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NHTSA Federal Consumer Defect Registry

2021 GMC Sierra 1500 Owner Complaints (534)

Analysis of 534 verified consumer complaints submitted to the National Highway Traffic Safety Administration (NHTSA). Filtered and clustered by vehicle subsystem to identify genuine recurring mechanical and electrical flaws.

Total Complaints
534
Defect Clusters
7 Categories
Avg Failure Range
24k mi
Est. Repair Cost
$950 – $3,200
Defects & ProblemsSafety Recalls7Owner Complaints534
Switch Sierra 1500 Model Year Complaints
202595 reports2024329 reports2023435 reports2022547 reports2021534 reports2020444 reports2019623 reports2018296 reports2017426 reports201647 reports2015812 reports2014858 reports
NHTSA Defect Subsystem Breakdown

2021 Sierra 1500 Failure Distribution by Vehicle Subsystem

100% Normalized Telemetry
38%26%16%12%
Engine & Powertrain:38%
Electrical & Sensors:26%
Steering & Suspension:16%
Brakes & ABS Hydraulics:12%
Airbags & Body Structure:8%
Clustered Telemetry

Top Defect Complaint Groups (7)

Ranked by NHTSA Frequency
ENGINE & COOLING365 Verified Complaints

Engine Stalling, Oil Consumption & Cooling Defect Reports

Critical Severity

Reported Symptoms: Engine sudden stall / hesitation while driving, Abnormal oil burning / consumption, Check Engine Light (MIL) flashing, Engine overheating / coolant loss

Median Failure Mileage24,000 milesIQR: 8,116 – 63,500 mi
Estimated Repair Cost$950 – $3,200 (Source: MazicBay Repair Intelligence Model)
Associated Fault Codes
TRANSMISSION & DRIVETRAIN173 Verified Complaints

Transmission Hesitation, Hard Shifting & Slipping Reports

High Severity

Reported Symptoms: Hard gear shifts / delayed engagement into Drive/Reverse, Transmission shudder / jerking under acceleration, Transmission slipping between gears

Median Failure Mileage60,039 milesIQR: 38,250 – 81,000 mi
Estimated Repair Cost$1,400 – $3,800 (Source: MazicBay Repair Intelligence Model)
Associated Fault Codes
ELECTRICAL SYSTEM & BATTERY92 Verified Complaints

Electrical Parasitic Drain, Infotainment & Harness Reports

Critical Severity

Reported Symptoms: Unexplained battery drain after sitting overnight, Infotainment display / instrument cluster blackouts, Accessory malfunction / alternator fault warnings

Median Failure Mileage36,000 milesIQR: 11,800 – 60,077 mi
Estimated Repair Cost$280 – $850 (Source: MazicBay Repair Intelligence Model)
Associated Fault Codes
BRAKING SYSTEM & ABS56 Verified Complaints

Service Brakes, ABS Actuator & Master Cylinder Reports

Critical Severity

Reported Symptoms: Spongy or hard brake pedal travel, ABS / Brake warning light illuminated, Extended stopping distance / pedal vibration

Median Failure Mileage29,000 milesIQR: 22,500 – 62,000 mi
Estimated Repair Cost$350 – $1,100 (Source: MazicBay Repair Intelligence Model)
Associated Fault Codes
STEERING & SUSPENSION51 Verified Complaints

Electric Power Steering Assist & Suspension Noise Reports

Critical Severity

Reported Symptoms: Sudden loss of electric power steering assist, Steering wheel pull or highway wander, Clunking / knocking noise over bumps

Median Failure Mileage13,184 milesIQR: 8,592 – 26,092 mi
Estimated Repair Cost$450 – $1,400 (Source: MazicBay Repair Intelligence Model)
Associated Fault Codes
FUEL SYSTEM & INJECTION14 Verified Complaints

Fuel Pump Pressure Loss & Fuel Delivery Defect Reports

Medium Severity

Reported Symptoms: Sudden loss of propulsion power at highway speeds, Extended engine cranking / failure to restart, Fuel odor near fuel tank / engine bay

Median Failure Mileage55,000 milesIQR: 35,000 – 75,000 mi
Estimated Repair Cost$650 – $1,250 (Source: MazicBay Repair Intelligence Model)
Associated Fault Codes
AIRBAGS & SAFETY RESTRAINTS10 Verified Complaints

Airbag Occupant Detection & Inflator Defect Reports

Critical Severity

Reported Symptoms: SRS Airbag warning lamp illuminated, Passenger occupant classification sensor failure, Seat belt retractor lockup

Median Failure Mileage3,800 milesIQR: 2,900 – 4,700 mi
Estimated Repair Cost$400 – $1,200 (Source: MazicBay Repair Intelligence Model)
Associated Fault Codes
Full Reliability Report2021 Sierra 1500 Common ProblemsFederal Safety Recalls2021 Sierra 1500 Recalls (7)All Generation YearsSierra 1500 Multi-Year Hub