2021 Gmc Sierra Safety Report

2021 GMC Sierra plagued by widespread engine and powertrain failures with no NHTSA safety ratings or recalls.

514Complaints
0Recalls
35/100Reliability Score
9Crash Reports
7Fire Reports
3Injuries
Most reported components: Engine (147)Power Train (70)Engine And Engine Cooling (36)Electrical System (30)Power Train,Engine (27)Service Brakes (16)Unknown Or Other (14)Steering (12)Latches/Locks/Linkages (10)Unknown Or Other,Engine (10)

AI Safety Analysis for the 2021 Gmc Sierra

The 2021 GMC Sierra has a concerning safety profile, primarily due to a high volume of engine and powertrain-related complaints. With 514 total complaints, 9 crashes, 7 fires, and 3 injuries reported to NHTSA, the vehicle exhibits significant issues despite having no official safety ratings from NHTSA (Overall, Frontal, Side, Rollover are all N/A). The most prominent complaint category is 'ENGINE' with 147 reports, followed by 'POWER TRAIN' with 70, and 'ENGINE AND ENGINE COOLING' with 36. These categories collectively account for a substantial portion of the total complaints, indicating systemic problems. Common complaint patterns include sudden loss of acceleration, engine failure (including connecting rod failures and lifter failures), transmission shuddering, hard shifts, and complete transmission failures. Several complaints mention the vehicle entering 'limp mode' or completely shutting off while driving, posing a severe safety risk. There are also reports of defective DEF tanks and engine coolant control valves, which can lead to reduced power or engine damage. The absence of NHTSA crash test ratings makes it difficult to assess its performance in collision scenarios, but the high number of operational failures is a significant concern. Despite the numerous complaints detailing critical component failures, there are currently no recalls issued for the 2021 GMC Sierra. This lack of recall action, combined with the high frequency of severe engine and powertrain issues, suggests that owners may face significant repair costs and potential safety hazards. The reported incidents of engine failure, transmission issues, and sudden loss of power while driving highlight a critical need for manufacturer intervention to address these widespread problems.

Reliability Score

The 2021 Gmc Sierra receives a reliability score of 35 out of 100 based on analysis of NHTSA complaint data, recall history, crash reports, and safety ratings. This indicates below-average reliability. Significant issues have been reported by owners and should be carefully evaluated before purchase.

Known Issues for the 2021 Gmc Sierra

The following issues have been identified from NHTSA complaint data and owner reports for the 2021 Gmc Sierra:

IssueSeverityFrequencyTypical Mileage
Engine Failure (E.G., Connecting Rod, Lifter Failure)
Numerous reports of catastrophic engine failure, including thrown connecting rods, lifter failures, and complete engine shutdowns, often without prior warning. Some instances occurred shortly after recall tests or repairs.
High Common 5000-126000 miles
Transmission Shuddering And Hard Shifts
Drivers report violent jerking, shuddering, and hard shifts, particularly under light acceleration or when shifting gears. Some complaints mention rear wheels locking up or complete transmission failure requiring replacement.
High Common unknown miles
Sudden Loss Of Acceleration/Power
Vehicle suddenly loses ability to accelerate, feels like it shifts into neutral, or enters limp mode while driving at various speeds, including highway speeds. This can lead to the vehicle shutting off completely.
High Common unknown miles
Defective Def Tank/Engine Coolant Control Valve
Reports of defective DEF tanks and engine coolant control valves, particularly on 3.0L Diesel engines. These issues can lead to reduced power, engine damage, and are often on backorder, leaving owners without a vehicle.
Medium Occasional unknown miles
Tailgate Opening Unexpectedly
Rear tailgate opens or drops unexpectedly, especially when wet (heavy rain or after a car wash), with no warning other than a clicking sound.
Low Rare unknown miles

Common Problems Reported by Owners

Based on NHTSA complaint data, the following components account for the majority of reported issues with the 2021 Gmc Sierra:

Power Train 13% of complaints

70 complaints relate to the power train, encompassing transmission shuddering, hard shifts, and complete transmission failures, often leading to the vehicle being inoperable.

Engine And Engine Cooling 7% of complaints

36 complaints specifically mention engine and engine cooling issues, including defective engine coolant control valves and related problems leading to reduced power.

Electrical System 5% of complaints

30 complaints regarding the electrical system, including intermittent warning lights, infotainment system malfunctions (e.g., Android Auto disabling the system), and issues after engine repairs.

Service Brakes 3% of complaints

16 complaints related to service brakes, though specific patterns are less clear from the provided samples, some mention 'check brake system' warnings.

Frequently Asked Questions About the 2021 Gmc Sierra

Is the 2021 GMC Sierra safe?

Based on NHTSA data, the 2021 GMC Sierra has a concerning safety record due to 514 total complaints, including 9 crashes, 7 fires, and 3 injuries. A significant portion of these complaints points to critical engine and powertrain failures that can lead to sudden loss of power or vehicle shutdown while driving. The absence of official NHTSA crash test ratings makes a comprehensive safety assessment difficult, but the operational reliability issues are a major concern.

What are common problems with the 2021 GMC Sierra?

The most reported issues for the 2021 GMC Sierra are related to the ENGINE (147 complaints), POWER TRAIN (70 complaints), and ENGINE AND ENGINE COOLING (36 complaints). Common problems include catastrophic engine failures (e.g., connecting rod, lifter issues), transmission shuddering, hard shifts, sudden loss of acceleration, and defective DEF tanks or engine coolant control valves.

Are there any recalls for the 2021 GMC Sierra?

As of the provided data, there are no recalls issued for the 2021 GMC Sierra, despite a high volume of severe complaints regarding engine and powertrain failures.

How does the 2021 GMC Sierra perform in crash tests?

The 2021 GMC Sierra currently has no official NHTSA safety ratings for Overall, Frontal, Side, or Rollover crash tests. Therefore, its performance in crash scenarios cannot be assessed based on this data.

What should I do if my 2021 GMC Sierra experiences engine or transmission issues?

If your 2021 GMC Sierra experiences engine or transmission issues, especially sudden loss of power or unusual noises, it is critical to safely pull over and have the vehicle inspected by a qualified mechanic immediately. Given the numerous reports of catastrophic failures, do not ignore warning signs. Document all issues and repairs, and consider filing a complaint with NHTSA.

Buyer Advice

Our recommendation: Given the high volume of severe engine and powertrain complaints and the lack of NHTSA safety ratings or recalls, potential buyers should exercise extreme caution and thoroughly investigate the vehicle's service history, especially for engine and transmission repairs, before purchasing a 2021 GMC Sierra.

NHTSA Data Summary for 2021 Gmc Sierra

This safety report is based on a comprehensive analysis of data from the National Highway Traffic Safety Administration (NHTSA) for the 2021 Gmc Sierra. The data includes 514 consumer complaints filed by vehicle owners, 0 manufacturer-initiated safety recalls, 9 reported crashes, 7 fire incidents, 3 reported injuries, and safety rating assessments associated with this vehicle.

All data presented in this report is sourced from public NHTSA databases. Our AI analysis identifies patterns across complaint narratives, correlates them with recall history, and produces the safety assessment above. This analysis is updated as new complaints and recalls are filed with the NHTSA.

Consumers are encouraged to report vehicle safety problems to the NHTSA at nhtsa.gov. If your vehicle is subject to a recall, contact your dealer to schedule the free repair.