Originally Posted by TK-421
i ride in my friend's cummins 6 speed dually quite often and he only has a tune and we got over 30mpg driving to orlando from tampa and you can most definitely hear spool whenever he gasses it.
EDIT: he just told me he scrapped his cats so that's probably why you hear spool, my bad. this leads me to believe that he was just talking shit so disregard what i said about 30mpg too. i know for a fact that they can get in the mid 20's, though, without modification and you don't drive like a dickhead
Highly unlikley to achieve 30mpg in a Cummins. I own one. 17- 20mpg around town. 22 - 25mpg at best on the highway. 12mpg towing 17,000lbs. Combine the high cost of diesel fuel which negates the mpg savings, a rock hard suspension, and an iron block that literally takes 15 minutes to get warm, and you have a really uncomfortable DD. The only reason to buy a diesel is if you are towing, or using it as a work truck.