This is what GMC gives buyers with the new XL version of Motor Trend's 2002 Sport/ Utility of the Year winner. The '03 Envoy XL has a 13-in.-longer wheelbase than the standard Envoy, allowing a third-row seat to slip in. There are now two engine choices: the 4.2L/275-hp I-6 and a new, all-aluminum OHV 5.3L/290-hp V-8. Order the V-8 and torque ratchets up from the straight-six's 275 lb-ft to 325. This translates into more towing capability, 7200 lb in 2WD compared to 5900 lb for a 2WD I-6 model. Both engines use regular unleaded fuel, and V-8 mileage should only be about 1 mpg less than the 4.2's., , Available in 2WD and 4WD, the Envoy XL tips the scale at about 300 lb heavier than the Envoy, so the V-8 doesn't feel much quicker than the six. Put a load on the hitch, though, and the V-8's low-end grunt is appreciated--so is the Corvette-like exhaust note. GM's 4L60-E four-speed automatic is used behind both engines. Shifts under light or heavy throttle are the same: creamy. A 3.42:1 rear-axle ratio is standard, while a 3.73:1 gearset is optional with the V-8., , On the road, the long-wheelbased XL is comfortably communicative. Accessing the aft-row seat requires some amount of nimbleness, but the interior is still a functional place to live. With the V-8-power XL, GMC has expanded the Envoy's appeal to include those needing a third-row seat and/or larger towing ability. As we said: It's just more...