Higher horse power is not a factor for fuel economy

What are you expecting to do with it and where are you traveling? Route?

 

Is it more expensive on fuel if your truck have a highest horse power?

 

Horsepower is not what is pulling the load, torque is. Compare torque and go from there.

 

The driver is the main variable. If you know how to drive, a high hp truck will get better mileage. If you smash the pedal to the floor on ever gear you'd be better off with a low hp truck.
Just because the horses are in the barn does not mean you have to feed them.

 

and there you have it.

 

Horses don't need water unless you use them .
I would rather have big horses and not use them than to work my pony to death to do the same job .

 

Thats not entirely true. @ engiones with same tourqe, 1 with 100 more HP, the higher horse engine will get up the hill faster everything else the same.

In general, high horse engines dont use more fuel. BUT!!!! if the driver uses all that extra horse all the time it will kill mpg. A good driver can get better mpg with a higher horse engine, but a poor driver will always use the extra power and get horrible mpg.

 

The 430 HP Detroit, and the "C" Cat were good fuel milage engines, there is a tag that tells you what fuel is used to make the HP it is the EPA tag in MM3 of fuel.
If one engine takes 300 MM3 to make HP and the other 400 guess wich one is fuel eficient.
The driver is very important, I see it every day drivers going from full power to full Jake's makes no sence, driving full speed over the crest of a hill, drivers do not coast. A large engine, is not as fuel efficient in the flats, west of the rockies, to small an engine is not eficient if it is at maximum power all the time. Every condition and area has different requirments, but having 600HP and 2050 torque so you can crest a hill faster, that takes 10 minutes to pull is not eficient.
Slow and steady wins.
Just a thought!

 

Rather try to explain things, here a couple articles for your reading pleasure;

http://auto.howstuffworks.com/difference-between-torque-and-horsepower1.htm


http://trucks.about.com/od/autobuying/a/torque.htm


http://www.bankspower.com/techarticles/show/27-why-diesels-make-so-much-torque