2021 GMC Sierra 2WDFuel Economy & MPG Ratings

Diesel Standard Pickup Trucks 2WDRear-Wheel Drive
City
23
MPG
Highway
30
MPG
Combined
26
MPG

Trim Comparison

Automatic 10-spd
Diesel Diesel
City
23
Hwy
30
Comb
26
Fuel cost: $3,250/yr
Automatic 8-spd
Regular
City
20
Hwy
23
Comb
21
Fuel cost: $3,200/yr
Automatic 8-spd
Regular
City
20
Hwy
23
Comb
21
Fuel cost: $3,200/yr
Automatic 8-spd
Regular
City
17
Hwy
23
Comb
19
Fuel cost: $3,550/yr
Automatic 8-spd
Regular
City
15
Hwy
22
Comb
17
Fuel cost: $3,950/yr
Automatic 6-spd
Regular
City
16
Hwy
21
Comb
17
Fuel cost: $3,950/yr
Automatic 6-spd
Regular
City
15
Hwy
21
Comb
17
Fuel cost: $3,950/yr
Automatic 6-spd
Regular
City
14
Hwy
21
Comb
16
Fuel cost: $4,200/yr
Automatic 6-spd
Gasoline or E85 FFV
City
15
Hwy
19
Comb
16
Fuel cost: $4,200/yr
Annual Fuel Cost
$3,250

Based on gasoline at $3.67/gal, 15,000 miles/year

5-Year Fuel Savings
$-4,250

vs. average new vehicle

EPA Fuel Economy Score: 5/10
GHG Score: 5/10

Environment

CO₂ Tailpipe Emissions
392 g/mile
Annual Petroleum Consumption
13.7 barrels

Specifications

Engine
5.3L 8-cyl
Transmission
6-speed Automatic
Drivetrain
RWD
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: NHTSA

NHTSA has received 482 owner complaints for the 2021 GMC Sierra 2WD. 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

Engine
291
Power Train
114
Electrical System
65
Steering
29
Fuel System
29
Brakes
22
Advanced Safety (ADAS)
13
Structure
10

2021 GMC Sierra 2WD problems by category: Engine: 291 complaints, Power Train: 114 complaints, Electrical System: 65 complaints, Steering: 29 complaints, Fuel System: 29 complaints, Brakes: 22 complaints, Advanced Safety (ADAS): 13 complaints, Structure: 10 complaints.

7
Crashes Reported
12
Fires Reported
2
Injuries Reported

Sample Owner Complaints

EngineFiled: 04/09/2026ODI#11730203
See attached document for complaint. INFORMATION, DETAILS, COMMENTS, DATES, AND NUMBERS ON RECALL 20211500 DENALI Recall Vehicle Information: All models of GM's with 6.2L gas engine (My personal truc…
Power TrainFiled: 04/28/2025ODI#11657385
See attached vehicle repair orders/Carfax/vehicle registration. The trucks transmission has been slipping/jerking hard since I pulled off the lot at dealer ship. Its burning oil no leaks has bee…
Power TrainFiled: 03/12/2025ODI#11647961
[XXX], I PURCHASED A 2021 GMC SIERRA 1500 FROM FAULKNER CHEVROLET IN BETHLEHEM, PA. I TEST DROVE THE VEHICLE BEFORE PURCHASE AND IT SHOWED NO INDICATION OF ANY MECHANICAL ISSUES THAT I WAS ABLE TO DET…

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.

Related

GMC Sierra 2WD MPG History
See how this model's fuel economy changed by year

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