Another advantage of duals is if you have a flat on one of the rear 8 tires and not a lot of cargo weight, you can still drive.From personal experience and testing results at the Yuma Proving Grounds, there are few reasons to stick with duals:
1...you carry lots of weight on highway. OK.
2...It's original equipment. Perview of purists.
3...They make you feel good via the looks of them. No comment.
Other than that, big singles do more for any truck off-road or in crappy situations.
And you never have to pull two wheels to change an inside flat...