DD15 455HP vs DD15 560HP

on a hill, the high powered motor will complete the hill fast and will use more fuel. that's why big companies don't use high powered motors.

 

Sorry. I can't agree. My big motors are getting way better fuel mileage than the small ones. Even with drivers on them.

 

Well last week I did a rounder with dd16 600hp 2050 torque combined loaded and empty. 49 litres per 100km. This week I did the same rounder with a dd15 565hp 1850 torque. 47 litres per 100 km. the dd16 is much nicer to drive w/less shifting. The rounder was 657km half loaded half empty. The load is super B fuel tanks 63,500 is max we run um around 63,000.

If buying a truck I would go for the bigger motor!

Just though I would add this is Northern BC lots of mountains lol

 

mhyn, your contention is true, but your analysis is flawed. While the gallon per hour usage rate of a more powerful engine is indeed more than the lesser powered engine, it also is take substantially less time to get over the hill. The actual fuel used in the total hill climb more often is less with the higher powered motor simply because it was at max fuel consumption for substantially less time.

example: the lesser powered motor might use about 24 gal per hour / .4 gal per min under full load. and it takes, say, 30 seconds to climb a particular grade. For a total fuel consumption of .2 gallons of fuel to get over that hill.

Now we take a higher powered motor. It has a higher fuel consumption rate of, say, 26.5 gal / hr or .44 gal / min. But in this case, it only takes 20 seconds instead of 30 to get over the hill, using .13 gallons of fuel to do it, so there was a net savings in fuel of .07 gallons. Do that day after day after day, and the higher powered motor actually comes out ahead.

Of course, this is all dependent on a driver knowing how to actually drive and not just be a steering wheel holder. And keep in mind, fleet choices are motivated by many factors including insurance companies and motivations of truck OEM's to move various configurations of their pet products.

 

No, they don't use big hp motors because the drivers would tear the hell out of the driveline.

 

they don't care of drivelines ))) all trucks are new and under warranty. however day care of fuel saving and it a priority

 

Small motor equals.......cheap to buy due to lighter driveline, cheap extended warranties due to lighter driveline, and less chance of the "new breed" professional tearing it up as Oscar said.

 

560 horsepower 1850 torque engine would have FR16210B or FR18210B.. not FR15210B

almost all dd15 engines have label showing 560hp. the truth is they are not setup for 560hp. the glowbox label shows actual hp and torque.

 

I can tell you that the top truck weighs more with that heavier Meritor rear end on it. If wieght is a factor, yu'll lose 1000-1500 lbs on the top truck from the heavier rear end.