Transmission Temps Seem High

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We just bought a 2019 Expedition Max 2WD without the HD tow package. Cruising down the highway with no trailer behind me, I was seeing trans temps upwards of 213º F. That seems awfully high to me, especially considering we plan to haul a 4,400 lb travel trailer from Texas to Colorado in a few months.

I've read thru the forums and have seen a somewhat recurring theme about high trans temps, but they usually include towing.

I also can't definitively determine if there is a trans cooler with the XLT (202A package) or not. I've seen some people post about potentially adding one, but has anyone successfully done it yet and if so, do you have a model of cooler you recommend?
 

Dice Roll

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Mine runs hot too. 205-208 was common when it was colder out. Haven’t paid attention in the few miles I’ve driven since it got warmer. Mines a 2wd also.
 

st381183

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I’ve always thought these trannies ran hot. Southern NM, summer temps are 99-105 degrees, transmission routinely in the 208-215 degree range. No towing. Service rep said that was normal. My 99 Silverado runs about 190 degrees but it’s also not a ten speed transmission.
 

aggiegrad05

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You might look here as well; although it looks to have gone about the same way this one did (haha)

https://www.expeditionforum.com/threads/transmission-temps.35576/

As far as a trans cooler goes, there is “active debate” on here about whether these vehicles have one because the previous gens did. Does it come standard? Does the HD Tow pack give you one? Is it integrated into the beefier radiator? My suspicion is: these new 10 speed trannies either all have one, or don’t need it. But we’ve yet to collectively figure it out.
 

wakeboarder

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According to the thread below, the transmission cooler is a liquid to liquid heat exchanger. It most likely uses the same coolant as the engine to cool the transmission oil. This is an extra step from most older systems that used a air to oil heat exchanger. This is probably on reason why it runs a little warmer. Maybe one of the benefits of this type of system is that it would actually use the engine coolant to warm up the transmission faster in colder environments.

https://www.expeditionforum.com/threads/towing-capacities.43649/page-2
 

JExpedition07

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If the 10R80 is like the 6R80 the flow of fluid to the cooler will be thermostatically controlled, the 6R80 won’t open flow and send fluid up to the auxiliary cooler until 190 degrees is hit. Since the 6R80 and 10R80 are VERY similar besides number of gears, I’d say this is normal and you also likely run a thermostat. They keep making these things run hotter and hotter for efficiency and emissions just like the engines. Engines used to run at 160 and now many run over 200, better metallurgy and meeting newer efficiency standards.
 

ETC13

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The 10R80 also use a specially developed transmission fluid for the higher temp that it is designed to operate at.

Mercon ULV

The fluid specification for Mercon-ULV (Ultra-Low Viscosity) was introduced on January 2, 2014. Mercon ULV is composed of a Group 3+ Base oil and additives needed for the proper operation of the 2017 and above Ford 10R80 and the GM 10L90 10-Speed rear wheel drive automatic transmission.

This transmission and the transmission fluid specification was co-developed by Ford and GM. The current specification that defines the fluid is FORD WSS-M2C949-A.[10] This fluid is also marketed as Dexron ULV.

NOTICE: The quart containers of Mercon ULV must be shaken to stir up the additives before pouring. This fluid is not backward compatible with any previous fluids.

This fluid was first used in the following transmissions:

2017 10R80 10-speed automatic transmission

2017 6F15 6-speed automatic transaxle

2017 6R100 6-speed automatic transmission



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Greg Parker

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Kinda reviving an older thread here. I recently towed my 6200# GVWR camper for the first time with my new (holdover) 2019 Limited 4WD (with HD towing package). Here's a couple of thoughts...but I would also love it if a "Bob the oil guy" type of person was able to chime-in about the Mercron ULV longevity. I used to flush my Allison transmission in my Duramax every two years, but everything I'm reading claims that the 10R80 has "lifetime fluid" in it. Really?

  • Unloaded, NOT towing, my experience with all kinds of different rigs is that transmission fluid temps will generally run 100F-110F over outside ambient air temperature.
  • When towing, that usually bumps to 115-125F over outside ambient air temperature.
  • My Duramax / Allison 6-speed wouldn't balk one bit at close to 250F fluid temps. I have to assume that with all of the tech in the 10R80, that is probably the upper, safe-limit of it as well.
  • I got my rig upto 246F once climbing a very steep, long grade this past weekend. No alarms...no ding, ding, dings...but I was pretty nervous as I watched the blue bar eek closer to that first yellow ticker on the gauge (I had the main display showing me the "real temp" output...and that's how I read the 246F). I was running 55mph up that grade and it was 107F outside (according to the dash ambient temp reading). I'll probably slow my speeds next time to 40-45mph and see what kind of difference that makes (or slower...safer to just stay behind that slow semi than to punch it to make a low-gear 45mph pass).
  • On mild-to-flat grades, my fluid temps ran 215-220F.
  • I would love to treat this Expy just like I did my Duramax/Allison and leverage the "replacement method" to flush the system / try to get as much new fluid in the transmission as possible (every 2 years). Does anyone have any experience with this? Are we really going to trust Ford when they say the trans fluid never needs to be changed for the life of the rig?
  • Does the transmission have a spin-on external filter that is easily replaceable?
  • This "special" blend (Mercron ULV) is definitely new to me. Is it REALLY the best trans fluid for the 10R80?....or would a Redline, Amsoil, or other full synthetic be better?

I plan on going back through my owner's manual / towing guide and see what kind of recommendations & guidelines I can find. While I was pretty happy with the way my Expy towed my camper this past weekend, I am a little alarmed that I am barely over 66% max towing capacity / weight and STILL ran very close to max trans fluid temps. Yeah...it's hot here in AZ, but the summertime is when we do the most camping here (outside of hunting season in October / November). Hope I didn't make a mistake letting go of my old, tough Duramax / Allison. I had actually hoped to get a slightly larger camper next year, but not sure I'd be comfortable towing beyond 6500# with this rig. Love the Expy (a LOT) ...but a little disappointed in the 10-speed cooling capabilities. I reckon one has to be willing to drive VERY slow up the serious grades.
 

Expedition Dave

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2020 FX4/HD Tow/10 spd here.

Since the begining-breakin, my trans-temps never saw over 203F whether unloaded or loaded on the highway (about 3500lbs of people, goods and trailer) in 80-90 degree weather at Texas speedlimits. I expected to see it go up, but it did not (maybe saw 205F a few times)?

From my brief research (and general knowledge), I *believe* the trans can see 250+ degrees routinely and safely, while others say even higher (but only briefly and at a long term loss of fluid lubricity).

I for one under max-tow trans-overheating conditions would also think Ford's many little CPU brains would make it go into "limp-home" if your trans hit a point high enough to do damage.

If I towed HEAVY all the time and saw 250+F I might be concerned enough to find a way to get more air to the trans cooler, or bolt on a larger one. I also think heat travels downwind, so I'd look at fixing coolant temps too?

I already wish my hood had a electronic flap so I could vent under high heat, as I do tend to idle sometimes with the air on and it bugs my "sense of the way things should be," lol.

YMMV
 
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