My truck when pulling 41K today in 90 temps ranged from 210 to 229 with the fan running most of the time. Truck runs just as hot deleted as it did stock.
I had a 04 and a 06 5.9 cummins with a smarty/ TST pulling the same trailer and it took 100 temps before I ever head the fan come on. Is the radiator smaller with the 6.7 cummins.?

 

OK I have 2012 3500 4:10 gears, 21k lb fifth wheel, just got back from 3500 mile vacation to yellowstone from san Diego CA. Needless to say a FEW steep grades between. Was 116 degrees near Vegas, Outside Air temp, 7% grade, nearly topped my temp gauge, 237 degree on digital gauge, 208 tran temp. was the hotest on whole trip.

 

I was pulling grade in top gear, 6th, auto, keeping speed at 60 mph. I think it is bad engineering to have a Engine that can pull grades so easily but have to downshift to keep from overheating!

 

Even at these temps, no engine lights!

 

Hold it to the rug and don't look back, emissions truck all run hot, ever see one melt?

 

I HAVE seen them boil over!

 

If you notice on the current ram web site, one big "improvement" they're toting is dual radiators. Not sure if the size changed but according to my dealer and STAR, they run them hotter than the 5.9. To me it screams "we have a problem with cooling and we just admitted it with this statement".
http://www.ramtrucks.com/en/groundbreakers/#engine

I was told to mat it and don't look back don't look down. Kind of reminds of a Jason Aldean song. lol

 

Running hotter was intentional, it provides better mileage and fewer regens.

But rejecting the amount of heat that 385hp makes, considering the higher EGT's for emissions and it is going to take some cooling improvements.

 

I was thinking of the duel RAD design, was wondering if one might just be for the EGR cooling? If so a good idea, IMO

 

Well, dropped the truck off at the dealer yesterday for the coolant leak again. It is leaking worse than it did before. I assume the same problem. I didn't even bother to look. Not very happy. Dealer is up over the mountain from me about 40 miles. Interstate was shut down due to snow and wind. Crappy day to have to do it but I do live in Montana. lol Anyway, should be getting a call today some time to let me know what the deal is. They sure do have quite a few 14's on the lot

EDIT:
Just got the truck back. Radiator cap wasn't holding any pressure. I guess I will try it again and see if it leaks anymore. He figured that's why this Summer I was having high temps while pulling. I don't know what to think anymore. lol