I even said it matters what the truck is for in my 1st post here.

At only 18 MPG the cost offset of the MPG still favors the gas engine.....especially when the cost of buying a diesel and modding it comes into play vs. gas.

Plain ole GM bulk diesel oil change is $50 vs. $20 for a gas engine. Fuel filter is $50 that needs replaced every 12-15K miles vs $25 for a gas that needs changed every 30-40K miles.

A dmax auto truck is $12K more than a 6.0 with all other options being the same.