Gas mileage isn't the strong suit of the 2012 Nissan Quest. It sits at both the top and the bottom of the class, which makes it especially important for you to know how much you typically drive on the highway or in town.
If you're simply looking at highway mileage estimates, the 2012 Quest falls behind nearly all of its family-toting. The EPA numbers are 19/24 mpg. The latest Honda Odyssey posts highway numbers as high as 28 mpg; every Chrysler minivan is pegged at 25 mpg. The Quest's highway number is as low as that of the much larger Sienna, though the Toyota's mileage drops to 17/23 mpg when it's shod with all-wheel drive.
However, for city mileage, the Quest is a leader. Its 19 mpg equal the Sienna and the Odyssey, while Chrysler's minivans check in significantly lower.
No hybrid or diesel editions of the Quest are planned.