Well i own a 2000 dodge ram with a 8.0 liter v10 that makes 310 hp and 450 ft. lbs of tq, and also own a 2001 Cummins with roughly the same power (stock), the Cummins put the v10 to shame stock for stock. Once i added an intake, 4 inch straight pipe exhaust, and a power programmer the cummins made the v10 feel like a ford ranger.
For power and pulling heavy there really is no other choice then a diesel.
Also let me add my v10 pulls heavy loads with little to no effort, and i have never actually "needed" more power from it while towing, but the diesel does it better, does it faster, And struggles far less. it also gets more then double the mpg while doing it.
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