The 2021 GMC Sierra Diesel receives quite a few updates and changes, including new colors, new wheel availability, new standard features, and new packaging contents for both light duty (1500) and heavy duty (2500HD, 3500HD) models.
2021 GMC Sierra Diesel 1500 Changes
Model Line
- Deletion of 2WD Standard Bed Crew Cab model (TC10743)
- Double Cab models no longer available on SLT and AT4
Exterior
- Addition of four new exterior colors:
- Ebony Twilight Metallic
- Cayenne Red Tintcoat
- Hunter Metallic
- Brownstone Metallic
- Deletion of four exterior colors:
- Deep Mahogany Metallic
- Red Quartz Tintcoat
- Smokey Quartz Metallic
- Carbon Black Metallic
- Addition of the following LPO-level items:
- AT4 high clearance step
- 22-inch Multi-spoke Polished wheels (SES)
- Deletion of manual tailgate function with lift assist
- GMC MultiPro Tailgate is now available on SLE (3SA) and AT4 (3SB) models
Interior
- Addition of wireless Apple CarPlay and Android Auto
- Addition of premium floor liners with removable carpet inserts
- Now standard on AT4 models
- Sirius XM Radio is standard on SLE (3SA) and Elevation (3SB) models
- Dark Walnut / Slate is no longer available on Elevation Trim
- Sunroof no longer available on SLE (3SA) and AT4 (3SB) models
- Front 40/20/40 split-bench with covered armrest storage is now standard on base Sierra (1SA) models
- For the 2020 model year, the covered armrest storage was only available with models equipped with the turbocharged 2.7-liter L3B four-cylinder engine
- Bucket seats are now available as an option on all Elevation (3SB) models
- For the 2020 model year, the front bucket seat option was only available for models equipped with the Elevation Convenience Package
- Improved towing technology features
Mechanical
- Addition of LT265/60R20 MT blackwall Goodyear Wrangler Territory tires
- Increased maximum tow ratings for models powered by turbocharged 2.7L I-4 L3B gasoline engine and 3.0L I-6 LM2 turbo-diesel Duramax engine
See detailed 2021 GMC Sierra 1500 changes, updates and new features here: 2021 GMC Sierra 1500 change log.
The updates and changes described here are specific to the U.S. market and may differ for other markets.
2021 GMC Sierra Diesel HD Changes
Exterior
- Deletion of two exterior color options
- Dark Sky Metallic
- Red Quartz Tintcoat
- Addition of three exterior color options
- Ebony Twilight Metallic
- Cayenne Red Tintcoat
- Hunter Metallic
- Deletion of 18-inch (45.7 cm) 6-spoke machined aluminum extended wheels with high gloss Black accents
- Addition of AT4 high clearance step (LPO-level item)
- Addition of power-retractable Assist steps with stainless steel accents
- Includes LED lights
- Addition of new, high gloss Black mirror caps for AT4 models
- Addition of LT275/70R18, mud-terrain, blackwall tires (QG3)
- For 2500HD models only, not available for 3500HD models
- Addition of 18-inch (45.7 cm) machined aluminum wheel with Dark Grey metallic accents (PXD)
- Addition of 20-inch (50.8 cm) high gloss Black painted aluminum wheels (RTJ)
- Addition of Bedside Storage, right hand and left hand side
- Addition of Tie-Downs option – includes 4
- Addition of 20-inch Transit wheels for 20-inch LPO-level wheels
- Addition of 20-inch machined aluminum wheel wheels with new finish and bright Silver accents
- Addition of 20-inch wheels with new finish, machined aluminum with high gloss Black accents (SKX)
- Only available for Denali and AT4 models
- LPO-level item
- Addition of 20-inch (50.8 cm) multi-dimensional Chrome aluminum wheels (SKW)
- Only available for Denali models
- LPO-level item
Interior
- Deletion of front 40/20/40 split-bench seat
- Deletion of single USB Port
- Addition of Premium floor liners with removable carpet inserts
- Front and rear
- Addition of inside rearview auto dimming mirror with partial video display
- Addition of Bed View Camera in the CHMSL to show a view of the cargo bed
- Display located in rearview mirror
- Front 40/20/40 split-bench seat with upper covered armrest storage is now standard on base (1SA) Sierra HD models
- For the 2020 model year, the 40/20/40 split-bench seat was standard
- SiriusXM is now standard on SLE models and available on base models
- For the 2020 model year, SiriusXM was only standard on SLT, AT4, and Denali models
Mechanical
- Standard tailgate is now available on SLE models, remains standard on base models, and is no longer available for SLT, AT4, or Denali models.
- For the 2020 model year, the standard tailgate was standard on base and SLE models, and available on all other models
- Deletion of manual tailgate function with lift assist
- GMC MultiPro Tailgate is now standard on SLE models
- For the 2020 models, SLE models came standard with
- Gooseneck / 5th Wheel Package is not available on Denali models
- Gooseneck / 5th Wheel Prep Package is now a free flow option
- Change applies to Denali models only
- ProGrade Trailering System no longer includes:
- EZ Lift and power lock and release tailgate
- Still includes:
- Hitch Guidance with Hitch View
- In-vehicle Trailering App
- 8-inch diagonal Premium GMC Infotainment System
- HD Rear Vision Camera
- USB Ports (Instrument Panel with bench seat)
- SiriusXM with 360L
- HD Radio
- Only available for SLE models
Packaging
- Addition of the AT4 Premium Plus Package, which is exclusive to AT4 models and includes:
- Driver Alert Package I:
- Front and Rear Park Assist
- Lane Change Alert with Side Blind Zone Alert
- Rear Cross Traffic Alert
- Perimeter Lighting
- Driver Alert II:
- Technology Package:
- Rear Camera Mirror
- Multicolor 15-inch Diagonal Head-Up Display
- 20-inch (50.8 cm) machined aluminum wheels with high gloss Black accents (PYU)
- Can be upgraded to:
- 20-inch High gloss Black painted wheels (S6L)
- (LPO-level item)
- 20-inch high gloss Black aluminum wheels with machined accents (SKX)
- (LPO-level item)
- 20-inch High gloss Black painted wheels (S6L)
- Can be upgraded to:
- Power sunroof
- AT4 high clearance step (LPO-level item)
- AT4 high clearance step can be substituted with Black Sport Step (LPO-level item), but no other assist steps are available
- Driver Alert Package I:
- Addition of Denali Black Diamond Edition, which is exclusive to Denali models and includes:
- Auxiliary Trailer Camera
- MultiPro Audio System by Kicker
- Premium front and rear floor liners with removable carpet insert
- Trailer tire pressure monitor sensors
- Power-retractable assist steps with LED perimeter lighting
- 2-inch (50.8 cm) high gloss Black painted aluminum wheels (RTJ)
- Requires:
- 4WD model configuration
- Ebony Twilight Metallic exterior color
- 6.6-liter Duramax Turbo-Diesel L5P V8 engine
- Denali Ultimate Package
- Technology Package
- Sunroof
- Not available with any LPO wheels
- Addition of the X31 Off-Road and Protection Package, which is available on
- Off-Road suspension with Twin-tube Rancho shocks
- Hill Descent Control
- Skid plates (transfer case and oil pan)
- Spray-on bedliner
- All-weather floor liners (LPO-level item)
- X31 badge (replaces “4X4” badge on bed)
- SLE models include:
- 18-inch machined aluminum wheel with Dark Grey metallic accents (PXD) with LT275/70R18E all-terrain, blackwall tires
- Wheels and tires may be upgraded to 20-inch machined aluminum wheel (Q7R) with bright Silver accents and LT275/65R20 all-terrain, blackwall tires
- Requires Crew Cab or Double Cab 4WD model
- Not available with pickup bed delete
- 18-inch machined aluminum wheel with Dark Grey metallic accents (PXD) with LT275/70R18E all-terrain, blackwall tires
- SLT models include:
- 20-inch machined aluminum wheel with bright Silver accents (Q7R) and LT275/65R20 all-terrain, blackwall tires
- Requires a 4WD model
- Not available with pickup bed delete
- Addition of 1SA Safety Confidence Package, which is available on base Sierra HD models and includes:
- Forward Collision Alert
- Automatic Emergency Braking
- Cruise Control
- Steering wheel audio controls
- Driver Information Center
- Not available with pickup bed delete
- Technology Package no longer includes Bed View Camera or HD Surround Vision
- New RPO code designation for SLT Premium Plus Package (PDB), which includes:
- SLT Convenience Package:
- Bucket seats with center console
- Ventilated front seats
- Rear sliding power window
- Universal Home Remote
- USB Ports (Inside Console with bucket seats)
- 2 USB ports with auxiliary input
- Roof Marker Lamps
- Crew Cab models also include rear heated seats
- SLT Preferred Package:
- 8-inch diagonal Premium GMC Infotainment with navigation
- Bose Premium Audio System
- Wireless Charging
- Driver Alert Package I:
- Front and Rear Park Assist
- Lane Change Alert with Side Blind Zone Alert
- Rear Cross Traffic Alert
- For SLE models:
- Includes Perimeter Lighting
- Not available with pickup bed delete
- Requires trailer mirrors
- Requires SLE Convenience Package:Â
- Dual climate control
- 10-way power driver seat including power lumbar
- Heated driver and passenger seats,
- Heated steering wheel
- Manual tilt/telescoping steering column
- Rear-window defogger
- Keyless Open and Start
- Steering column lock
- Remote Start
- Content theft alarm
- Front 40/20/40 split-bench with underseat storage on Crew Cab and Double Cab models
- 2 charge-only USB ports for second row
- Cargo bed LED lighting
- Rear auxiliary 12-volt power outlet
- Fog lights
- Roof Marker Lamps
- Rear wheelhouse liners
- Included with SLE Value Package:
- Available for Crew Cab and Double Cab models
- Includes SLE Convenience package and (CGN) spray-on bedliner
- Not available with:
- Remote Start Package
- Pickup bed delete
- Note: Roof Marker Lamps are not available with vehicles that need to meet California state emissions requirements
- For SLT models:
- Includes Perimeter Lighting
- Included with SLT Premium Package or Texas Edition SLT Premium Package
- Not available with (ZW9) pickup bed delete
- For AT4 models:
- Includes Perimeter Lighting
- Included with AT4 Premium Plus Package
- 6-inch rectangular, cab length Chrome assist steps
- Available for Crew Cab models only
- 6-inch Chrome rectangular tubular assist step (LPO-level item)
- Available for Double Cab models only)
- Spray-on bedliner
- No substitutions to the above content may be made
- Not available with pickup bed delete or Texas SLT Premium Package
- For the 2020 model year, the package included
- SLT Convenience Package:
- New RPO code designation for Texas Edition SLT Premium Plus Package, which includes:
-
- SLT Convenience Package
- SLT Preferred Package
- Driver Alert Package I
- 6-inch rectangular, cab length Chrome assist steps
- (Crew Cab models only)
- 6-inch Chrome rectangular tubular assist step, LPO (Double Cab models only)
- Spray-on bedliner
- Texas Edition badging
- No substitutions may be made to the above content
- Not available with pickup bed delete or SLT Premium Package
- Only available for dealers located in:
- Arkansas
- Louisiana
- New Mexico
- Oklahoma
- Texas
-
- SLE Convenience Package no longer includes EZ Lift power lock and release tailgate, still includes:
- Dual climate control
- 10-way power driver seat including power lumbar
- Heated driver and passenger seats
- Heated steering wheel
- Manual tilt/telescoping steering column
- Rear-window defogger
- Keyless Open and Start
- Steering column lock
- Remote Start
- Content theft alarm
- Front 40/20/40 split-bench with underseat storage
- On Crew Cab and Double Cab models
- 2 charge-only USB ports for second row
- Cargo bed LED lighting
- Rear auxiliary 12-volt power outlet
- Fog lights
- Roof Marker Lamps
- Rear wheelhouse liners
- Included with SLE Value Package, which also includes:
- Spray-on bedliner
- Only available for Crew Cab and Denali Cab models
- Not available with:
- Remote Start Package
- Pickup bed delete
- Note: Roof Marker Lamps are not available with vehicles that need to meet California state emissions requirements
- SLT Preferred Package now includes:
- Bed View Camera
- HD Surround Vision with Two Trailer View Camera Provisions
- Also includes:
- 8-inch diagonal Premium GMC Infotainment with navigation
- Bose Premium Audio System
- Wireless Charging
- Requires SLT Convenience Package
- Included with SLT Premium Package or Texas Edition SLT Premium Package
- AT4 Preferred Package now includes:
- Bed View Camera
- HD Surround Vision with Two Trailer View Camera Provisions
- Also includes:
- Universal Home Remote
- Rear sliding power window
- 8-inch diagonal Premium GMC Infotainment with navigation
- Bose Premium Audio System
- Roof Marker Lamps
- Wireless Charging
- Included with AT4 Premium Package
- Note: Roof Marker Lamps are not available with vehicles that need to meet California state emissions requirements
See detailed 2021 GMC Sierra HD changes, updates and new features here: 2021 GMC Sierra HD change log.
The updates and changes described here are specific to the U.S. market and may differ for other markets.
Discussion
Discuss the 2021 GMC Sierra Diesel in our GMC forum.
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