2021 GMC Sierra 4WD AT4Fuel Economy & MPG Ratings
Trim Comparison
| Trim | Engine | City | Hwy | Combined | Fuel Cost/yr |
|---|---|---|---|---|---|
| Automatic 10-spd | Diesel Diesel | 22 | 26 | 24 | $3,500 |
| Automatic 8-spd | Regular | 16 | 21 | 18 | $3,750 |
| Automatic 10-spd | Regular | 16 | 21 | 18 | $3,750 |
| Automatic 10-spd | Premium | 15 | 19 | 17 | $4,800 |
| Automatic 10-spd | Regular | 15 | 21 | 17 | $3,950 |
| Automatic 8-spd | Regular | 14 | 20 | 16 | $4,200 |
| Automatic 10-spd | Premium | 14 | 19 | 16 | $5,100 |
| Automatic 6-spd | Regular | 14 | 18 | 16 | $4,200 |
Based on gasoline at $3.67/gal, 15,000 miles/year
vs. average new vehicle
Environment
- CO₂ Tailpipe Emissions
- 430 g/mile
- Annual Petroleum Consumption
- 14.9 barrels
Specifications
- Engine
- 6.2L 8-cyl
- Transmission
- 10-speed Automatic
- Drivetrain
- 4WD
- Body Style
- Pickup Truck
- GVWR
- Class 2-3 (6,001–10,000 lbs)
Source: EPA fuel economy data & NHTSA vPIC. Specifications reflect the most common trim configuration.
Engine & Efficiency Details
Source: EPA fueleconomy.gov
- Engine Size
- 3L, 6-cylinder
- Efficiency Tech
- Auto Start-Stop
- Fuel Type
- Diesel
Recall History
Source: NHTSA✓No recalls reported for this vehicle.
Owner-Reported Problems482 complaints
Source: NHTSANHTSA has received 482 owner complaints for the 2021 GMC Sierra 4WD AT4. Top reported issues include engine, power train and electrical system. The data below is sourced from consumer complaints filed directly with NHTSA.
Problems by System / Component
2021 GMC Sierra 4WD AT4 problems by category: Engine: 291 complaints, Power Train: 114 complaints, Electrical System: 65 complaints, Fuel System: 29 complaints, Steering: 29 complaints, Brakes: 22 complaints, Advanced Safety (ADAS): 13 complaints, Structure: 10 complaints.
Sample Owner Complaints
Complaint data is sourced from the NHTSA Complaints Database. Reports are filed by vehicle owners and may not reflect confirmed defects. Last updated via NHTSA API.