2003 GMC Sierra 2500HD SLE Extended Cab 4×4 8.1L 6-Speed

Listing Details

• Chassis: 1GT120E89FF556309
• 61k Miles
• Turbodiesel 6.6-Liter Duramax V8
• Six-Speed Automatic Transmission
• Dual-Range Transfer Case
• Iridium Metallic Paint
• Dune Perforated Leather Upholstery
• 20" Chrome 10-Spoke Wheels
• Sunroof
• Power-Sliding Rear Window
• Tonneau Cover
• Running Boards
• Heated Front Seats
• Bose Sound System
• Navigation

This 2015 GMC Sierra 2500HD Denali crew cab pickup was purchased new by the seller and has 61k miles. The truck is finished in Iridium Metallic (GXG) over Dune perforated leather and is powered by a turbodiesel 6.6-liter Duramax V8 linked to a six-speed automatic transmission and a dual-range transfer case. Equipment includes a sunroof, a power-sliding rear window, running boards, front and rear parking sensors, a tonneau cover, heated and ventilated front bucket seats, a heated steering wheel, remote start, a Bose sound system, and navigation. This K2XX Sierra 2500HD is offered by the seller with the owner’s manual and a clean Pennsylvania title in the seller’s name. The crew-cab bodywork is finished in Iridium Metallic (GXG), and exterior equipment includes a sunroof, a power-sliding rear window, running boards, front and rear parking sensors, a tonneau cover, a bedliner, moveable cargo-bed tie-downs, recovery hooks, and projector-style headlights. A dent is noted on the left-rear quarter panel, and the Carfax report lists “minor damage” to the rear of the truck in September 2015. The 20″ chrome 10-spoke wheels are mounted with Goodyear tires. The truck is equipped with variable-assist power steering in addition to Stabilitrack stability control, hill-start assist, a trailer brake, and four-wheel disc brakes. The cabin is upholstered in Dune perforated leather, and interior appointments include heated and ventilated front bucket seats, remote start, a Bose sound system, a navigation system, a CD stereo, automatic climate control, and cruise control. The heated four-spoke steering wheel frames a 140-mph speedometer, a 5k-rpm tachometer, and supplementary gauges. The digital odometer indicates 61k miles, all of which were added under current ownership. The seller notes one of the tire pressure monitor sensors does not work right, and a related indicator light is illuminated on the dashboard.The turbodiesel 6.6-liter Duramax V8 was factory rated at 397 horsepower and 765 lb-ft of torque.

Listing Details

• Chassis: 3GTU1NER3HG513771
• 47k Miles
• 5.3-Liter V8
• eAssist Mild-Hybrid System
• Eight-Speed Automatic Transmission
• Limited-Slip Differential
• Onyx Black Paint
• Jet Black Leather Upholstery
• Chromed 20" Six-Spoke Alloy Wheels
• LED Headlights
• Running Boards
• Hitch Receiver
• Power-Sliding Rear Window
• Front & Rear Parking Sensors
• Folding Tonneau Cover
• Dual-Zone Automatic Climate Control
• Power-Adjustable Front Bucket Seats
• Front-Seat Heat & Ventilation
• Split-Folding Rear Bench
• Bose Sound System
• Navigation
• CD Stereo
• Wireless Phone Charging
• Heated Steering Wheel
• Remote Start
• Window Sticker
• Clean Carfax Report

This 2017 GMC Sierra 1500 SLT was purchased new by the seller and is an eAssist example with a mild-hybrid system that works in conjunction with its 5.3-liter V8 and eight-speed automatic transmission. Finished in Onyx Black over Jet Black leather upholstery, the truck is equipped with LED headlights, chromed 20″ alloy wheels, regenerative four-wheel disc brakes, a limited-slip differential, a rear step bumper, parking sensors, a power-sliding rear window, side steps, a tonneau cover, and a hitch receiver. Inside, heated and ventilated front seats are accompanied by dual-zone automatic climate control, wireless phone charging, power-adjustable pedals, a 110-volt accessory outlet, a heated steering wheel, remote start, a trailer-brake controller, Bose audio, a CD stereo, and navigation. This Sierra 1500 SLT eAssist has 47k miles and is now offered at no reserve with a window sticker, two keys, a clean Carfax report, and a clean California title in the seller’s name. The truck is finished in Onyx Black with chrome bumpers, the rear of which features corner steps. Exterior details include automatic grille shutters, LED headlights, power-folding side mirrors, chrome side steps, front and rear parking sensors, tinted windows, a spray-on bedliner, a folding soft tonneau cover, and a hitch receiver. The right-side mirror’s power-folding feature does not work, and a dent in the front bumper is depicted in the gallery. Chrome-plated 20″ six-spoke alloy wheels are wrapped in 275/55 Michelin LTX M/S² tires. The truck is equipped with variable-assist power steering in addition to four-wheel disc brakes and a trailer-brake controller. The heated, ventilated, and power-adjustable front bucket seats are upholstered in Jet Black leather, and the split-folding rear bench is trimmed to match. Additional appointments include dual-zone automatic climate control, power-adjustable pedals, driver-seat position memory, remote start, woodgrain trim, a CD stereo, a Bose sound system, navigation, cruise control, internet connectivity, wireless phone charging, an auto-dimming rearview mirror, and a 110-volt outlet in the center console as well as a power-sliding rear window with a defogger. The heated and leather-wrapped multifunction steering wheel frames a 140-mph speedometer, a tachometer, and gauges for coolant temperature, oil pressure, fuel level, and voltage as well as a central digital display. The digital odometer indicates 47k miles, all of which were driven under current ownership. The 5.3-liter V8 was factory rated at 355 horsepower and 383 pound-feet of torque and is equipped with direct injection, variable valve timing, and Active Fuel Management cylinder deactivation. It is supplemented with a mild-hybrid system comprised of an induction motor rated at 13 horsepower and 44 lb-ft of torque along with a 0.45-kWh lithium-ion battery that is charged through regenerative braking. The engine oil was most recently changed in March 2025.

Listing Details

• Chassis: 1GT120E80FF645430
• 20k Miles
• 6.6L Duramax Turbodiesel V8
• Six-Speed Automatic Transmission
• 3.73:1 Locking Rear Differential
• Onyx Black Paint
• Jet Black Leather Upholstery
• 20" American Racing Wheels w/35" Tires
• Lifted Ride Height
• Power-Retractable Side Steps
• Heated & Ventilated Front Seats
• 8" Touchscreen w/Rearview Camera
• Bose Sound System
• Exhaust Brake & Block Heater
• Clean Carfax Report

This 2015 GMC Sierra 2500HD Denali is a crew-cab 4×4 pickup that was registered with one owner in Florida until 2024, and it was ordered with a 6.6-liter Duramax turbodiesel V8, an Allison 1000 six-speed automatic transmission, and an automatic locking rear differential with 3.73:1 gearing. Finished in Onyx Black over Jet Black leather, it was further optioned with a sunroof, an engine block heater, and the Driver Alert package of driving aids. The truck also has a lifted ride height, 20″ American Racing wheels, 35″ tires, power-retractable side steps, heated and ventilated front seats, a rearview camera, touchscreen infotainment, and a Bose sound system. This Sierra 2500HD has 20k miles and is offered by the selling dealer with owner’s manuals, two keys, a clean Carfax report, and a clean New Jersey title. Exterior details include LED signature lighting, power-folding and heated towing mirrors, a rear bumper with corner steps, and a spray-in bedliner. Flaws around the vehicle are pictured in close-up photos shown in the gallery below. The American Racing 20″ wheels are mounted with 35×12.50″ Gladiator X Comp A/T tires. The ride height is lifted with Pro Comp components, and the four-wheel disc brakes have 14″ rotors and StabiliTrak with Trailer Sway Control. The heated and ventilated power-adjustable front seats are trimmed in Jet Black leather, and the five-passenger cab has a sunroof, a power-operated sliding rear window, a 110-volt power outlet, a six-speaker Bose sound system with a subwoofer, and an 8″ touchscreen. The heated steering wheel frames an 8″ configurable display flanked by the instruments, and a trailer brake controller is fitted on the left side of the dashboard. The driver is aided by a rearview camera, power-adjustable pedals, parking sensors, lane departure warning, forward collision alert, and a Safety Alert driver’s seat. The odometer indicates 20k miles. Factory rated at 397 horsepower and 765 lb-ft of torque, the 6.6-liter Duramax turbodiesel V8 has a block heater, remote start, and an exhaust brake, and it sends power to the rear or all four wheels through an Allison six-speed automatic transmission, an electronic dual-range transfer case, and an Eaton automatic locking rear differential with 3.73:1 gearing.

Listing Details

• Chassis: 1GT12UE82GF258144
• 101k Miles
• Replacement Turbodiesel 6.6L V8
• Narrow-Journal Crankshaft
• Wagler Connecting Rods
• Alternate-Firing-Order Camshaft
• Compound Turbo Setup
• Six-Speed Allison Automatic Transmission
• Dual-Range Transfer Case
• Locking Rear Differential
• Onyx Black Paint
• Jet Black Leather Upholstery
• 22" American Force Wheels
• Cognitio Upper Control Arms
• Fox Shocks
• Wilwood Six-Piston Disc Brakes
• Wehrli Custom Traction Bars
• Heated & Ventilated Front Seats
• Lock'er Down Console Safe
• Smartphone Integration
• Window Sticker & Build Sheet
• Clean Carfax Report

This 2016 GMC Sierra 2500HD Denali crew cab pickup is powered by a replacement turbodiesel 6.6 Duramax V8, which was built by SoCal Diesel with a new GM block and later rebuilt by Wagler Competition. It features a narrow-journal crankshaft, Wagler connecting rods, high-performance pistons, an alternate-firing-order camshaft, CNC-ported heads, a compound turbo setup, an Exergy Performance fuel pump, and 150%-over injectors. The six-speed Allison automatic transmission was rebuilt in 2017 with various billet components and again in 2024, and it is paired with a dual-range transfer case and a locking rear differential. Additional modifications include Cognito upper control arms, Fox shocks, Wehrli Custom traction bars, a leveling kit, Wilwood six-piston disc brakes, and 22″ American Force wheels. The Onyx Black exterior is joined by a Jet Black perforated leather interior, and further details include a folding tonneau cover, a bed liner, heated and ventilated front bucket seats, a Lock’er Down console safe, remote start, dual-zone automatic climate control, an infotainment system with smartphone integration, and JL Audio components. This K2XX Sierra 2500HD was purchased new by the seller and has 101k miles. It is now offered with the window sticker, the owner’s manual, a build sheet, service records, spare parts, a clean Carfax report, and a clean Florida title in the seller’s name. The crew-cab bodywork is finished in Onyx Black (GBA), and exterior equipment includes a power-sliding rear window, running boards, front and rear parking sensors, an Extang folding tonneau cover, a bed liner, moveable cargo-bed tie-downs, recovery hooks, tinted windows, and projector-style headlights. The seller tells us that a ceramic coating was applied in 2025. The suspension system has Cognito upper control arms, Fox shocks, Wehrli Custom traction bars, and a leveling kit. The steering system features Kryptonite tie rods, which were installed in 2024, along with a pitman arm and idler arm support kit. The four-wheel disc brakes have been modified with a Wilwood six-piston big-brake kit, and a Wehrli Custom master cylinder cover has been fitted. The 22″ American Force wheels are mounted with Nitto NT420V tires, which were said to have been installed in June 2023. The cabin is upholstered in Jet Black perforated leather. Interior appointments include heated and ventilated front bucket seats, remote start, a Lock’er Down console safe, a Bose sound system, dual-zone automatic climate control, and an 8″ infotainment screen with navigation, Apple CarPlay, and Android Auto capability. The audio system has been modified with a JL Audio 300-watt amplifier and 10″ subwoofer. The heated steering wheel frames a 140-mph speedometer, a 6k-rpm tachometer, and supplementary gauges. An Edge CTS3 Insight monitor is mounted to the windshield. The digital odometer indicates 101k miles. The replacement turbodiesel 6.6 Duramax V8 was built by SoCal Diesel in 2017, and it was rebuilt in March 2024 by Wagler Competition. It has a billet stock-stroke narrow-journal crankshaft with Wagler connecting rods, high-performance pistons, a Stage 3 alternate-firing-order camshaft, Stage 2 CNC-ported heads, and a compound turbo setup featuring a Forced Inductions S485 V5 unit and Wehrli Custom components. Additional modifications include:

• Exergy Performance 12mm stroker CP3 pump and 150%-over injectors
• PureFlow AirDog II lift pump
• Mishimoto intercooler
• L5P-style oil cooler
• 400amp Powermaster alternator
• Wehrli Custom air intake
• Flowpro straight-piped exhaust system

A fluids service was performed in preparation for the sale. The six-speed Allison automatic transmission was rebuilt in 2017 with various billet components and again in 2024, when an SFI-approved billet flywheel was installed. It is paired with a dual-range transfer case and a locking rear differential, and further details include a Mishimoto transmission cooler and a Mag-Hytech transmission pan and rear differential cover.