Re: 7.3 or 6.0 used
I vote 7.3L, much more reliable. A couple fleet vans I had with the 6.0L diesel did get slightly better mileage, but an injector went every few months, which not only set me back cash, but a couple days of having to get another vehicle while that one was in the shop.
I'll also mention that the aftermarket has LOTS more parts available for the 7.3L diesels, if you decide to do some upgrades down the road....
'11 Ram Quad Cab 4x4 SXT 5.7L HEMI (stock); 48,500m
'06 Pontiac G6 GT 3.5L 220hp; 64,000m
'12 Chrysler 200 Limited 3.6L 283hp; 28,000m
'99 Taurus 3.0L 2V Vulcan 145hp; 154,300m - Traded
Amsoil in all vehicles!