The VW Touareg spans a broad range of fuel economy ratings with its three powertrains. If you're looking for the ultimate driving range, the diesel version is best, but a hybrid model also improves on the basic V-6's numbers.
The roomy Touareg's standard V-6 engine earns the lowest numbers of the lineup. The EPA rates it at 16/23 mpg, understandable for its size but off the mark when less expensive five-seaters like the Cadillac SRX are compared. Both the hybrid and TDI turbodiesel models top that easily; they're rated at 19/28 mpg (TDI) and 20/24 mpg, though with either, there's a stiff price premium.
In truth, Volkswagen's effort with the Hybrid doesn't make a very good argument for itself, as the Hybrid is not only much more expensive than the TDI but worse in combined fuel economy. While we value the Hybrid as a stepping stone toward greater electrification, we'd advise shoppers to make the practical choice toward the TDI—especially if they plan to do more suburban or highway driving.