The Michelin Energy Saver A/S tires are indeed more efficient than the Continental Procontact TX (less rolling resistance). That, along with the smaller diameter wheel on the LX/EX makes for a significant difference. It would be interesting to see if someone put Michelin Energy Saver A/S tires on the Touring's stock 17" wheels. Michelin offers then in Size: 215/50R17. That would be an apples-to-apples comparison of Touring versus the better trim levelsThe larger tires on the Touring seem to be the main reason for lower mpg versus LX/EX. And possibly material / construction differences between the Continental ProContact TX (Touring) and the Michelin Energy Saver A/S (LX/EX).