GM's just revealed a whole messload of details on their newest members of the GMT-900-based full-size SUV and truck lineup — the 2009 Chevy Silverado XFE, 2009 Chevy Tahoe XFE, 2009 GMC Sierra XFE and lastly, the 2009 GMC Yukon XFE. What's XFE? It stands for Xtra Fuel Economy and the four relative fuel-sippers join the already class-leading Chevy Cobalt XFE as vehicles GMs achieved added wallet-padding using a combination of mechanical, aerodynamic and mass-reducing enhancements. The tweaks help to deliver a 5% increase in EPA-estimated highway fuel economy and more than 7% improved mileage in city driving. They achieve 15 city and 21 highway mileage ratings versus comparable non-XFE models' 14/20 ratings. The XFE designation is only available on 2WD vehicles equipped with the 5.3-liter V8 mated to a six-speed transmission. But we're told they're able to accomplish the fuel economy bump without a knock to towing ratings. The Tahoe and Yukon are unchanged, while the Silverado and Sierra increase from 6,600 pounds to 7,000 pounds due to the new, six-speed transmission and high-capacity cooling package. Still with us? Good. Hit the jump for our take.

 

2009 Chevy Tahoe XFE [photos]