The standard front seat setup in a Yukon XL is a three-passenger reclining 40/20/40 split bench with six-way power driver and passenger seat adjusters with dual manual lumbar support. Front bucket seats are available and we like them better when seven or fewer passengers need to be moved. Either way, the front seats in these vehicles are generally comfortable and supportive. Seat belts mount to the seat frame, and the side-impact airbags are incorporated into the seats. The basic GMC Yukon XL comes with nice custom cloth upholstery. Leather seating is available as part of an options package. Leather seating surfaces come standard on the Denali, and its tone-on-tone leather bucket seats suggest a luxury sedan more than a truck; 10-way power adjustments include side bolsters, lumbar support, and articulated headrests.

For the second row, the standard deal is a three-passenger 60/40 fold-down bench seat. Denali offers a choice of 50/50 split bench seat in the second row or a pair of heated bucket seats for $490. Because it seats three people, the bench seat offers more options for carrying passengers. If four adults plus two children is all you'll ever need to carry, then the second-row bucket seats are very comfortable. Second-row passengers in the Denali's optional bucket seats get a great pair of cup holders that flip out of the back of the center console. Just above are their comprehensive audio controls and headphone jacks. A pair of covered cigar-lighter style power outlets is available for running accessories. Besides the seat heaters, they get a pair of ceiling vents on each side that can be aimed. The driver controls the rear passengers' temperature and fan speeds and can direct the air to upper or lower vents or both.

The third row is a bench seat. It is surprisingly comfortable, unlike most third-row SUV seats. While many third-row seats put a fender under half your butt, leaning your body toward the inside, the Yukon XL provides a comfortable bench seat. Larger passengers may not love sitting back there, but most adults can tolerate the third row. There are cup holders for each person, great when heading to an event with a boatload of friends. Overhead vents can be aimed for heating and air conditioning, good because the rear side windows cannot be opened. A pair of three-point seat belts are nicely designed and easy to use. As with the other rows, the seat belts are integrated into the seats, which is the direction many manufacturers are taking now. There is a lap belt in the center of the third row, but putting three people back there is optimistic as the third row is considerably narrower than the first two rows to accommodate the rear wheels. Getting into the third row is a bit challenging, however. Third-row passengers will require assistance to get in or out as someone will have to move the second-row seats out of the way for them. Minivans tend to be much easier to deal with in this regard.

Need to haul some stuff? Yukon XL offers 45.7 cubic feet of cargo space behind the third row. That's a lot. By comparison, a regular Yukon or Tahoe provides just 16.3 cubic feet and a Ford Expedition offers 20.5 cubic feet. Fold third-row seatback down, then tumble the seat forward and you'll have a lot more storage capacity. We don't have figures, but it opens up a lot of space with minimal effort and you'll still be able to carry four to six people, depending on the seating package you have. A pair of tethers is supposed to secure the third row in the up position, but they are flimsy (one of ours broke); it seems like they could have come up with a better solution. So be careful about putting a dog back without propping that seat up as there is a chance the seat could fall back down.

Need to haul a major load? Pull that third row out and stick it in the garage. That strategy provides 90 cubic feet of cargo room. Next, flip up the second-row seat bottoms, fold the seatback down, then flip the folding carpeted platform backward to cover the third-row platform. You're looking at a flat floor with 131.6 cubic feet of space, great for runs to the home-improvement center or big outdoor outings. This is one of the few vehicles that offers comfortable sleeping accommodations, a real benefit when fatigue takes over during the long trip home after fishing the evening rise.

Back up front, the Yukon XL and Denali driver is provided with excellent ergonomics. Switchgear is functional and seems familiar yet contemporary. Audio and climate controls are easy to operate without undue distraction. All Yukon XL models come with a high level of standard equipment. Our Denali came with an easy-to-operate six-disc CD changer mounted below the trip computer; this seems to be the best solution as it's within reach of the driver and does not take over the glovebox. Cup holders are superb, an important feature for people who live and work in these things. A pair of map lights is mounted above and can be aimed, one of the best designs we've seen. A covered power outlet is conveniently located for cell phones and radar detectors, and this is in addition to the cigar lighter inside the ashtray compartment. Rear heating/air conditioning controls, if available, are mounted overhead. Front and rear heating and air conditioning is standard on all Yukon XL models; automatic climate control is optional on Yukon XL models, and standard on the Denali.

There are also nicely integrated buttons for Homelink, which can open garage doors and gates and turn on house lights, and OnStar, the most widely accepted telematics system. GM's OnStar security and information service is standard on Denali, optional on SLT, and we recommend it. OnStar works well as a navigation system because there's nothing to program. Press the button and a human OnStar operator comes on asks what they can do to help you. OnStar operators will do anything short of organizing your daughter's wedding. OnStar always knows the location of your vehicle; they will notify authorities of your location if your airbag goes off and you do not respond to their calls. Press the emergency button and they'll send out the troops. They can also unlock your doors if you lock the keys inside. OnStar is a great safety feature.

A deep but short center console in the Denali provides slots at the bottom for CDs. The top of the console pops open to reveal a separate shallow compartment with a rubber mat and a net in the lid, good for sunglasses and other small items, though a little awkward to reach.

Other Denali features include teal-green instrument lighting, cloth-covered sun visors with pull-out extensions and lighted vanity mirrors, theatre dimming of interior lamps, and nine acoustic floor dampers to keep things exceptionally quiet.

Buyers of basic SLE or SLT Yukons can select either side-by-side cargo doors or an all-aluminum liftgate with a glass section that lifts independently. the liftgate is convenient for quickly adding and removing lightweight items to the cargo compartment. We like the cargo doors because they open wide and allow a closer working position to the vehicle's storage area. Cargo doors are useful when pulling trailers because they will usually clear the trailer tongue jack. The hinges can be released, allowing the doors to open fully when loading large items. However, the luxury-oriented Denali offers only the lightweight liftgate. The liftgate has the advantage of offering better rearward visibility than the cargo doors, which block the view in the center where the doors meet. Most people find the liftgate preferable.