7 to pull the load that you're trying to pull at the speeds you're trying to pull said load. Adding a antiquated trans cooler to a truck like this ain't gonna fix it.
The 7.3 will NOT perform like a 6.7....period.....in all respects.
I wasn't alive in the 1970s. I can send you pictures of all late model trucks with cooling system and Trans cooler upgrades. I didn't invent that. I'm well aware of what these trucks are made for and what they can do. I don't want to pull hills at 75 myself but I didn't ask the question. If the poster is really pulling the weight he says he is he shouldn't have any problem with a 7.3L. Technically an F-150 is rated higher than 10k these days. Thanks for trolling though. I'll continue to direct my comments to the person asking the question.
 
I wasn't alive in the 1970s. I can send you pictures of all late model trucks with cooling system and Trans cooler upgrades. I didn't invent that. I'm well aware of what these trucks are made for and what they can do. I don't want to pull hills at 75 myself but I didn't ask the question. If the poster is really pulling the weight he says he is he shouldn't have any problem with a 7.3L. Technically an F-150 is rated higher than 10k these days. Thanks for trolling though. I'll continue to direct my comments to the person asking the question.
LOL! Hardly trolling......some day you'll figure it out....maybe
 
It amazes me the amount of comments I see about the 7.3 not being capable enough. Correct me if I’m wrong but it’s the same 10 speed in the PS and the 7.3 right? Can someone confirm the trans cooler is different on the 6.7 trucks vs the 7.3? The 7.3 has plenty of power I know for sure it would out pull the 7.3 ps I put over 500k miles on with around 400k of them pulling a trailer. Hell when I was younger with less funds I used to pull 12k trailer up the mountains of NC with a 71 f350 dump bed with the 390FE and 4speed manual.

I’ve read other places that ford designed the 10 speed to run hotter for better efficiency and the trans fluid is designed for higher temps. I haven’t researched it enough to say that’s true or not but the OP’s truck never reduced power or had any warning lights that I’ve seen mentioned so it was fine to keep driving.

I’ve had many diesels and know they have their place and advantages but also know they have their weaknesses. Back in my past life running a communications company I had 2 6.4 psd trucks stand people due to the dpf sensors. One got so hot it welded the sensors in place and the dpf had to be replaced and wasn’t cheap. I don’t know about the 6.7 psd but the 6.4 would show a message saying pull over safely and would reduce you to 15 mph right after the message.

Kinda got off on a rant but my main point is the 7.3 is a very capable truck and from what I’ve read didn’t fail to do it’s job.
 
I have had my 7.3 Tremor since early of last year. Towing a 10K boat and trailer and a bed load of gear up and down steep grades in upstate NY both highway and on county roads. Just as 75FordMan said there is plenty of info about the 10 speed being designed to run hot. Have had no issues so far with the transmission, I think this is normal operating temps but I am sure a Duck Duck Go search could find that spec yourself. Quick search says Normal operating temp is 206-215 degrees F so I am sure going above that range is expected.
 
To the op, I recently did a trip from TX to AZ on I-40 and encounters a range of temps, elevations, grades, and winds while towing our boat. I estimate that I was pulling maybe around 7k boat and gear included and the truck did great. I ran about 68 mph (that’s what I was comfortable with) and found that if I locked out the top gears on the steeper grades the truck pulled them just fine. If I remember correctly I ran anywhere from 215-230 on the transmission temp when I would check. On most grades when I downshifted early the truck would pull anywhere from 2k-3k rpm, on a few steeper grades the engine would rev higher but those were pretty steep and shorter. At the end of the trip I was pretty surprised how well the truck did, so maybe try locking out the top gears first when you know you have a steep grade and see how that works for ya. I should add that I downshifted just before the grade to help the engine maintain speed and didn’t wait to shift until I began to lose momentum.
 
This is not the 1970s. These trucks are extremely well engineered. If the trans is getting too hot it's because it's being abused beyond it's engineered capabilities. Either slow down, or buy the 6.7 to pull the load that you're trying to pull at the speeds you're trying to pull said load. Adding a antiquated trans cooler to a truck like this ain't gonna fix it.
The 7.3 will NOT perform like a 6.7....period.....in any respect.
Was able to do 75 mph up the same hill with the same trailer with my 2017 F150 3.5L twin turbo Ecoboost with the new 10-speed that came out that year (same time of year at almost the exact same outside temperature). Yet I had no elevated transmission temperatures with that truck. Have no need to go back to the diesel world … been there done that … have previously owned a Powerstroke, a Cummins and a Duramax. The torque for pulling was great … but injector issues, DPF issues, DEF pump issues, rough shifting transmissions, limp mode, random & expensive warranty fixes, etc. … not a reliability confidence builder. Pulling 10,000 lbs. a dozen times a year didn’t pencil out to justify a diesel as a daily driver to work … which is why I chose the 7.3 w/ the 10-speed transmission. Guess I gotta be easier on my F250 Super Duty than my F150 Ecoboost when towing my travel trailer 😉.
 
Was able to do 75 mph up the same hill with the same trailer with my 2017 F150 3.5L twin turbo Ecoboost with the new 10-speed that came out that year (same time of year at almost the exact same outside temperature). Yet I had no elevated transmission temperatures with that truck. Have no need to go back to the diesel world … been there done that … have previously owned a Powerstroke, a Cummins and a Duramax. The torque for pulling was great … but injector issues, DPF issues, DEF pump issues, rough shifting transmissions, limp mode, random & expensive warranty fixes, etc. … not a reliability confidence builder. Pulling 10,000 lbs. a dozen times a year didn’t pencil out to justify a diesel as a daily driver to work … which is why I chose the 7.3 w/ the 10-speed transmission. Guess I gotta be easier on my F250 Super Duty than my F150 Ecoboost when towing my travel trailer 😉.
10R140 is not the 10R80. Can't compare like this in a meaningful manner.

And maybe don't let the Tremor shift cycle next time.

Ecoboost should hold lower gears longer to maintain boost.
 
10R140 is not the 10R80. Can't compare like this in a meaningful manner.

And maybe don't let the Tremor shift cycle next time.

Ecoboost should hold lower gears longer to maintain boost.
Tremor never shift cycled … simply downshifted as it should to 5th gear and held itself there until I crested the top of the hill.

Also formally documented the elevated transmission temperature with the local Ford dealer’s service department. Service manager said to continue using cruise control and if the transmission overheats (i.e trouble light comes on the dash), they will deal with it at that time. Gotta say I agree with the service manager … should not have to babysit a new transmission.
 
Dredging this thread back up. Towed up and over Loveland and Vail passes with my 2022 7.3 and my TT which was likely around 8500lbs and a huge brick (toy hauler). Trans did reach 240, 55 degrees ambient. I let the truck work, ran about 60mph and let the motor sing along at 5500 rpm, usually about 4th or 5th gear. IMHO, it’s the RPM’s the motor is spinning vs. the shifting or anything else.
 
I pulled about 7000lbs from Tooele to Green River and back again, Taking the route through Price and over Soldier Summit both times. Max trans temp was 212.

7.3l

I know it's not 10k, but lots of elevation change and I expected higher Temps.

I held 77MPH through most of the canyon, but at times was forced to slow for traffic.
 
I would like to understand what is to hot as well.
Towing heavy with a 7.3 on 6% grade the transmission can get warm I didn't switch over to the temperature for the transmission but could see it slowly climbing when pulling 18-20k. sardine canyon utah is the only place so far the temperatures start to climb @ "60mph 6% grade for maybe a mile".

Engine temperature doesn't move only transmission temperatures.
I pull a 2022 grand design 395m the 7.3 pulls it fine only issue is the transmission temps.
The dealership says just don't let it go in the red.. have they even seen how close the yellow and red markers are o.o
 
Attached is the Mercon LV transmission spec sheet - In all I have reviewed - 270 is the point at which your ATF will break down and you will at some point have a catastrophic failure. Once you hit 240 degrees you should be slowing down - if you hit 250 you need to take immediate action to allow it to cool down (slow down, but don't stop - you need to keep air flow to allow it to cool - if you stop, it will heat up more, before cooling).

Towing a 395M which is 15,400 lbs. unloaded with a 7.3 is a load for sure - and as you noted 18k-20k loaded - so you are working your truck hard on a 6% grade. In addition you are very close to the max tow rating for your truck (maybe over if you have an F-250). To maintain pace you are going to have to run high RPM in a lower gear - that will generate heat and at some point will require you to slow down.

Best plan is to mind you gauges, if you go over 240 take it easy until you cool a bit - always better to slow down and get there, then break down and waste the day (or two) sorting out the issues. In addition changing your ATF more often than the owners manual calls for is cheap insurance as well - gauge your changes off your towing miles, versus total miles - every 10k total and/or every 5,000 miles of towing whichever comes first - that of course if is you are towing a heavier trailer and seeing elevated temps - if not than that can be overkill - but far cheaper than the alternative.

Last if you have not already done so, have someone use Forscan and put the actual temperatures above your guages so you can see not only on the guage, but an actual number. Remember those are dummy guages - so a computer estimate of the tranny temp - so error on the side of caution!
 

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Attached is the Mercon LV transmission spec sheet - In all I have reviewed - 270 is the point at which your ATF will break down and you will at some point have a catastrophic failure. Once you hit 240 degrees you should be slowing down - if you hit 250 you need to take immediate action to allow it to cool down (slow down, but don't stop - you need to keep air flow to allow it to cool - if you stop, it will heat up more, before cooling).

Towing a 395M which is 15,400 lbs. unloaded with a 7.3 is a load for sure - and as you noted 18k-20k loaded - so you are working your truck hard on a 6% grade. In addition you are very close to the max tow rating for your truck (maybe over if you have an F-250). To maintain pace you are going to have to run high RPM in a lower gear - that will generate heat and at some point will require you to slow down.

Best plan is to mind you gauges, if you go over 240 take it easy until you cool a bit - always better to slow down and get there, then break down and waste the day (or two) sorting out the issues. In addition changing your ATF more often than the owners manual calls for is cheap insurance as well - gauge your changes off your towing miles, versus total miles - every 10k total and/or every 5,000 miles of towing whichever comes first - that of course if is you are towing a heavier trailer and seeing elevated temps - if not than that can be overkill - but far cheaper than the alternative.

Last if you have not already done so, have someone use Forscan and put the actual temperatures above your guages so you can see not only on the guage, but an actual number. Remember those are dummy guages - so a computer estimate of the tranny temp - so error on the side of caution!
At 240, the gauge is nowhere near the yellow/red. I’m guessing yellow is around 250 or so. The trans seems to get up to that 240 quick but doesn’t build much faster after that. My experience is the acceleration going uphill is what builds the heat.
 
Sorry ... been offline for a while (new job with extensive travel requirements - US & Canada). All 2020-2022 Super Duties have a known CDF clutch hub design issue where a sleeve inside the clutch hub bore rotates & moves down the bore blocking or partially blocking the fluid flow ports in the clutch hub. This is likely the issue with my transmission. It is at the local Ford dealer this week for a transmission inspection to hopefully determine the elevated transmission operating temperature when towing issue. Will update this posting regarding what they find. Below is the sticker on my 10R140 transmission showing the normal operating range for the transmission fluid. Sad part is I have pulled this exact same travel trailer with my 2017 & 2022 work F-150's with the 3.5L Ecoboost at the same speed and the transmission temperature stayed right around 210-215 degrees the entire time. Same mountain pass, same time of year, and almost the exact same outside temperature. And I have now also done the same exact same pull with my F250 Tremor (w/ 7.3) both with & without cruise control on (always in tow haul mode when towing) and it made absolutely no difference ... same 240 deg transmission fluid temperature.
 

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