I've scanned the posts discussing the Ford 7.3 liter gas engine and am surprised that no one has mentioned torque.
Torque is what pulls a heavy load up a long grade and the engine rpm at which the engine produces maximum torque is very important.
475 ft. lbs. is not a lot of forque in trucks now. I bought a new Ford F250 HD with a 460 ci gas V8, E4OD, and 4.10 gears in 1994. It produced 405 ft. lbs. of torque at 2400 rpm. That meant it would pull my Airstream trailer at 2400 rpm up (slight) grades in 2nd or 3rd gear at an easy 2400 rpm. The GM 454 produced about the same torque but at much higher rpm. In ttuth, the Ford was a dog. It delivered 10 mpg empty or loaded and couldn't get out of it's own way. The new Dodge-Cummins 6 speed w/3.55 gears I bought in 2001 would pull steeper grades faster in 6th gear at 1600 rpm. It produced about 540 ft. lbs. at 1600 rpm.
The specs below tell us that the nee Ford trucks produce a little more torque than in 1994 but to pull any load at all it will be winding 4000 rpm in a lower gear, guzzling fuel.
The Ford 7.3 gas engine is a powerful and advanced gasoline engine for Super Duty trucks and other applications1234.
Some of the specs of the Ford 7.3 gas engine are12354:
- Displacement: 7.3L, 445ci
- Compression Ratio: 10.5:1
- Horsepower: 430 hp at 5,500 rpm
- Torque: 475 lb-ft at 4,000 rpm
- Bore: 107.2 mm
If it was my choice, I would prefer a clean, relatively low miles used diesel dually. My choice would be Dodge-Cummins but all three will get the job done. If you drive an empty or lightly loaded truck, gasoline is fine but a diesel is required to pull a trailer up a hill.