Weeell Not exactly there Tandem...
First of all this is physics and that doesnt change. No matter how much you want it to.
Second the auto mfgs know this well...but there is big money in convincing you you need all that torque and HP...their biggest profit margin vehicles are the Expensive pick ups. Most of it is marketing BS. This is more about whose got the Biggest One, or playing to the male ego.
And yes Class 8 trucks do run some 500+ Hp vehicles. But you dont need that to haul 80K LBS. In Europe and other places loads exceed 100,000 lbs and they have been doing it with much less HP In the 380-420 range for many years ...even up and over the Alps.
Whats more important on hills than raw HP is the RPM Range that you can deliver that HP in. IE how far down the rpm scale can you lug the engine before changing gears. Also if you look carefully most Class 8 over the road trucks (except construction) use axle ratios in the 3:00's, 3:42 etc.
Sorry but from an engineering perspective and Physics the OP is correct. (at least in the main. I may have worded some things a bit differently but as I read it is a pretty good explanation)
In my opinion we have all been sold a bill of goods by the auto industry that has more to do with their profits than it does with any real world NEED for all of this ever bigger and bigger numbers game for HP and Torque.
It is fun to discuss all this HP vs torque stuff. I doubt this has changed anybody's mind. I doubt anybody wants to change the physics. Maybe some want to understand it better. At the end of the day what is important is the seat of the pants drivability. As you indicate, numbers on a towing website might be more for sales than anything else. How many consumers of pickup trucks really can tell the difference between torque values when there are so many other variables (tire sizes, transmissions, rear end ratios, HP, RPMs where the engine makes most HP and/or torque, etc.). Consumers just want something that works. This thread is textbook stuff. Ford, GM and Ram simplify it as who has the most torque.
With motorcycles the manufacturer's compete with HP, same thing with most high performance cars. The Viper has 500 HP, the Mustang 600, etc. If you want to find the torque values you often have to dig for them. Lycoming and Continental light plane engines are rated by HP.
So, maybe you are right that pickups are sold by torque values because that is what consumers of trucks
think they want to see because they are told that is what they want to see by the manufacturers as a comparative value regardless if it tells the whole story; and it probably doesn't. I am not sure consumers even care about the whole story. They just care about how the truck performs. The higher the torque value
presumably the better the truck will perform towing. Does it really? How would they ever know as the diesels already flatten the hills and have all the power anybody would want. Whether torque or HP really does that or not can be debated all day in forums like these where textbook stuff clashes with marketing. When the reality is that both HP and torque are important and both needed to move the truck.
It is very hard for most consumers to look at a 6.4 410 HP gas engine with 429 foot pounds torque and then look at an engine with about the same HP and 865 foot pounds torque in a sales or towing guide and think HP is the predominate determnator of towing power when the higher torque engine can tow almost twice the weight. Same HP, twice the torque equals twice the towing weight. If that is all about marketing then Ram, Ford and GM do a great job convincing us torque is the most important factor in towing performance. Torque screams performance in the sales literature.
However, this brings me back to my original comment to the OP. If HP is so much more of an indicator of power and performance than torque (all other things equal which they never are), I will be a believer when GM, Ford and Ram change the emphasis from torque to HP in their tow guides. It is a torque war today; it could just as easily be a HP war. For some reason they keep it a torque war.
