Acceleration

4WD ext. cab Z60, 5.3 V8	4WD cew cab Z71, 5.3 V8	4WD crew cab Z85, 5.3 V8	Denali	Class Average
6	6	6	7	6.2

Acceleration is more than adequate with the 5.3-liter V8 and robust with the Denali's 6.2 V8. Smooth-shifting transmission kicks down quickly for more passing power. Tow/Haul mode adjusts shift points for best performance with heavy loads. Denali's shifter-stalk-mounted manual-shift control works with an easy flick of the thumb.

Fuel Economy

4WD ext. cab Z60, 5.3 V8	4WD cew cab Z71, 5.3 V8	4WD crew cab Z85, 5.3 V8	Denali	Class Average
3	3	3	3	3.2

In Consumer Guide testing, 4WD Sierras averaged 14.1 mpg. Test Denalis averaged 14.6-15.9 mpg. All Sierras except the Denali use regular-grade gas. GMC recommends premium for the Denali. Some 5.3-liter engines can also run on E85 ethanol gas.

Ride Quality

4WD ext. cab Z60, 5.3 V8	4WD cew cab Z71, 5.3 V8	4WD crew cab Z85, 5.3 V8	Denali	Class Average
5	5	6	5	5.2

Sierra's Z85 suspension provides a comfortable, compliant ride, and there's less reverberation over bumps than in most pickups. Stiffer Z60 suspension makes the ride more jittery over smaller bumps, partly due to its 20-inch tires vs. standard 17s. Available Z71 suspension is suited to off-road duty. It exhibits some choppiness over pavement cracks and washboard surfaces, though it's not overly harsh in everyday driving. Denali with 20-inch tires composed enough, though the standard 18s are likely to offer more stability.

Steering/Handling/Braking

4WD ext. cab Z60, 5.3 V8	4WD cew cab Z71, 5.3 V8	4WD crew cab Z85, 5.3 V8	Denali	Class Average
4	3	3	3	3.5

Being these are large pickups, there's noticeable body lean in fast turns and quick changes of direction with Z85 suspension. Z60 and Z71 suspensions improve handling only slightly. The steering is nicely weighted, if a bit numb, and the brakes are responsive with fine pedal feel.

Quietness

4WD ext. cab Z60, 5.3 V8	4WD cew cab Z71, 5.3 V8	4WD crew cab Z85, 5.3 V8	Denali	Class Average
6	6	6	6	6

Road noise in Sierra is lower than in most pickups. The 5.3-liter V8 is a model of refinement. Wind noise intrudes only above 60 mph.

Controls

4WD ext. cab Z60, 5.3 V8	4WD cew cab Z71, 5.3 V8	4WD crew cab Z85, 5.3 V8	Denali	Class Average
7	6	6	7	6.1

The gauges are easy to see and read. Sierra's Pure Pickup interior places radio and climate controls high on the dashboard, just out of easy reach. The available luxury interior mimics that of the Yukon large SUV, with controls mounted lower but within easy reach. The optional navigation system absorbs some audio controls but doesn't complicate their use. Denalis expand on the luxury interior, with upgraded trim and overall upscale feel.

Details

4WD ext. cab Z60, 5.3 V8	4WD cew cab Z71, 5.3 V8	4WD crew cab Z85, 5.3 V8	Denali	Class Average
6	5	5	6	5.6

Pure Pickup interior materials are better than expected of a work-oriented truck, but are not extraordinary by absolute standards. The Luxury trim ups the ante with materials that are a cut above the pickup norm, even though most surfaces are hard plastic.

Room/Comfort/Driver Seating (front)

4WD ext. cab Z60, 5.3 V8	4WD cew cab Z71, 5.3 V8	4WD crew cab Z85, 5.3 V8	Denali	Class Average
9	9	9	9	9

Ample room for adults. Both the bucket and bench seats lack side support in fast turns but are firm and comfortable. Visibility is generally good, though the extended cab's thick rear pillars hinder view to back corners. Short drivers will appreciate the optional power-adjustable pedals.

Room/Comfort (rear)

4WD ext. cab Z60, 5.3 V8	4WD cew cab Z71, 5.3 V8	4WD crew cab Z85, 5.3 V8	Denali	Class Average
4	8	8	8	6.2

Generous headroom. Legroom is ample in the crew cab. Extended cab models have a seatback set at a comfortable angle, but legroom is in short supply. With the front bucket seats, the center console restricts foot space for a center rear-seat passenger. Extended's rear doors are available with power windows, which is a nice convenience. The doors open wide--nearly flush with the cargo bed--for easier entry and exit, but if fully open, a seated passenger can't close them.

Cargo Room

4WD ext. cab Z60, 5.3 V8	4WD cew cab Z71, 5.3 V8	4WD crew cab Z85, 5.3 V8	Denali	Class Average
5	6	6	6	4.6

On both extended and crew cabs, the rear seat cushion flips back against the seatback, leaving a large cargo area with a nearly flat floor. Pure Pickup interior features upper and lower gloveboxes; Luxury interior has only a lower one. In front, the bucket seats come with a roomy console bin, while the bench seat is available with a flip-down center armrest that doubles as a large storage bin. Otherwise, there are few other interior storage cubbies.

Value within Class

4WD ext. cab Z60, 5.3 V8	4WD cew cab Z71, 5.3 V8	4WD crew cab Z85, 5.3 V8	Denali	Class Average
7	7	8	8	7.6

GMC's Sierra and the similar Chevrolet Silverado are among the best large pickup trucks for refinement and available features. Any truck buyer would be well-advised to give these 2008 Recommended picks a long, hard look.

Total Score

4WD ext. cab Z60, 5.3 V8	4WD cew cab Z71, 5.3 V8	4WD crew cab Z85, 5.3 V8	Denali	Class Average
62	64	66	68	63.2

Scores for all Large Pickup Trucks

Low Score		57
Average Score		63
High Score		68