High milage service Question

[UstonXpedition]

Recently picked up a 2019 Expedition with 134k miles. Test driving and everything was fine at the stealer ship. Engine and transmission drives and shifts fine. The trans temp concerns me. 96f outside temp trans gets up to 220f. Then while we were towing a boat it went to 242f. engine temp was fine though. The odd thing is the coolant cap has been replaced with a motorad 21psi and seems to me the coolant is just distilled water in it. Plan to flush coolant and upgrade thermostat to 180f RT1258 or spd 180f. Will also be doing a PPE deep trans pan with the service kit. Hopefully That will bring the temp down. If worst comes to worst Im going to upgrade radiator and do aftermarket Air trans cooler. I think the fan based trans cooler maybe to much for my setup.

Need some insight:
1. Do I need a tuner to run the 180f thermostat? She is completely stock. if so can forscan configure the setting to change the temp switch?
2. Will it be safe on the transmission to drop pan/ and fill new fluid. (Not doing a Flush)

All in All She pulls great no problem but the trans temp. But this is my 1st 10r80 I've ever driven. She drives smoother then the wifes explorer and rides better then my f-250. Thanks in advance for whatever advice you can render me with.

 

[Going_Going_Gone]

Can you ask the dealership where you made your purchase to run an Oasis report on this vehicle. I believe it will show all work performed at dealerships: warranty, service frequency etc. You might find out if the original thermostat is still there.

 

[UstonXpedition]

Can you ask the dealership where you made your purchase to run an Oasis report on this vehicle. I believe it will show all work performed at dealerships: warranty, service frequency etc. You might find out if the original thermostat is still there.

I will try that. Thank you.

 

[UstonXpedition]

This what I'm getting 95* outside temp in houston. Not towing

 

[BigOleFordFan]

I know it's a different vehicle, but my wife's 17 Acadia w/a 3.6L V6 routinely runs a trans temp of ~160-180f under normal driving and 80-90F outside, and no towing either...

And normally, I think that as long as the indicator does not go past the 1/2 way point on the dial, which would start to be in the yellow (caution) section, you should be ok..same with the coolant temp & oil pressure

 

[SyndicateZ]

2019 limited stealth 4x4 HD Tow

My trans temps runs regularly between 208-212 regular city driving at about 80 degree weather. On the highway it ranges anywhere from 212 to 218. Im all stock with 76k miles

Also- on 2 seperate occasions, my engine temp guage gave me a high temp warning while passing a vehicle on highway while accelerating at about 80mph. As soon as I let off the gas and coasted the warning went away..I think I may need the "upgraded" thermostat as well?

 

[SyndicateZ]

This what I'm getting 95* outside temp in houston. Not towing View attachment 82450

That trans temp seems high compared to mines

 

[UstonXpedition]

That trans temp seems high compared to mines

I think it is. Its worst when we are towing a 3k lb boat. Transmission hit 240* (yellow line) just moving the boat from storage to the house 15mins away. No highway. I looked at the coolant and it look like the previous owner only had water in it with motorad cap. And the radiator looks like its been replaced with mahle. I GUESS THE DEALERSHIP NEVER LOOKED. But it drove fine during test drive.
I'm really thinking it's most likely the coolant wasn't bleed right/ water only. I'm going to do the flush and o.e coolant with the spd 170* and see if it changes the flow and temp. If the pan and the coolant and thermostat doesn't do the trick. I'm going to delete the h/x and do a external air cool trans cooler. Might do the universal mishismoto with fan and install at inline thermal switch. I've ran a generic transcooler with no fan on some of my old cars and they end up running 15-20* cooler.

 

[chuck s]

2017 XLT w/HD tow. My sample of one (1):

I was deliberately watching the transmission temperature during the 100°/100% weather we had in Virginia this August and it never exceeded 210° even when towing our 6000# travel trailer at Interstate speeds with the AC on.

-- Chuck

 

[NSRacer]

AZ Expy here - trans typically runs in the 210º range day to day. I've only towed with it once and I touched on 230ish degrees, but that tow was up to the high country (almost 6k ftt in elevation change) - roughly 3,500 pounds. I don't have the tow package either. I always felt the trans ran warm on this thing, but it's got 115k on it and, other than the occasional shift clunk, it's been fine...

 

[Going_Going_Gone]

Took a road trip from Phoenix to Breckenridge Colorado in mid July. Not pulling a trailer, but pretty loaded down. In preparation for this trip I had the thermostat upgraded, the cooling system flushed, and new coolant added; so I was curious as to how hot the transmission would run. Periodic checking showed the transmission running around 195° pretty much every time I checked with it only going over 200° climbing up from Camp Verde and a couple times after getting on it in passing lanes in northern AZ where I never saw temps that exceeded 210°. Knock on wood, still runs great.

 

[LG_123]

I tow an 8,000# travel trailer in heat like that and through the mountains and my transmission almost never gets above 220F unless it’s revving high with the engine brakes on a descent or chugging up a lengthy climb. Your temp is starting to sound concerning. I’m only at 65,000 miles on a 2019 Expy max platinum with HD tow.

 

[titanhoon]

I tow a 7k trailer through the Rockies all the time with my 2018 Max with tow package. My trans used to hit 240 doing some of the high elevation passes. The issue is the trans doesn't have an air cooler. Instead, the trans is cooled by a heat exchanger that is connected to the engine coolant. So if the engine is at 215 then the trans can't really go much cooler than that. Once the engine temps start going up so do the trans temps. It's a great system for getting the trans up to temp quickly but it's terrible for towing.

I bought a mishimoto trans cooler for a Raptor and a 190 degree temp inline thermostat. The cooler was a direct fit in front of the engine radiator. I disconnected the stock cooler and just use the raptor cooler. My trans temps never go above 200 now even when I was going through passes in Arizona in 105 degree weather.

 

[UstonXpedition]

AZ Expy here - trans typically runs in the 210º range day to day. I've only towed with it once and I touched on 230ish degrees, but that tow was up to the high country (almost 6k ftt in elevation change) - roughly 3,500 pounds. I don't have the tow package either. I always felt the trans ran warm on this thing, but it's got 115k on it and, other than the occasional shift clunk, it's been fine...

This sounds good. But why throw a 190 inline temp sensor? Did you add a fan to the transcooler? My original plan was to get the pro touring 10r80 manifold with the coolant temp switch and the mishimoto universal transcoolar with fan. But I want to do a deep ppe and drop the coolant temp so I'm going to do the 170 spd and see if I can drop it down more so the h/x can cool up quicker. But if it's still bad I'm going the other route.

 

[chuck s]

No transmission cooler on the 2018+ models? Just curious 'cuz my '07 and '17 had/have them standard and HD Tow has bigger ones.

-- Chuck

 

[titanhoon]

This sounds good. But why throw a 190 inline temp sensor? Did you add a fan to the transcooler? My original plan was to get the pro touring 10r80 manifold with the coolant temp switch and the mishimoto universal transcoolar with fan. But I want to do a deep ppe and drop the coolant temp so I'm going to do the 170 spd and see if I can drop it down more so the h/x can cool up quicker. But if it's still bad I'm going the other route.

I added the inline thermostat since I live in a colder area. Without it the cooler would over cool the trans fluid and it would never get up to operating temps.

I didn't add a fan. It gets plenty of airflow since it's directly in front of the main radiator. I thought about doing the universal cooler but went with the raptor once since it was a direct fit and bolted right on with no issues at all.

 

[UstonXpedition]

I added the inline thermostat since I live in a colder area. Without it the cooler would over cool the trans fluid and it would never get up to operating temps.

I didn't add a fan. It gets plenty of airflow since it's directly in front of the main radiator. I thought about doing the universal cooler but went with the raptor once since it was a direct fit and bolted right on with no issues at all.

Me Being in texas. Your setup sounds a much better and less hassle of wiring. This would be a good option. Thanks for the insight.