2022 GMC Sierra 3500HD

The Sierra 3500HD is available with a choice of a 6.6-liter gasoline V8 (401 horsepower, 464 lb-ft of torque) paired with a six-speed automatic transmission or a 6.6-liter turbocharged diesel V8 (445 hp, 910 lb-ft) with a 10-speed automatic transmission.

Pro, SLE and SLT trims come standard with rear-wheel drive and optional four-wheel drive. The AT4 and Denali offer four-wheel drive exclusively. A dual rear-wheel option is available on certain cab and bed configurations of the Sierra to boost the truck's towing capacity.

Pro
The base trim is relatively bare-bones and comes with:

• 18-inch steel wheels
• LED headlights and taillights
• Manually adjustable trailering mirrors
• Cargo bed steps
• Locking tailgate and spare tire carrier
• 40/20/40-split front bench seat
• Vinyl seats and floor coverings
• Manual windows and door locks (regular cab)
• Trailering hitch
• 7-inch touchscreen infotainment display
• Apple CarPlay and Android Auto smartphone integration
• Dual USB jacks
• Six-speaker audio system

SLE
Adds more convenience features, such as:

• 18-inch alloy wheels
• Upgraded exterior trim
• Power trailering mirrors
• Configurable (MultiPro) tailgate
• Integrated brake trailer controller (allows adjustment of a trailer's brakes from the cab)
• Cloth seats and carpeted floors
• Front underseat storage
• Cruise control
• Power door locks and windows
• Remote keyless entry
• 4.2-inch color driver information display
• Satellite radio
• Connected services including a Wi-Fi hotspot

SLT
The SLT starts moving into premium territory by adding: 

• Power-folding and extending trailering mirrors
• Cargo bed lighting
• 120-volt power outlet in cargo bed
• Keyless access with push-button engine start
• Remote engine start
• Dual-zone automatic climate control
• Leather seats
• Power-adjustable driver's seat with memory settings
• Heated front seats
• Heated steering wheel
• Second-row USB ports
• 8-inch touchscreen infotainment system display
• Wireless functionality for Apple CarPlay and Android Auto
• High-definition backup camera with hitch-view angle

AT4
Comes with most SLT features but adds off-road attitude and capability with:

• Standard four-wheel drive
• Hill descent control
• Off-road suspension tuning
• Underbody skid plates
• Body-color bumpers
• Spray-in bedliner
• Front bucket seats with center console
• Ventilated front seats
• Heated rear outboard seats

Denali
Tops the Sierra 3500HD lineup with features including:

• 20-inch alloy wheels
• Automatic high-beam headlights
• Chrome exterior trim
• Power-sliding rear window
• Side steps to ease cab entry and exit
• Premium leather seats
• Upgraded driver information display
• Navigation system
• Bose premium sound system
• Wireless smartphone charging
• Bed-view camera

The Denali also includes a number of safety features and driver aids, many of which are optional on other trims.

• Forward collision mitigation (warns you of an impending collision and applies the brakes in certain scenarios)
• Lane departure warning (alerts you if the vehicle begins to drift out of its lane)
• Blind-spot warning with rear cross-traffic warning (alerts you if a vehicle is in your blind spot during a lane change or while reversing)
• Surround-view camera system (gives you a top-down view of the Sierra 3500HD and its surroundings for tight parking situations)
• Parking sensors (alert you to obstacles that may not be visible in front of or behind the vehicle when parking)
• Safety alert seat (warns of potential side collisions with vibrating pulses on either or both sides of seat to indicate direction of danger)

There are more than 30 option packages and around two dozen stand-alone options available for the various trims. Mostly they add features to the lower trims that are standard on the higher trims.