Research · Standard Pickup Trucks 2WD

2021 GMC SierraRecalls, problems, MPG & safety

NHTSA lists 7 safety recalls and 599 owner complaints for the 2021 GMC Sierra. Most complaints involve engine (323) and power train (145). The EPA rates it 16–26 mpg combined, and NHTSA gives it 4–5 stars overall.

Combined MPG
16–26mpg
EPA · 12 versions
NHTSA overall
4–5of 5 stars
NCAP crash tests
Safety recalls
7campaigns
Latest Feb 2026
Owner complaints
599
Top: engine
Fuel cost / yr
$3,050est.
EPA estimate, best version
01 —Recalls

Safety recalls

7 NHTSA campaigns · applies to some vehicles, check your VIN

Power train: software

Free remedy

General Motors, LLC is recalling certain 2020 Chevrolet Silverado 2500, 3500, GMC Sierra 2500, 3500, and 2020-2022 Chevrolet Silverado 1500 and GMC Sierra 1500 vehicles that may have been repaired incorrectly under recall 24V797. The transmission control valve may fail and cause the rear wheels to lock up.

Power trainReported Feb 13, 2026NHTSA 26V083000

Engine and engine cooling: hard parts internal

Free remedy

General Motors LLC (GM) is recalling certain 2021-2024 Cadillac Escalade and Escalade ESV, Chevrolet Silverado 1500, Suburban, and Tahoe, GMC Sierra 1500, Yukon, and Yukon XL vehicles equipped with a 6.2L V8 gas engine. The connecting rod and/or crankshaft engine components may have manufacturing defects that can lead to engine damage and engine failure.

Engine and engine coolingReported Apr 24, 2025NHTSA 25V274000

Power train: software

Free remedy

General Motors, LLC (GM) is recalling certain 2020-2022 Chevrolet Silverado 1500, 2500, 3500, GMC Sierra 1500, 2500, 3500, 2021 Cadillac Escalade, Escalade ESV, Chevrolet Tahoe, Suburban, GMC Yukon, and Yukon XL vehicles equipped with diesel engines. The transmission control valve may fail and cause the rear wheels to lock-up.

Power trainReported Oct 24, 2024NHTSA 24V797000
Data from NHTSA Recalls API · synced Nov 3, 2026 · All recall detailsNHTSA vehicle page
02 —Complaints

Owner complaints by component

599 complaints filed with NHTSA · Dec 2020 – Oct 2026
  1. Engine323
  2. Power train145
  3. Electrical system76
  4. Engine and engine cooling49
  5. Fuel/propulsion system41
  6. Steering34
  7. Service brakes24
  8. Structure13
  9. Suspension10

Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.

By model year

Complaints for each Sierra model year we’ve synced.

View as table
Model yearNHTSA complaints
2020495
2021599
2022603
2023506
2024386
2025136
202681
Crashes reported
6
Fires reported
6
Injuries reported
3
Deaths reported
0
Data from NHTSA Complaints API · synced Nov 3, 2026 · Full problem breakdownNHTSA vehicle page
03 —Common problems

What owners report most

Verbatim excerpts from NHTSA complaints, by component

Engine

323 reports5 fires
“I have repeatedly experienced a noticeable exhaust odor inside the cab while operating the vehicle\. The condition is particularly pronounced during cold weather when the vehicle is idling\. Under these circumstances, the exhaust smell inside the passenger compartment is distinct and concerning\. I have taken the vehicle to two separate General Motors dealerships in an effort to identify and resolve this issue\. On both occasions, I was advised that the vehicle was fine\. Despite these visits, the problem remains unresolved, and I continue to experience exhaust fumes inside the cab under the conditions described above\. My concern is that exhaust gases may be entering the passenger compartment, potentially exposing the driver and passengers to harmful emissions, including carbon monoxide\. Because carbon monoxide cannot be detected by smell, the presence of an exhaust odor does not establish whether carbon monoxide is present or at what concentration\. However, the recurring odor warrants a thorough investigation to determine its source and whether a potentially hazardous condition exists\. I am concerned that the issue may not be adequately identified during…”
Owner complaint to NHTSAFiled Oct 29, 2026Unknown or other, EngineODI 11774349

Power train

145 reports
“My 2021 GMC 1500 Sierra has the 6.2L motor that has significant known issues with catastrophic engine failure involving the camshaft and lifters. The engine in my truck has suffered the same failure but for some reason my VIN is not included in the recall of nearly 600,000 GMC trucks. I called GMC Customer Service and was told bluntly the recall was VIN specific and I would have to bear the 14,000 dollar repair. This is unacceptable since GMC is under federal investigation for knowingly and negligently manufacturing a flawed motor.”
Owner complaint to NHTSAFiled Oct 20, 2026Power train, Engine, Fuel/propulsion systemODI 11772316

Electrical system

76 reports3 fires
“The infotainment system inadvertently shuts down and restarts which creates a unsafe situations while using the navigation system, backing up using the backup camera and while trailering. In a 30 mile drive it might do it 10 times and it might do it 30 times and eventually it doesnt restart until the vehicle is shut off. Each time it does it, it starts with the screen locking up which has resulted in me backing into my boat trailer 3 times while backing up to put the trailer on the hitch and numerous near misses with pedestrians and other vehicles in parking lots. Research on the internet indicates it is a known issue across several GMC platforms and has been since 2016. I took my truck to the dealer, they did a software update which was unsuccessful, then they did a global reset, charged me $240.00 and told me it was fixed. It shutdown 2 times before I got out of their parking lot.”
Owner complaint to NHTSAFiled Oct 17, 2026Electrical system, Unknown or otherODI 11771771
Data from NHTSA Complaints API (owner reports, unverified) · synced Nov 3, 2026
04 —Key specs

Engines, transmissions & drive

12 versions rated by the EPA
EPA class
Standard Pickup Trucks 2WD, Standard Pickup Trucks 4WD
Engines
3.0L 6-cyl turbo diesel · 2.7L 4-cyl turbo · 5.3L 8-cyl · 4.3L 6-cyl · 6.2L 8-cyl
Transmissions
Automatic 10-spd · Automatic 8-spd · Automatic 6-spd
Drive
Rear-Wheel Drive · 4-Wheel Drive
Fuel
Diesel · Regular Gasoline · Premium Gasoline

Towing, payload and dimensions aren’t in the EPA or NHTSA data, so we don’t list them.

Data from EPA fueleconomy.gov · synced Nov 3, 2026EPA listing
05 —Fuel economy

EPA fuel economy by version

City / highway / combined, annual fuel cost and CO₂
EPA
VersionCityHwyComb.Fuel / yrCO₂ g/mi
Sierra 2WD
Auto 10-spd, 6 cyl, 3.0 L, Diesel, Turbo · Rear-Wheel Drive
233026$3,600392
Sierra 4WD
Auto 10-spd, 6 cyl, 3.0 L, Diesel, Turbo · 4-Wheel Drive
222624$3,900430
Sierra 2WD
Auto 8-spd, 4 cyl, 2.7 L, Turbo, SIDI; 4-mode/Sport transmission · Rear-Wheel Drive
202321$3,050421
Sierra 2WD
Auto 8-spd, 4 cyl, 2.7 L, Turbo, SIDI; 3-mode transmission (work truck) · Rear-Wheel Drive
202321$3,050422
Sierra 2WD
Auto 8-spd, 8 cyl, 5.3 L, SIDI; with Cylinder Deactivation · Rear-Wheel Drive
172319$3,400466
Sierra 4WD
Auto 10-spd, 8 cyl, 5.3 L, SIDI; Stop-Start · 4-Wheel Drive
162219$3,400479
Sierra 2WD
Auto 6-spd, 8 cyl, 5.3 L, SIDI; Active Fuel Management · Rear-Wheel Drive
152117$3,800523
Sierra 2WD
Auto 6-spd, 6 cyl, 4.3 L, SIDI · Rear-Wheel Drive
162117$3,800523
Sierra 2WD
Auto 8-spd, 8 cyl, 5.3 L, SIDI · Rear-Wheel Drive
152217$3,800515
Sierra 4WD
Auto 10-spd, 8 cyl, 6.2 L, SIDI; Stop-Start · 4-Wheel Drive
162017$4,700510
Sierra 2WD
Auto 6-spd, 8 cyl, 5.3 L, SIDI; FFV · Rear-Wheel Drive
151916$4,000547
Sierra 2WD
Auto 6-spd, 8 cyl, 5.3 L, SIDI · Rear-Wheel Drive
142116$4,000541
  • Sierra 2WD
    Auto 10-spd, 6 cyl, 3.0 L, Diesel, Turbo
    23 city · 30 hwy · $3,600/yr
    26
    mpg comb.
  • Sierra 4WD
    Auto 10-spd, 6 cyl, 3.0 L, Diesel, Turbo
    22 city · 26 hwy · $3,900/yr
    24
    mpg comb.
  • Sierra 2WD
    Auto 8-spd, 4 cyl, 2.7 L, Turbo, SIDI; 4-mode/Sport transmission
    20 city · 23 hwy · $3,050/yr
    21
    mpg comb.
  • Sierra 2WD
    Auto 8-spd, 4 cyl, 2.7 L, Turbo, SIDI; 3-mode transmission (work truck)
    20 city · 23 hwy · $3,050/yr
    21
    mpg comb.
  • Sierra 2WD
    Auto 8-spd, 8 cyl, 5.3 L, SIDI; with Cylinder Deactivation
    17 city · 23 hwy · $3,400/yr
    19
    mpg comb.
  • Sierra 4WD
    Auto 10-spd, 8 cyl, 5.3 L, SIDI; Stop-Start
    16 city · 22 hwy · $3,400/yr
    19
    mpg comb.
  • Sierra 2WD
    Auto 6-spd, 8 cyl, 5.3 L, SIDI; Active Fuel Management
    15 city · 21 hwy · $3,800/yr
    17
    mpg comb.
  • Sierra 2WD
    Auto 6-spd, 6 cyl, 4.3 L, SIDI
    16 city · 21 hwy · $3,800/yr
    17
    mpg comb.
  • Sierra 2WD
    Auto 8-spd, 8 cyl, 5.3 L, SIDI
    15 city · 22 hwy · $3,800/yr
    17
    mpg comb.
  • Sierra 4WD
    Auto 10-spd, 8 cyl, 6.2 L, SIDI; Stop-Start
    16 city · 20 hwy · $4,700/yr
    17
    mpg comb.
  • Sierra 2WD
    Auto 6-spd, 8 cyl, 5.3 L, SIDI; FFV
    15 city · 19 hwy · $4,000/yr
    16
    mpg comb.
  • Sierra 2WD
    Auto 6-spd, 8 cyl, 5.3 L, SIDI
    14 city · 21 hwy · $4,000/yr
    16
    mpg comb.
Data from EPA fueleconomy.gov · synced Nov 3, 2026 · Fuel cost is EPA’s annual estimate (15,000 mi, 55% city)
06 —Safety

NHTSA 5-Star Safety Ratings

6 tested variants
Overall rating
4/ 5
4 of 5
GMC Sierra 1500 PU/CC 4WD
Frontal crash
4 of 5
Side crash
5 of 5
Side pole
5 of 5
Rollover
4 of 5
Rollover risk
19.8%
Overall
5 / 5
GMC Sierra 1500 PU/EC 4WD
Frontal crash
4 of 5
Side crash
5 of 5
Side pole
5 of 5
Rollover
4 of 5
Rollover risk
19.8%
Overall
5 / 5
GMC Sierra 1500 PU/RC 4WD
Frontal crash
4 of 5
Side crash
5 of 5
Side pole
5 of 5
Rollover
4 of 5
Rollover risk
19.8%
Overall
4 / 5
GMC Sierra 1500 PU/CC 2WD
Frontal crash
4 of 5
Side crash
5 of 5
Side pole
5 of 5
Rollover
4 of 5
Rollover risk
19.1%
Data from NHTSA NCAP Safety Ratings API · synced Nov 3, 2026Vehicle 15364Vehicle 15362Vehicle 15360
07 —Maintenance

Maintenance basics

General guidance, not the OEM schedule. Check your owner’s manual.
General guidance
ItemMilesTimeNote
Engine oil & filter5,000–10,000 mi6–12 monthsFollow the oil-life monitor if fitted
Tire rotation5,000–7,500 miEvery oil changeCheck pressure monthly
Engine air filter15,000–30,000 mi1–2 yearsSooner in dusty areas
Cabin air filter15,000–25,000 mi1–2 years
Brake fluid—2–3 yearsAbsorbs moisture over time
Coolant60,000–100,000 mi5–10 yearsLong-life coolants last longer
Spark plugs60,000–100,000 mi—Iridium/platinum plugs at the long end
12V battery—3–5 yearsHeat shortens battery life
  • Engine oil & filter5,000–10,000 mi
    6–12 months
  • Tire rotation5,000–7,500 mi
    Every oil change
  • Engine air filter15,000–30,000 mi
    1–2 years
  • Cabin air filter15,000–25,000 mi
    1–2 years
  • Brake fluid—
    2–3 years
  • Coolant60,000–100,000 mi
    5–10 years
  • Spark plugs60,000–100,000 mi
    —
  • 12V battery—
    3–5 years
Typical intervals for modern cars. Severe service (towing, short trips, extreme heat or cold) shortens them.
09 —FAQ

2021 Sierra questions

How many recalls does the 2021 GMC Sierra have?

7 safety recalls as of Nov 3, 2026, according to NHTSA. Recall repairs are free at a dealer. Check your VIN to see whether your car is included and whether the repair was done.

What are the most common 2021 GMC Sierra problems?

Owners filed 599 complaints with NHTSA. The most-cited components are engine (323), power train (145), electrical system (76). Complaints are unverified owner reports and aren't adjusted for how many cars were sold.

What MPG does the 2021 GMC Sierra get?

The EPA rates the 2021 GMC Sierra at 16–26 mpg combined, depending on engine and drivetrain (12 versions rated).

How safe is the 2021 GMC Sierra?

NHTSA's New Car Assessment Program gives the 2021 GMC Sierra 4–5 out of 5 stars overall.

Data from NHTSA & EPA · synced Nov 3, 2026