Owner complaints, recalls, fuel economy and safety ratings from public NHTSA and EPA data, updated Oct 17, 2026.
The 2021 GMC Sierra has 587 owner complaints filed with NHTSA, the most for the engine at 316. Combined fuel economy ranges from 14 to 26 mpg, with a 5-year fuel cost of $15,470 to $25,150 at U.S. average prices. NHTSA lists an overall rating of 4 stars. There are 7 recall campaigns that may apply, covering transmission and drivetrain, engine cooling, tires, and others.
Written by AI from public EPA and NHTSA data. Not a review.
Fuel economy
14–26 mpgcombined; city 13–23, highway 16–30; every version of this model year
Five years of fuel
$15,470–$25,150U.S. average; Ohio $13,820–$23,700 at local prices; every version of this model year; fuel only, not other costs of owning it; 15,000 miles a year, at EIA fuel prices for the week of Oct 12, 2026
NHTSA's VIN data lists these trims for the 2021 Sierra. A trim's engine and numbers are shown as its own only where EPA names versions after the trim and no other version could be it; "seen with" means a source shows that engine on the trim, not that it was the only one. Recalls and complaints cover the whole model year: whether a recall applies to a car depends on its VIN, on NHTSA's recall lookup.
Owners have filed 587 complaints with NHTSA about the 2021 Sierra. These are unverified owner reports, counted by the part of the car they name; one complaint can name several parts. Counts aren't adjusted for how many were sold, so they don't show how reliable a car is.
Complaints by part of the car
Part
Complaints
Crashes
Fires
Injuries
Engine
316
0
5
1
Power train
142
0
0
0
Electrical system
75
0
3
1
Engine and engine cooling
49
0
0
0
Unknown or other
43
1
1
0
Fuel/propulsion system
39
0
1
0
Steering
34
2
0
0
Service brakes
23
1
1
0
Structure
13
1
0
0
Latches/locks/linkages
10
0
0
0
Suspension
10
1
0
0
Lane departure
8
0
0
0
13 more parts
Vehicle speed control
7
0
0
0
Visibility/wiper
7
0
0
0
Air bags
6
2
1
1
Forward collision avoidance
6
0
0
0
Wheels
5
2
0
0
Back over prevention
4
0
0
0
Tires
4
0
0
0
Seat belts
3
0
0
0
Exterior lighting
2
0
0
0
Fuel system, diesel
1
0
0
0
Fuel system, gasoline
1
0
0
0
Seats
1
0
0
1
Service brakes, hydraulic
1
0
0
0
Complaints by model year
Newer years have had less time to collect complaints, and counts aren't adjusted for sales, so a shorter bar doesn't mean a more reliable year.
NHTSA lists 7 recall campaigns for the 2021 Sierra over its history. Campaigns are matched by model and year, so each one may apply to a given car, and its repair may already be done: check a VIN on NHTSA's recall lookup for the open recalls on that exact car.
Power train: automatic transmission; Power train: automatic transmission
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.
Risk: Rear wheel lock up increases the risk of a crash.
Remedy: Dealers will inspect the vehicles and update the transmission control software, free of charge. Owner notification letters were mailed March 6, 2026. Owners may contact GMC customer service at 1-800-462-8782 or Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N252516560. Vehicle Identification Numbers (VINs) involved in this recall became searchable on NHTSA.gov on February 12, 2026.
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.
Risk: Engine failure increases the risk of a crash.
Remedy: Dealers will inspect the engine, and as necessary, repair or replace the engine. For vehicles that pass inspection, dealers will add higher viscosity oil, install 6 oil fill cap, replace the oil filter, and update the owner's manual. Repairs will be performed free of charge. Owner notification letters were mailed June 18, 2025. Owners may contact Cadillac customer service at 1-800-333-4223, Chevrolet customer service at 1-800-222-1020, or GMC customer service at 1-800-462-8782. GM's number for this recall is N252494000.
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.
Risk: Rear wheel lock-up can increase the risk of a crash.
Remedy: Dealers will install new transmission control module software, free of charge. GM will provide a special coverage program to cover the repair of transmissions that are identified by the remedy software as containing a defective control valve. Owner notification letters were mailed December 12, 2024. Owners may contact GM customer service at 1-888-988-7267, Cadillac customer service at 1-800-458-8006, GMC customer service at GMC 1-800-462-8782 or Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N242454440.
General Motors (GM) is recalling certain 2019-2021 GMC Sierra 1500 and Silverado 1500 vehicles equipped with certain accessory road tires and a 17" spare tire. The 17" spare tire provided with the vehicle is not compatible for use with the accessory wheels, which can cause the anti-lock brake system (ABS) to not function properly under certain conditions.
Risk: An ABS system that does not function properly can increase the risk of a crash.
Remedy: Dealers will provide a new 17" spare tire and wheel assembly that is compatible with the accessory wheels, free of charge. Dealers will also apply a new spare tire information label, and provide owners with an owner's manual insert clarifying which spare tire to use with the accessory road tires and with the 17" original tires. Owner notification letters were mailed February 7, 2022. Owners may contact GM customer service at 1-800-462-8782 or GMC customer service at 1-800-462-8782. GM's number for this recall is N212346510.
General Motors, LLC (GM) is recalling certain 2020 Chevrolet Bolt EV and 2021 GMC Canyon and Sierra 1500, 2500 and 3500, Yukon, Yukon XL, Cadillac Escalade and Escalade ESV and Chevrolet Blazer, Camaro, Colorado, Equinox, Silverado 1500, 2500 and 3500, Suburban and Tahoe vehicles. Incorrect bolts may have been used at one or more fastening locations to secure the seat belts to the vehicle. If an incorrect bolt was used, the seat belt may not be properly attached to the vehicle.
Risk: If a seat belt assembly is not properly attached to the vehicle, the seat belt may not properly restrain an occupant in the event of a crash, increasing the risk of injury.
Remedy: GM will notify owners, and dealers will replace the suspect bolts, free of charge. The recall began January 29, 2021. Owners may contact GMC customer service at 1-800-462-8785, Cadillac customer service at 1-800-458-8006, or Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N202322230.
General Motors, LLC (GM) is recalling certain 2019-2021 Chevrolet Silverado 1500 and GMC Sierra 1500, 2021 Chevrolet Suburban and Tahoe and GMC Yukon XL and 2020-2021 Chevrolet Silverado 2500 and 3500 and GMC Sierra 2500 and 3500 vehicles. The seat belt brackets may not be secured to the seat frame in the front-row center seating position.
Risk: If a seat-belt bracket is not secured, the seat belt may not properly restrain an occupant in the front-row center seat position, increasing the risk of injury in a crash.
Remedy: GM will notify owners, and dealers will inspect left-side and right-side front-row center seat-belt bracket attachments and reassemble it correctly as necessary, free of charge. The recall began January 26, 2021. Owners may contact GMC customer service at 1-800-462-8782, Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N202314670.
General Motors LLC (GM) is recalling certain 2020 Buick Enclave, Cadillac XT5, GMC Acadia and Chevrolet Traverse vehicles and 2020-2021 Chevrolet Silverado 1500, GMC Sierra 1500 vehicles. The vehicles may have been manufactured with Continental tires that were overcured.
Risk: Overcured tires may experience a carcass break in the sidewall resulting in a sudden air loss or could develop a belt edge separation which could lead to partial or full tread/belt loss. Either condition increases the risk of a crash.
Remedy: GM will notify owners, and dealers will inspect vehicles and replace tires that have DOT number and production mold number combinations identified by Continental, free of charge. The recall began December 17, 2020. Owners may contact GMC customer service at 1-888-988-7267, Buick customer service at 1-866-608-8080, Chevrolet customer service at 1-800-222-1020 or Cadillac customer service at 1-800-458-8006. GM's number for this recall is N202319030.
Carmakers sent NHTSA 1,454 service bulletins and notices that cover the 2021 Sierra, the latest on Oct 5, 2026. They tell dealers how to fix known issues.
The parts they mention most: equipment (322), electrical system (318), engine and engine cooling (287), unknown or other (197), power train (183).
NHTSA defect investigations
Opening an investigation isn't a finding of a defect. Outcomes are as NHTSA's summary states them. A recall is shown as an investigation's outcome only where NHTSA's summary names it; other recalls NHTSA's file lists with it are marked as listed, not caused.
Investigation
Part
Opened
Status
Engineering analysis EA26005 Loss of motive power due to engine failure post recall remedy · covers 3 makes
The owner's manual gives the oil and how often to change it. We show oil facts only once we've checked them against the manual, and we haven't yet for the 2021 Sierra.
These are searches on those sites; we don't copy or check their listings. Your ZIP is used for these links and never kept.
Specs
EPA class: standard pickup trucks. EPA greenhouse gas score: 1–5 out of 10. Each version EPA tested:
Swipe the table sideways for more columns.
Version
Engine
Transmission
Fuel
City / hwy / comb
Sierra Rear-Wheel Drive
3.0 L, 6 cyl, turbo
Automatic 10-spd
Diesel
23 / 30 / 26
Sierra 4-Wheel Drive
3.0 L, 6 cyl, turbo
Automatic 10-spd
Diesel
22 / 26 / 24
Sierra Rear-Wheel Drive
2.7 L, 4 cyl, turbo
Automatic 8-spd
Regular Gasoline
20 / 23 / 21
Sierra Rear-Wheel Drive
5.3 L, 8 cyl
Automatic 8-spd
Regular Gasoline
17 / 23 / 19
Sierra 4-Wheel Drive
5.3 L, 8 cyl
Automatic 10-spd
Regular Gasoline
16 / 22 / 19
Sierra 4-Wheel Drive
2.7 L, 4 cyl, turbo
Automatic 8-spd
Regular Gasoline
18 / 21 / 19
Sierra 4-Wheel Drive
5.3 L, 8 cyl
Automatic 8-spd
Regular Gasoline
16 / 21 / 18
Sierra 4-Wheel Drive
5.3 L, 8 cyl
Automatic 10-spd
Regular Gasoline
15 / 21 / 18
Sierra Rear-Wheel Drive
5.3 L, 8 cyl
Automatic 6-spd
Regular Gasoline
15 / 21 / 17
Sierra 4-Wheel Drive
6.2 L, 8 cyl
Automatic 10-spd
Premium Gasoline
16 / 20 / 17
Sierra 4-Wheel Drive
5.3 L, 8 cyl
Automatic 6-spd
Regular Gasoline
15 / 20 / 17
Sierra 4-Wheel Drive
4.3 L, 6 cyl
Automatic 6-spd
Regular Gasoline
15 / 20 / 17
Sierra Rear-Wheel Drive
4.3 L, 6 cyl
Automatic 6-spd
Regular Gasoline
16 / 21 / 17
Sierra Rear-Wheel Drive
5.3 L, 8 cyl
Automatic 8-spd
Regular Gasoline
15 / 22 / 17
Sierra Rear-Wheel Drive
5.3 L, 8 cyl
Automatic 6-spd
Regular Gasoline or E85
15 / 19 / 16
Sierra 4-Wheel Drive
5.3 L, 8 cyl
Automatic 6-spd
Regular Gasoline or E85
14 / 18 / 16
Sierra Rear-Wheel Drive
5.3 L, 8 cyl
Automatic 6-spd
Regular Gasoline
14 / 21 / 16
Sierra 4-Wheel Drive
5.3 L, 8 cyl
Automatic 6-spd
Regular Gasoline
14 / 20 / 16
Sierra 4-Wheel Drive
5.3 L, 8 cyl
Automatic 8-spd
Regular Gasoline
14 / 20 / 16
Sierra 4-Wheel Drive
6.2 L, 8 cyl
Automatic 10-spd
Premium Gasoline
15 / 20 / 16
Sierra 4-Wheel Drive
5.3 L, 8 cyl
Automatic 6-spd
Regular Gasoline
14 / 17 / 15
Sierra 4-Wheel Drive
4.3 L, 6 cyl
Automatic 6-spd
Regular Gasoline
14 / 16 / 15
Sierra Rear-Wheel Drive
5.3 L, 8 cyl
Automatic 6-spd
Regular Gasoline
14 / 18 / 15
Sierra 4-Wheel Drive
5.3 L, 8 cyl
Automatic 6-spd
Regular Gasoline
13 / 17 / 14
Sierra Rear-Wheel Drive
5.3 L, 8 cyl
Automatic 6-spd
Regular Gasoline
13 / 18 / 14
Sierra AT4 4-Wheel Drive
3.0 L, 6 cyl, turbo
Automatic 10-spd
Diesel
22 / 26 / 24
Sierra AT4 4-Wheel Drive
5.3 L, 8 cyl
Automatic 10-spd
Regular Gasoline
16 / 21 / 18
Sierra AT4 4-Wheel Drive
5.3 L, 8 cyl
Automatic 8-spd
Regular Gasoline
16 / 21 / 18
Sierra AT4 4-Wheel Drive
6.2 L, 8 cyl
Automatic 10-spd
Premium Gasoline
15 / 19 / 17
Sierra AT4 4-Wheel Drive
5.3 L, 8 cyl
Automatic 10-spd
Regular Gasoline
15 / 21 / 17
Sierra AT4 4-Wheel Drive
5.3 L, 8 cyl
Automatic 6-spd
Regular Gasoline
14 / 18 / 16
Sierra AT4 4-Wheel Drive
5.3 L, 8 cyl
Automatic 8-spd
Regular Gasoline
14 / 20 / 16
Sierra AT4 4-Wheel Drive
6.2 L, 8 cyl
Automatic 10-spd
Premium Gasoline
14 / 19 / 16
Sources and dates
U.S. EPA fuel economy data, file of Sep 29, 2026
NHTSA owner complaints, file of Oct 17, 2026
NHTSA recalls, file of Oct 17, 2026
NHTSA manufacturer communications, file of Oct 17, 2026
NHTSA defect investigations, file of Oct 17, 2026
NHTSA 5-Star Safety Ratings, file of Aug 7, 2026
U.S. Energy Information Administration, file of Oct 12, 2026
Fuel cost: EPA mpg with fuel prices for the week of Oct 12, 2026 and electricity prices for Jul 2026. Source: U.S. Energy Information Administration (Oct 2026). Complaints are unverified reports owners filed with NHTSA. About the data