2021 GMC Sierra 2500HD AT4 AT4 Preferred Package,AT4 Premium Plus Package,Driver Alert Package I,Driver Alert Package II,Gooseneck/5th Wheel Package,Gooseneck/5th Wheel Prep Package,Preferred Equipment Group 4SB,Technology Package,X31 Off-Road Package,6 Speakers,6-Speaker Audio System Feature,AM/FM radio: SiriusXM with 360L,Bose Premium 7 Speaker Sound System,HD Radio,Premium audio system: Premium GMC Infotainment System,Radio: AM/FM w/Premium GMC Infotainment System,Radio: Premium GMC Infotainment Sys w/Navigation,SiriusXM w/360L,Steering Wheel Audio Controls,Air Conditioning,Automatic temperature control,Electric Rear-Window Defogger,Front dual zone A/C,Rear window defroster,12-Volt Rear Auxiliary Power Outlet,120-Volt Bed Mounted Power Outlet,120-Volt Instrument Panel Power Outlet,Driver Memory,Memory seat,Power driver seat,Power steering,Power windows,Power Windows w/Driver Express Up/Down,Remote keyless entry,Remote Vehicle Starter System,Steering wheel mounted audio controls,Universal Home Remote,Manual Tilt-Wheel/Telescoping Steering Column,Off-Road Suspension,Speed-sensing steering,Traction control,4-Wheel Disc Brakes,ABS brakes,Dual front impact airbags,Dual front side impact airbags,Electrical Lock Control Steering Column,Front anti-roll bar,Front wheel independent suspension,Keyless Open & Start,Low tire pressure warning,Occupant sensing airbag,Overhead airbag,Power Door Locks,Power Sunroof,Pickup Box,Brake assist,Electronic Stability Control,Lane Departure Warning System,Hill Descent Control,Delay-off headlights,Front fog lights,Fully automatic headlights,Panic alarm,Security system,Unauthorized Entry Theft-Deterrent System,Speed control,2-Speed Active Transfer Case,220 Amps Alternator,Engine Block Heater,Exhaust Brake,Heavy-Duty 80 Amp Battery,AT4 High Clearance Step (LPO),Auto-dimming door mirrors,Bumpers: body-color,Front License Plate Kit,Heated door mirrors,IntelliBeam Automatic High Beam On/Off,LED Cargo Area Lighting,LED Smoked Amber Roof Marker Lamps,Painted Black Surround Grille,Power door mirrors,Power-Retractable Black Assist Steps,Rear step bumper,Rear Wheelhouse Liners,Spray-On Pickup Box Bed Liner w/AT4 Logo,Turn signal indicator mirrors,Winter Grille Cover,2 USB Ports,2 USB Ports (1st Row),2nd Row Dual USB Charge-Only Ports,4.2" Diagonal Color Display Driver Info Center,4G LTE Wi-Fi Hotspot Capable,8" Multicolor Driver Information Center,Apple CarPlay/Android Auto,Auto-dimming Rear-View mirror,Automatic Emergency Braking,Bed View Camera w/2 Trailer Camera Provisions,Compass,Compass Located In Instrument Cluster,Driver door bin,Driver vanity mirror,Floor-Mounted Center Console,Following Distance Indicator,Forward Collision Alert,Front Prem Floor Liners w/Removable Carpet Insert,Front reading lights,GMC Connected Access Capable,HD Rear Vision Camera,HD Surround Vision,Heated steering wheel,Illuminated entry,Inside Rearview Auto-Dimming Rear Camera Mirror,Lane Change Alert w/Side Blind Zone Alert,Multicolor 15" Diagonal Head-Up Display,OnStar & GMC Connected Services Capable,Outside temperature display,Overhead console,Passenger vanity mirror,Rear Cross Traffic Alert,Rear Prem Floor Liners w/Removable Carpet Insert,Rear reading lights,Rear seat center armrest,Tachometer,Telescoping steering wheel,Tilt steering wheel,Trip computer,Ultrasonic Front & Rear Park Assist,Upfitter Switch Kit (5),Voltmeter,Wireless Charging,Wireless Phone Projection,10-Way Power Driver Seat Adjuster w/Lumbar,10-Way Power Passenger Seat Adjuster w/Lumbar,Front Bucket Seats,Front Center Armrest,Heated & Ventilated Front Bucket Seats,Heated 2nd Row Outboard Seats,Heated Driver & Front Outboard Passenger Seats,Heated front seats,Heated rear seats,Perforated Leather-Appointed Front Seat Trim,Power passenger seat,Safety Alert Seat,Split folding rear seat,Ventilated front seats,Passenger door bin,Hitch Guidance w/Hitch View,In-Vehicle Trailering System App,Integrated Trailer Brake Controller,18" Machined Aluminum Wheels,20" Machined Aluminum Wheels,Alloy wheels,Wheels: 20" High Gloss Black Painted (LPO),Wheels: 20" Transit Aluminum,Deep-Tinted Glass,Power Front Passenger Windows w/Express Up/Down,Power Rear Windows w/Express Down,Power Sliding Rear Window w/Defogger,Variably intermittent wipers, LAMPS SMOKED AMBER LED ROOF MARKER (LED), BOSE SOUND SYSTEM PREMIUM 7-SPEAKER SYSTEM with Richbass woofer, ASSIST STEPS POWER-RETRACTABLE BLACK includes LED lighting, WIRELESS CHARGING, INTELLIBEAM AUTOMATIC HIGH BEAM ON/OFF, FOLLOWING DISTANCE INDICATOR, BED VIEW CAMERA camera in the CHMSL to show a view of the cargo bed display located in infotainment screen includes Two Trailer Camera Provisions, DRIVER INFORMATION CENTER ENHANCED 8" DIAGONAL MULTICOLOR DIGITAL DISPLAY includes analog speedometer and tachometer gauges, LANE CHANGE ALERT WITH SIDE BLIND ZONE ALERT, MULTI-COLOR 15" DIAGONAL HEAD-UP DISPLAY, LICENSE PLATE KIT FRONT, TRANSMISSION ALLISON 10-SPEED AUTOMATIC, GVWR 11 350 LBS. (5148 KG), SAFETY ALERT SEAT, JET BLACK WITH KALAHARI ACCENTS PERFORATED FRONT LEATHER SEAT TRIM, FRONT AND REAR PARK ASSIST ULTRASONIC, DRIVER ALERT PACKAGE I includes (UD5) Front and Rear Park Assist (UKC) Lane Change Alert with Side Blind Zone Alert and (UFG) Rear Cross Traffic Alert (Includes Perimeter Lighting., GOOSENECK / 5TH WHEEL PREP PACKAGE -- HITCH PLATFORM TO ACCEPT GOOSENECK OR 5TH WHEEL HITCH. Includes hitch platform with tray to accept ball stamped bed holes with removable caps installed and bed mounted 7-pin trailer harness (similar to UY2 harness)., WINTER GRILLE COVER, LPO 20" (50.8 CM) HIGH GLOSS BLACK PAINTED WHEELS LPO wheels will come with 4 aluminum 20" Transit Wheels from the factory with alignment specs set to 20" LPO wheel selected (dealer-installed), WINDOW POWER REAR SLIDING with rear defogger, CAYENNE RED TINTCOAT, UNIVERSAL HOME REMOTE, ENGINE BLOCK HEATER, UPFITTER SWITCH KIT (5) Provides 3-30 amp and 2-20 amp configurable circuits to facilitate installation of aftermarket electrical accessories. Kit with all required parts will be shipped loose with the truck for installation by the dealer or upfitter at customer expense. Installation instructions and technical assistance available at www.gmupfitter.com., AT4 PREFERRED PACKAGE includes (UVN) Bed View Camera (UVS) HD Surround Vision with Two Trailer View Camera Provisions (UG1) Universal Home Remote (A48) rear sliding power window (IOT) 8" diagonal Premium GMC Infotainment with navigation (UQA) Bose Premium Audio System (U01) Roof Marker Lamps and (K4C) Wireless Charging, SUNROOF POWER, AUDIO SYSTEM PREMIUM GMC INFOTAINMENT SYSTEM WITH NAVIGATION AND 8" DIAGONAL COLOR TOUCH-SCREEN includes multi-touch display AM/FM stereo Bluetooth streaming audio for music and most phones; featuring wireless Android Auto and Apple CarPlay capability for compatible phones advanced voice recognition in-vehicle apps personalized profiles for infotainment and vehicle settings. Includes greater memory. Includes (PZ8) Hitch Guidance with hitch view.), SEATS FRONT BUCKET with center console (STD), AT4 PREFERRED EQUIPMENT GROUP includes standard equipment, REAR CAMERA MIRROR INSIDE REARVIEW AUTO-DIMMING WITH FULL CAMERA DISPLAY, TECHNOLOGY PACKAGE includes (DRZ) Rear Camera Mirror and (UV6) Multi-color 15" Diagonal Head-Up Display Includes (UHS) 8" Digital Driver information Center., REAR AXLE 3.42 RATIO, REAR CROSS TRAFFIC ALERT, ENGINE DURAMAX 6.6L TURBO-DIESEL V8 B20-DIESEL COMPATIBLE (445 hp [332 kW] @ 2800 rpm 910 lb-ft of torque [1220 Nm] @ 1600 rpm) (Includes (K05) engine block heater.), AUTOMATIC EMERGENCY BRAKING, HD SURROUND VISION WITH TWO TRAILER VIEW CAMERA PROVISIONS provides the driver with an overhead view of the scene around the vehicle on a center stack display, EXHAUST BRAKE, PICKUP BED includes bed assist step (STD), DRIVER ALERT PACKAGE II includes (UEU) Forward Collision Alert (UFL) Lane Departure Warning (UHY) Automatic Emergency Braking (TQ5) IntelliBeam and (UE4) Following Distance Indicator Includes (HS1) Safety Alert Seat., GOOSENECK / 5TH WHEEL PACKAGE includes (Z6A) Gooseneck / 5th Wheel Prep Package. (Includes (UVN) Bed View Camera., WHEELS 20" TRANSIT ALUMINUM WHEELS for LPO 20" wheels and tires, AT4 PREMIUM PLUS PACKAGE includes (PDO) AT4 Preferred Package (PQB) Driver Alert Package I (PDJ) Driver Alert II (PYU) 20" (50.8 cm) machined aluminum wheels with high gloss Black accents (CF5) power sunroof (CWM) Technology Package and (VXW) AT4 high clearance step LPO, ALTERNATOR 220 AMPS, LANE DEPARTURE WARNING, TIRES LT275/65R20 ALL-TERRAIN BLACKWALL, FORWARD COLLISION ALERT, Tow Hitch, Running Boards/Side Steps, Locking/Limited Slip Differential, Four Wheel Drive, Tow Hooks, Power Steering, ABS, 4-Wheel Disc Brakes, Aluminum Wheels, Tires - Front All-Terrain, Tires - Rear All-Terrain, Conventional Spare Tire, Bed Liner, Daytime Running Lights, Fog Lamps, Heated Mirrors, Power Mirror(s), Integrated Turn Signal Mirrors, Power Folding Mirrors, Privacy Glass, Integrated Tailgate Step, AM/FM Stereo, MP3 Capability, Bluetooth Connection, Auxiliary Audio Input, Smart Device Integration, HD Radio, Satellite Radio, Requires Subscription, Satellite Radio, Requires Subscription, Bluetooth Connection, Bluetooth Connection, Smart Device Integration, WiFi Hotspot, Bucket Seats, Leather Seats, Power Driver Seat, Driver Adjustable Lumbar, Power Passenger Seat, Passenger Adjustable Lumbar, Heated Front Seat(s), Heated Front Seat(s), Cooled Front Seat(s), Mirror Memory, Seat Memory, Heated Rear Seat(s), Pass-Through Rear Seat, Floor Mats, Floor Mats, Leather Steering Wheel, Heated Steering Wheel, Steering Wheel Audio Controls, Adjustable Steering Wheel, Power Windows, Power Windows, Power Windows, Power Door Locks, Keyless Entry, Power Door Locks, Keyless Start, Remote Engine Start, Cruise Control, Security System, MP3 Capability, Auxiliary Audio Input, MP3 Capability, Auxili