From the least expensive version, plan on adding $2,000-$3,000 to step up from regular cab to Extended cab, or from there to Crew Cab.   Figure $200 more for a long bed version.   Add about $3,000 for four-wheel drive.  

Sierra WT models are work trucks with gray vinyl upholstery, rubberized floor covering, black door handles and mirrors, steel wheels and floor-shift for 4WD.   They come with air conditioning, AM/FM stereo, driver information center, 40/20/40 manual-recline front seats, rear bench seat, tilt wheel, chrome grille and bumpers, tow hooks, intermittent wipers, and dual dash power outlets.   The WT Crew Cab has a 60/40-split rear bench seat.   Options on WT include cruise control ($250), stereo upgrades, OnStar 9.0 ($295), 18-inch wheels, camper mirrors, locking differential ($325), trailering equipment, power windows, mirrors and locks, integrated trailer brake controller ($200), deep-tint glass and bucket seats.  

Sierra SLE versions improve with cloth upholstery, carpeting (though the WT floor is available), 40/20/40 front seat with locking console storage, split-fold rear seat, AM/FM/XM/CD/MP3 RDS stereo, OnStar with six months' service, cruise control, aluminum wheels, power heated mirrors/windows/door locks, visor vanity mirror/lights, side moldings and electric-shift for 4WD.   SLE options include dual-zone climate control, navigation and backup camera, backup camera in mirror ($450), power passenger seat for the 3500 Crew Cab, steering wheel controls, power sliding rear window ($250), power heated camper mirrors ($243), 20-inch wheels for the 2500, locking differential, Z71 off-road package with shocks, bump stops, 36-mm front antiroll bar, and skid plates.  

Sierra SLT upgrades with leather, 10-way power heated front seats and two-person driver memory, dual-zone climate control, Bose DVD audio system, Bluetooth, console, auto-dimming mirrors (3), steering wheel controls, fog lamps, paint-matched trim, power folding mirrors w/signals, 18-inch polished forged aluminum wheels, locking differential, trailer equipment and integrated trailer brake controller.   SLT-level upgrades include navigation and rearview camera, rear-seat entertainment, moonroof ($995), power sliding rear window, power heated camper mirrors, and 20-inch wheels on 2500.  

Denali models come in 2500 or 3500, single or dual rear-wheel configurations, 2WD or 4WD, short bed or long bed.   Denali is Crew Cab only.   Denali gets a unique four-bar grille, body-color bumpers, chrome door handles, chrome accents, polished forged aluminum wheels, and EZ-Lift locking tailgate.   Inside, Denali adds unique brushed aluminum trim, power-adjustable pedals, a Bose premium surround audio system with 6CD/USB, Bluetooth, and 12-way power seats.   Options include a heated steering wheel, heated and cooled front seats, moonroof, and rear-seat entertainment.   Denali comes only in black, gray, or white.  

Optional on most trim levels are roof marker lamps ($55), skid plates ($150), snow-plow prep for 4WD, fast-idle switch ($200), camper/fifth-wheel wiring ($35), myriad dealer options and for diesels, dual 125-amp alternators ($270) and radiator covers ($55) for cold states.  

Safety equipment includes frontal airbags, front seat belt pretensioners, and StabiliTrak on single-rear wheel models.   Optional equipment includes front-side airbags and front side-curtain airbags (2500), OnStar, backup cameras and integrated trailer brake controller.