Towed the offroad rig yesterday. 90 to 95 degrees outside temperature, not more than 8k of weight, and a hand full of 6% grades between 3000 and 6000 ft elevation. Driving 60 to 65 mph up the grades the coolant temperature appeared above the gauge. Came on at 219 degrees, went as high as 225 and when the hill was crested quickly returned to 216 and the numerical display went away. Happened about a dozen times on the way to the destination and on the way home with 105 degree outside temperature. First time that has ever happened.

Coolant level is between min and max, was flushed at dealer about 20k miles ago. Fan sounded like it engaged and disengaged, it's pretty quiet. Is this normal operation?

 

Sounds perfectly normal to me.
225 is not overly hot for the operating conditions.

 

+1 on its normal.

 

Ok, thanks. I guess every other diesel truck I've owned over the past 20 years must have run at the same temps - just never had one that gave a numerical readout.

 

These newer trucks run hotter for sure.

 

We just came across California to Michigan on I80
15k 5th wheel. 95 - 108 outside temp when the sun come up. Up to 8000ft grades. Pretty much the same experiences as you on the coolant temperature gauge. I’ve seen it before so I didn’t bother me.
I love to hear the truck work going up those grades.
And you still pass everything insight. Now coming down the other side you definitely need to slow down and the engine brake definitely helps. 2020+ 6.7L are just amazing with the power and torque.
One thing I have learned is don’t let the truck slow down at the beginning of the up grade. With the cruise control set make it down shift with your foot before it starts to pull. Only takes a second and then remove your foot and then it will pull right up the grade with out dropping 3-5 mph.
A few more interesting numbers when working hard:
Oil temp 201/220
Trans temp 210/225
Turbo boost 20-30
2500 miles
65/80 mph posted limits outside of cities
65/75 Cruise control set.
16.5 mpg at start/ 11.3 mpg arriving Michigan per gauge in truck. Did get as low as 10.8 but gained a little bit when we got back on the flat land.
Tire psi 60/80 cold and 70-72 front / 90-94 rear Hot.
I was a little concerned about the tire pressure but some research showed that’s pretty much normal and within specifications. I did touch every tire including the camper at every stop and none where ever hot.

 

All normal for the newer trucks. I find that clutch fan engages earlier based upon oil temp and not so much coolant temp.

Oil temp can get to around 225F first and the coolant will still be just above 200-210.

I believe that since the increased hp/tq that it is a little more aggressive for 2021/22 models.

 

Both the coolant and transmission gauges will display the digital temps when a high temp is reached. I don't recall what they are, but I've seen it a bunch of times on my 2018 and expect the 2022 does the same.

You can also watch the temps come down pretty aggressively when the engine fan kicks into high speed. It's kind of nice to know and to see those things working as they should.

One day I'll get ambitious and run Forscan to put those digital temp displays on permanently.

 

i just towed my 26ft old heavy tow behind toy hauler from CA to AZ. Ended up going up Yarnell hill like I didn’t even have a trailer behind me. It was 110 all the way to the mountains. I was doing 70ish the whole way. My truck was at 235 engine & coolant. I have the low temp thermostat too from SPE. I’m considering getting the upgraded heat exchanger that helps lower temps as well. My dad owns a ‘12 and when he goes through the desert flat highway at 80mph 110+ temps, his truck was running 235 no trailer or anything. So these trucks run hot. Not sure what the derate temp is. But I know oil temperature can run up to 260 in general.

 

+1 for normal. Use Forscan and have them displayed all the time.

 

i spoke with S&B last week, I can’t get my miles to empty past 775. I adjusted my MPG on the truck to make it accurate for the big tires. So I get between 12-14mpg. And when I fill my truck up it stops at 775. S&B told me once my gauge goes to fill it take another 8 gallons because of the way the tank is designed