The 2001 & 2002 5.9L Cummins was 235hp/460tq (auto or 5 speed) or 245hp/505tq H.O. (6speed stick only) from the factory.
The diesel will pull at lower rpm with much less transmission shifting. It will also get 50% better mpg towing or empty.
However, if you were to add a set of six Rv275 injectors ($300 and ~40hp) and a $100 Edge EZ box good for another 50hp or so at the rear wheels, and that 02 Cummins would leave the 8.1L sucking its tailpipe.
That's how I had my 2002 2500 modded. It was absolutely amazing towing or empty. Sadly, the old quad cab (half sized back doors) was just too small for my growing family.
