I have 204,000 on mine delivering Airstream TTs from the manufacturer to their dealerships for a living. The most common destinations take me over the Rockies. I know very well what this truck will do in the heat and over the grades with a load. In fact I have been over Ike a few times with a TT. Yes 3.92 4x2 is optimum but their truck had the worst most restricting grill and the 33" tires not the 31.6" tires so it is not Ram's best possible towing set up. Like my truck but the fact that Ram put a CAC radiating heat in front of the radiator and blocking fresh air is stupid and hinders the cooling system. Edit You have been told that twice before in this thread and ignored it. Guess it did not fit your agenda.
http://www.ram1500diesel.com/forum/green-diesel-engineering/6740-coolant-temps-while-towing.html#post88686
I've never had a de-fuel on Ike but the truck would quickly with 7,200 pounds up that grade at WOT which is what they did. I have thought about it as you say and as stated towed up it more than once. He should have had the temps screen up then we would know for sure. The stupid dial gauge only tells you that the coolant was running warm but not so hot as to turn on the red idiot or warning light for coolant temp. More importantly in this case is that gauge does not tell you what the oil temp is.
What normally would happen and likely did was that his oil temp got to 266 which we would have seen on the other screen and a warning light would have came on there. My understanding is shortly after reaching an oil temp of 266 and the light coming on the computer starts limiting fuel to keep it cool and protect the engine. Prolonged WOT under extreme condition being culprit here and or the limited cooling system however you look at it.
Don't hold me accountable for what some other poster said about an ED out towing an EB up a hill. What exactly is it you are keeping real? I never exaggerated this trucks abilities. If so show me where. I am not the one hung up on horsepower either. The two primary reasons I got a tune was to program in a turbo brake and defeat EGR. And yes a little more HP & TQ and an overall fuel economy bump was nice. In fact earlier in this thread I stated about the relationship between horsepower and torque as I think its helpful for many to understand it better. I said;
On the relationship between horsepower and torque. I find this concise and useful in understanding or comparing so to speak. It may not be all inclusive but it helps get a handle on what many people struggle with.
"Torque is how much work an engine will do at a given rpm. Horsepower is how fast it will do that work at that rpm."
Both are important and have their value but you start to see the relationship more clearly. Gearing being the same, the engine with the most torque will tow the heaviest load up a grade.
So simplistically if gearing were equal both the 420TQ ED and the 420TQ EB should move the same load up a grade. But the EB having superior HP (at whatever its 420 TQ is reached at) will move the weight or load up the grade quicker or with better wheel speed assuming the same gearing or more accurately final drive ratio. end quote.
Naturally since gasoline only has about 85% of the power of diesel in it by volume it takes more of it to do the same work. And the fuel consumption difference was shown in your video. You may have a horsepower hangup I plainly do not. I never felt any need to make any excuse whether you think I should or not. I merely stated what I suspect we were seeing in the video you posted. I come to the forum to learn and to contribute. Looking back through this whole thread you obviously come for other purposes.