The cummins V8 only weighs like 150lbs more than the current Gasser in the Titan so I don't see that being a problem
The MPG thing people are misunderstanding completely, especially in this business. All the numbers people are quoting are unloaded. Whens the last time you serviced a property with nothing in the truck not hauling a trailer?
Unloaded the Dodge Diesel gets ~30mpg with 4x2 the Gasser gets 21mpg pretty much 50% more.
but the important thing is the loaded/towing numbers like everyone here cares about(or should).
In the F250 gassers we get 9ish towing the open trailers with 5 man crews. The diesels get 15-16 that 70+% better economy those numbers you can't argue with.
Friend with a dodge 3500 diesel gets 12-13 towing a 5thwheel RV my gasser 1500 gets that towing a 6x12.