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2021 GMC Sierra 3500

Owner reports · Recalls · Investigations

Limited comparison data

There is not enough comparable history to draw a useful model-year comparison.

About this comparison →
20Owner complaints

Model-year median: 16

5Recall campaigns

View recall details →

1Investigations

View investigation details →

How this year compares

Owner complaints by model year

Other model years Selected year
14
201813
201951
202020
202131
202228
202344
2024
Compare all Sierra 3500 years →

Counts vary with age, sales and reporting. They are not failure rates.

What owners reported most

Power Train
7Service Brakes
5Electrical System
4Engine
3Unknown Or Other
3
All reported categories
Fuel/propulsion System
2Back Over Prevention
1Structure
1Tires
1Visibility
1

Tap a category to read its complaints. One report may name several components.

When problems were reported

Mileage at the reported incident

Limited mileage data: 4 of 20 reports include usable mileage. There isn’t enough coverage to show a useful chart.

NHTSA’s mileage field refers to the reported incident, not necessarily the filing date. This shows report counts, not the likelihood of a failure.

What to inspect

Issues worth paying extra attention to based on owner reports.

  • Power Train. Review the 7 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Service Brakes. Review the 5 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Electrical System. Review the 4 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →

NHTSA owner reports · September 18, 2026 snapshot.

0 crash reports0 fire reports0 injury reports

What owners actually said

20 reports
140,606 miles · Jun 12, 2026
Service Brakes

The contact filed the complaint on behalf of the owner of a 2021 GMC Sierra 3500. The contact stated that while the vehicle owner was driving at an undisclosed speed, the driver noticed that the rear wheels were attempting to lockup. The contact stated that the failure was noticeable while driving forward and while reversing. N…

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The contact filed the complaint on behalf of the owner of a 2021 GMC Sierra 3500. The contact stated that while the vehicle owner was driving at an undisclosed speed, the driver noticed that the rear wheels were attempting to lockup. The contact stated that the failure was noticeable while driving forward and while reversing. No warning light illuminated. The vehicle was taken to the independent mechanic, where it was diagnosed with detached rear brake pads and detached rear emergency brake shoes. In addition, the rear brake caliber had seized. The vehicle owner was informed that the rear brake pads and the rear emergency brake shoes needed to be replaced, and the rear brake caliber needed to be repaired. The vehicle was repaired. The dealer was made aware of the failure. The contact was advised to contact the NHTSA Hotline to report the failure. The manufacturer was not made aware of the failure. The failure mileage was approximately 140,606.

NHTSA ODI #11743698

Mileage unknown · Nov 24, 2025
Power Train

During takeoff the transmission acted as if it was in neutral while I was crossing traffic luckily, the semi truck that was coming towards me was able to stop. I had the vehicle towed to a shop. After the vehicle was towed to the shop the transmission acted normal when the mechanic searched the VIN number. There was a service b…

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During takeoff the transmission acted as if it was in neutral while I was crossing traffic luckily, the semi truck that was coming towards me was able to stop. I had the vehicle towed to a shop. After the vehicle was towed to the shop the transmission acted normal when the mechanic searched the VIN number. There was a service bulletin issued by General Motors for this exact problem. Had the semi not been able to stop. It could’ve very well killed me or my children. I suppose if it would’ve killed someone, maybe general motors would finally do a recall for this very disappointed in general motors and the NHTSA, the fact that this is an ongoing problem and has not been fixed and as a customer, I was not even notified that this problem existed is very alarming.

NHTSA ODI #11701315

26,000 miles · Sep 8, 2025
Electrical SystemVisibility

The contact owns a 2021 GMC Sierra 3500. The contact stated that while his wife had the vehicle idling with the rear defroster activated, shortly afterwards, she observed smoke coming from the plastic on the rear sliding window. After a visual inspection, the contact's wife observed that the plastic was melting, prompting her to…

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The contact owns a 2021 GMC Sierra 3500. The contact stated that while his wife had the vehicle idling with the rear defroster activated, shortly afterwards, she observed smoke coming from the plastic on the rear sliding window. After a visual inspection, the contact's wife observed that the plastic was melting, prompting her to deactivate the rear defroster. No warning lights were illuminated. The vehicle was taken to the dealer, who was unable to determine the cause of the failure. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was 26,000.

NHTSA ODI #11685740

70,000 miles · Aug 14, 2025
Back Over Prevention

The contact owns a 2021 GMC Sierra 3500. The contact stated that while reversing, the back over prevention camera screen displayed an image of the ground. The contact stated that the image was approximately ten feet behind the vehicle. The vehicle was taken to the dealer; however, the failure was not duplicated. The dealer repla…

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The contact owns a 2021 GMC Sierra 3500. The contact stated that while reversing, the back over prevention camera screen displayed an image of the ground. The contact stated that the image was approximately ten feet behind the vehicle. The vehicle was taken to the dealer; however, the failure was not duplicated. The dealer replaced the back over prevention camera system, however, the failure reoccurred. The contact stated that the original back over prevention camera was installed in another vehicle, and the back over prevention camera system worked as designed. The contact was informed that the back over prevention camera was not the cause of the failure. The manufacturer was made aware of the failure but provided no assistance. The failure mileage was approximately 70,000.

NHTSA ODI #11680762

Mileage unknown · May 12, 2025
Unknown Or Other

There is a known issue with these trucks with the infotainment screen blacking out, which renders the backup cameras inoperative. This is a huge safety risk and its astounding to me that this hasn't been recalled yet.

NHTSA ODI #11660333

Mileage unknown · Mar 8, 2025
Unknown Or Other

Vehicle is put into park after driving. Shift to Park warning comes on while vehicle is in park. Vehicle will not shut off due to this warning and must be left running unoccupied.

NHTSA ODI #11647125

Mileage unknown · Mar 8, 2025
Electrical System

When carrying the electronic key in my pocket the vehicle will lock/unlock presumably due to the remote contacting other items in the pocket. I have owned well over a dozen GM vehicles and never had this issue. I believe the remote design has the lock/unlock buttons too proud of the surrounding surface

NHTSA ODI #11647111

133,000 miles · Jan 27, 2025
Power Train

The contact's son owns a 2021 GMC Sierra 3500 Commercial Vehicle. The contact stated while her son was driving at an undisclosed speed uphill, the vehicle failed to shift to a gear higher than 5th gear. Additionally, the rear wheels locked up, causing the vehicle to come to a stop. The driver attempted to resume driving, but the…

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The contact's son owns a 2021 GMC Sierra 3500 Commercial Vehicle. The contact stated while her son was driving at an undisclosed speed uphill, the vehicle failed to shift to a gear higher than 5th gear. Additionally, the rear wheels locked up, causing the vehicle to come to a stop. The driver attempted to resume driving, but the vehicle failed to exceed 10 MPH. The contact was unsure whether a warning light had been illuminated. The vehicle was towed to the residence of the driver's girlfriend. The vehicle was then towed to the dealer, where it was diagnosed that the failure was related to NHTSA Campaign Number: 24V797000 (Power Train); however, the part to do the recall repair was not yet available. Additionally, the dealer informed the contact that the transmission needed to be replaced, but the part was not available. The vehicle was not repaired. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the failure and a case was filed. The failure mileage was approximately 133,000. Parts distribution disconnect.

NHTSA ODI #11638908

Mileage unknown · Jan 18, 2025
Power Train

Transmission had to be replaced from the dealership. Hard shifting dealership said truck was 23 days out of warranty. I couldn’t get into the dealership that truck was purchased from for 3 weeks. Had to go to the Jeff Gordon dealership, which is Chevrolet. And I had to replace the transmission.

NHTSA ODI #11636808

Mileage unknown · Nov 1, 2024
Electrical SystemEngineUnknown Or Other

Multiple instances of diesel engine emissions system parts and software failure. While driving, towing or not, the DIC would randomly display a message that the DEF level is low and reduced speed will occur in x-amount of miles and that mileage would then begin a visible countdown on the DIC, sometimes much more quickly than the…

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Multiple instances of diesel engine emissions system parts and software failure. While driving, towing or not, the DIC would randomly display a message that the DEF level is low and reduced speed will occur in x-amount of miles and that mileage would then begin a visible countdown on the DIC, sometimes much more quickly than the actual speed I was traveling. In other words, it might at first state 500 miles remaining, but then be counting down from 500 miles by one mile per second of time, or faster. Each instance, I would park and attempt to refill the DEF tank, only to discover that the tank is already full or near full. My truck’s DEF tank has now been replaced twice under warranty with the latest tank being installed at only 35,460 miles on the odometer. During the latest replacement, the technician also diagnosed and replaced the electrical wiring harness related to the DEF tank, stating that one of the connector pins was not reading the required voltage. There was also a faulty diesel particulate sensor that was replaced under warranty. This emissions system is problematic, and it is unsafe to due to the drive ability restrictions it imposes due to faulty software and equipment. I use my truck to tow, and it would make for a very unsafe condition to have my vehicle’s speed become limited as if the vehicle ran out of fuel. Mountain grades. Two-lane highways. Passing through bad neighborhoods. Driving in uninhabited areas, sometimes late at night. Family of 6 in the vehicle. Unacceptable. General Motors Corp. must create a permanent and fail-safe fix for this emissions system and implement the parts. The emissions system warranty should be extended from 80k miles to Lifetime to cover the vehicles affected.

NHTSA ODI #11623109

Official recalls

5

24V797000 · Power Train:automatic Transmission:control Module:software; Power Train:automatic Transmission:fluid/lubricant:valves/valve Body

Oct 24, 2024

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.

Consequence & remedy

Consequence: 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.

Additional source detail variants (2)

Power Train:automatic Transmission:fluid/lubricant:valves/valve Body

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.

Consequence: 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.

Power Train:automatic Transmission:control Module:software

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.

Consequence: 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.

24V060000 · Latches/locks/linkages:tailgate:latch

Feb 1, 2024

General Motors, LLC (GM) is recalling certain 2020-2024 Chevrolet Silverado 2500, 3500, GMC Sierra 2500 and 3500 vehicles equipped with power-unlatching tailgates. The tailgate's electronic gate-release switch may short circuit due to water intrusion, which can result in the tailgate inadvertently unlatching while the vehicle is in park.

Consequence & remedy

Consequence: An unlatched tailgate may open while driving and result in a loss of unsecured cargo, creating a road hazard and increasing the risk of a crash.

Remedy: Owners are advised to check that the tailgate is closed and latched before driving. Dealers will replace the exterior touchpad switch assemblies, free of charge. Owner notification letters were mailed May 17, 2024. Owners may contact Chevrolet customer service at 1-800-222-1020 or GMC customer service at 1-800-462-8782. GM's number for this recall is N232426400.

21V758000 · Service Brakes, Hydraulic:power Assist:electric:control Module

Sep 29, 2021

General Motors, LLC (GM) is recalling certain 2021-2022 Chevrolet Silverado 2500, Silverado 3500, GMC Sierra 2500, and Sierra 3500 vehicles with electronic brake control modules (EBCM) replaced during vehicle assembly. The bolts that attach the brake pressure modulator valve (BPMV) assembly may not be properly tightened, which could fail to seal the two sub-assemblies and allow water intrusion.

Consequence & remedy

Consequence: Water in the BPMV may cause an electrical short circuit and increase the risk of fire.

Remedy: Owners are advised to park outside and away from other structures until the recall repair is completed. Dealers will replace the BPMV assembly, free of charge. Owner notification letters were mailed on October 20, 2021. Owners may contact Chevrolet customer service at 1-800-222-1020 or GMC customer service at 1-800-462-8782. GM's number for this recall is N212349181.

20V811000 · Seat Belts; Seat Belts:critical Fasteners

Dec 23, 2020

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.

Consequence & remedy

Consequence: 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.

Additional source detail variants (2)

Seat Belts:critical Fasteners

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.

Consequence: 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.

Seat Belts

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.

Consequence: 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.

20V792000 · Seat Belts; Seat Belts:critical Fasteners

Dec 17, 2020

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.

Consequence & remedy

Consequence: 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.

Additional source detail variants (2)

Seat Belts:critical Fasteners

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.

Consequence: 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.

Seat Belts

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.

Consequence: 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.

Model-level recall history does not show whether a particular VIN is affected or has received a repair. Check a VIN with NHTSA ↗

NHTSA investigations

1

PE21010 · Air Bag Malfunction

Opened Apr 9, 2021 · Closed Aug 24, 2023

Status: closed (inferred from source dates) · Air Bags; Air Bags:frontal; Air Bags:frontal:driver Side:inflator Module; Air Bags:srs Malfunction Warning Lamp/light

On April 9, 2021, the Office of Defects Investigations (ODI) opened PE21-010 to investigate instances of air bag malfunction indicator light (MIL) illumination and potential for frontal air bag non-deployment in several vehicles manufactured by General Motors (GM). The vehicles included model year (MY) 2020 through 2021 CT4 and CT5 passenger cars, Sierra and Silverado trucks (1500/2500/3500 models), XT4 and MY 2021 Escalade, Suburban, Tahoe, Yukon SUVs.Technical Service Bulletin (TSB) 21-NA-005, issued in March 2021, addresses air bag MIL illumination with diagnostic trouble codes (DTCs) B0001-1B or B0012-0D. It cites rust particles in the connection terminal interface of the driver air bag inflator housing as the cause of the air bag MIL illumination. Illumination of the air bag MIL under these circumstances may result in a non-deployment of the frontal driver air bag during a frontal collision and increased risk of injury to the driver.GM stated a correlation exists between production delays due to the pandemic shutdown and premature corrosion initiation on the surface of the air bag inflator housing, which, in some cases, caused rust development during a seven (7) month period of vehicle production. In the rare instance when a rust particle dislodges from the driver air bag inflator housing and enters the air bag connector prior to assembly, an intermittent resistance spike at the air bag connector may result. The condition generates excessive resistance in the air bag electrical system when the steering wheel horn cover is manipulated or the steering wheel is turned. This excessive resistance is momentary. A crash commanding air bag deployment would need to occur exactly when the momentary excessive resistance occurs. Thus, there is a very low likelihood the hazard will present a risk during a crash of sufficient severity to warrant a commanded deployment. This failure mechanism occurs early in life and results in an air bag MIL illumination that corresponds to a DTC warning the driver that the vehicle requires service. The vehicle's air bag remains functional while the MIL is illuminated, and the DTC is present.Once the connection of the driver air bag module to the clockspring is made at the plant, or at the dealership for service, there is no longer an opportunity for rust migration into the connection point. The connector is sealed and has gold terminals, eliminating the expectation of fretting corrosion. All subject vehicles passed standard corrosion validation testing for extensive corrosion with no issue of air bag non-deployment.There is a low rate of occurrence: 1.41 incidents per thousand vehicles (IPTV) for all related occurrences, and 0.04 IPTV for occurrences with a mention of visible rust and/or corrosion on the air bag inflator housing. The average occurrence mileage for the subject vehicles is approximately 2,100. Every occurrence related to the alleged defect experienced an air bag MIL illumination and there are no verified allegations of air bag non-deployment within all data sources.To date, there have been no reported fires, crashes, injuries, or fatalities related to this issue. In view of the low rate, and the nature of early-life failure, the high detectability of failures, and low potential hazard to drivers, this Preliminary Evaluation (PE) is closed. The closing of this investigation does not constitute a finding by NHTSA that a safety-related defect does not exist. The agency reserves the right to take additional action if warranted by new circumstances.Review the ODI reports cited above at nhtsa.gov under the following identification numbers: 11537927, 11528888, 11525020, 11521401, 11506057, 11493107, 11486767, 11441525, 11433146, 11425658, 11423440, 11385267, 11376429, 11373466, 11366995.

Additional source detail variants (4)

Air Bags:frontal:driver Side:inflator Module

On April 9, 2021, the Office of Defects Investigations (ODI) opened PE21-010 to investigate instances of air bag malfunction indicator light (MIL) illumination and potential for frontal air bag non-deployment in several vehicles manufactured by General Motors (GM). The vehicles included model year (MY) 2020 through 2021 CT4 and CT5 passenger cars, Sierra and Silverado trucks (1500/2500/3500 models), XT4 and MY 2021 Escalade, Suburban, Tahoe, Yukon SUVs.Technical Service Bulletin (TSB) 21-NA-005, issued in March 2021, addresses air bag MIL illumination with diagnostic trouble codes (DTCs) B0001-1B or B0012-0D. It cites rust particles in the connection terminal interface of the driver air bag inflator housing as the cause of the air bag MIL illumination. Illumination of the air bag MIL under these circumstances may result in a non-deployment of the frontal driver air bag during a frontal collision and increased risk of injury to the driver.GM stated a correlation exists between production delays due to the pandemic shutdown and premature corrosion initiation on the surface of the air bag inflator housing, which, in some cases, caused rust development during a seven (7) month period of vehicle production. In the rare instance when a rust particle dislodges from the driver air bag inflator housing and enters the air bag connector prior to assembly, an intermittent resistance spike at the air bag connector may result. The condition generates excessive resistance in the air bag electrical system when the steering wheel horn cover is manipulated or the steering wheel is turned. This excessive resistance is momentary. A crash commanding air bag deployment would need to occur exactly when the momentary excessive resistance occurs. Thus, there is a very low likelihood the hazard will present a risk during a crash of sufficient severity to warrant a commanded deployment. This failure mechanism occurs early in life and results in an air bag MIL illumination that corresponds to a DTC warning the driver that the vehicle requires service. The vehicle's air bag remains functional while the MIL is illuminated, and the DTC is present.Once the connection of the driver air bag module to the clockspring is made at the plant, or at the dealership for service, there is no longer an opportunity for rust migration into the connection point. The connector is sealed and has gold terminals, eliminating the expectation of fretting corrosion. All subject vehicles passed standard corrosion validation testing for extensive corrosion with no issue of air bag non-deployment.There is a low rate of occurrence: 1.41 incidents per thousand vehicles (IPTV) for all related occurrences, and 0.04 IPTV for occurrences with a mention of visible rust and/or corrosion on the air bag inflator housing. The average occurrence mileage for the subject vehicles is approximately 2,100. Every occurrence related to the alleged defect experienced an air bag MIL illumination and there are no verified allegations of air bag non-deployment within all data sources.To date, there have been no reported fires, crashes, injuries, or fatalities related to this issue. In view of the low rate, and the nature of early-life failure, the high detectability of failures, and low potential hazard to drivers, this Preliminary Evaluation (PE) is closed. The closing of this investigation does not constitute a finding by NHTSA that a safety-related defect does not exist. The agency reserves the right to take additional action if warranted by new circumstances.Review the ODI reports cited above at nhtsa.gov under the following identification numbers: 11537927, 11528888, 11525020, 11521401, 11506057, 11493107, 11486767, 11441525, 11433146, 11425658, 11423440, 11385267, 11376429, 11373466, 11366995.

Air Bags:frontal

On April 9, 2021, the Office of Defects Investigations (ODI) opened PE21-010 to investigate instances of air bag malfunction indicator light (MIL) illumination and potential for frontal air bag non-deployment in several vehicles manufactured by General Motors (GM). The vehicles included model year (MY) 2020 through 2021 CT4 and CT5 passenger cars, Sierra and Silverado trucks (1500/2500/3500 models), XT4 and MY 2021 Escalade, Suburban, Tahoe, Yukon SUVs.Technical Service Bulletin (TSB) 21-NA-005, issued in March 2021, addresses air bag MIL illumination with diagnostic trouble codes (DTCs) B0001-1B or B0012-0D. It cites rust particles in the connection terminal interface of the driver air bag inflator housing as the cause of the air bag MIL illumination. Illumination of the air bag MIL under these circumstances may result in a non-deployment of the frontal driver air bag during a frontal collision and increased risk of injury to the driver.GM stated a correlation exists between production delays due to the pandemic shutdown and premature corrosion initiation on the surface of the air bag inflator housing, which, in some cases, caused rust development during a seven (7) month period of vehicle production. In the rare instance when a rust particle dislodges from the driver air bag inflator housing and enters the air bag connector prior to assembly, an intermittent resistance spike at the air bag connector may result. The condition generates excessive resistance in the air bag electrical system when the steering wheel horn cover is manipulated or the steering wheel is turned. This excessive resistance is momentary. A crash commanding air bag deployment would need to occur exactly when the momentary excessive resistance occurs. Thus, there is a very low likelihood the hazard will present a risk during a crash of sufficient severity to warrant a commanded deployment. This failure mechanism occurs early in life and results in an air bag MIL illumination that corresponds to a DTC warning the driver that the vehicle requires service. The vehicle's air bag remains functional while the MIL is illuminated, and the DTC is present.Once the connection of the driver air bag module to the clockspring is made at the plant, or at the dealership for service, there is no longer an opportunity for rust migration into the connection point. The connector is sealed and has gold terminals, eliminating the expectation of fretting corrosion. All subject vehicles passed standard corrosion validation testing for extensive corrosion with no issue of air bag non-deployment.There is a low rate of occurrence: 1.41 incidents per thousand vehicles (IPTV) for all related occurrences, and 0.04 IPTV for occurrences with a mention of visible rust and/or corrosion on the air bag inflator housing. The average occurrence mileage for the subject vehicles is approximately 2,100. Every occurrence related to the alleged defect experienced an air bag MIL illumination and there are no verified allegations of air bag non-deployment within all data sources.To date, there have been no reported fires, crashes, injuries, or fatalities related to this issue. In view of the low rate, and the nature of early-life failure, the high detectability of failures, and low potential hazard to drivers, this Preliminary Evaluation (PE) is closed. The closing of this investigation does not constitute a finding by NHTSA that a safety-related defect does not exist. The agency reserves the right to take additional action if warranted by new circumstances.Review the ODI reports cited above at nhtsa.gov under the following identification numbers: 11537927, 11528888, 11525020, 11521401, 11506057, 11493107, 11486767, 11441525, 11433146, 11425658, 11423440, 11385267, 11376429, 11373466, 11366995.

Air Bags

On April 9, 2021, the Office of Defects Investigations (ODI) opened PE21-010 to investigate instances of air bag malfunction indicator light (MIL) illumination and potential for frontal air bag non-deployment in several vehicles manufactured by General Motors (GM). The vehicles included model year (MY) 2020 through 2021 CT4 and CT5 passenger cars, Sierra and Silverado trucks (1500/2500/3500 models), XT4 and MY 2021 Escalade, Suburban, Tahoe, Yukon SUVs.Technical Service Bulletin (TSB) 21-NA-005, issued in March 2021, addresses air bag MIL illumination with diagnostic trouble codes (DTCs) B0001-1B or B0012-0D. It cites rust particles in the connection terminal interface of the driver air bag inflator housing as the cause of the air bag MIL illumination. Illumination of the air bag MIL under these circumstances may result in a non-deployment of the frontal driver air bag during a frontal collision and increased risk of injury to the driver.GM stated a correlation exists between production delays due to the pandemic shutdown and premature corrosion initiation on the surface of the air bag inflator housing, which, in some cases, caused rust development during a seven (7) month period of vehicle production. In the rare instance when a rust particle dislodges from the driver air bag inflator housing and enters the air bag connector prior to assembly, an intermittent resistance spike at the air bag connector may result. The condition generates excessive resistance in the air bag electrical system when the steering wheel horn cover is manipulated or the steering wheel is turned. This excessive resistance is momentary. A crash commanding air bag deployment would need to occur exactly when the momentary excessive resistance occurs. Thus, there is a very low likelihood the hazard will present a risk during a crash of sufficient severity to warrant a commanded deployment. This failure mechanism occurs early in life and results in an air bag MIL illumination that corresponds to a DTC warning the driver that the vehicle requires service. The vehicle's air bag remains functional while the MIL is illuminated, and the DTC is present.Once the connection of the driver air bag module to the clockspring is made at the plant, or at the dealership for service, there is no longer an opportunity for rust migration into the connection point. The connector is sealed and has gold terminals, eliminating the expectation of fretting corrosion. All subject vehicles passed standard corrosion validation testing for extensive corrosion with no issue of air bag non-deployment.There is a low rate of occurrence: 1.41 incidents per thousand vehicles (IPTV) for all related occurrences, and 0.04 IPTV for occurrences with a mention of visible rust and/or corrosion on the air bag inflator housing. The average occurrence mileage for the subject vehicles is approximately 2,100. Every occurrence related to the alleged defect experienced an air bag MIL illumination and there are no verified allegations of air bag non-deployment within all data sources.To date, there have been no reported fires, crashes, injuries, or fatalities related to this issue. In view of the low rate, and the nature of early-life failure, the high detectability of failures, and low potential hazard to drivers, this Preliminary Evaluation (PE) is closed. The closing of this investigation does not constitute a finding by NHTSA that a safety-related defect does not exist. The agency reserves the right to take additional action if warranted by new circumstances.Review the ODI reports cited above at nhtsa.gov under the following identification numbers: 11537927, 11528888, 11525020, 11521401, 11506057, 11493107, 11486767, 11441525, 11433146, 11425658, 11423440, 11385267, 11376429, 11373466, 11366995.

Air Bags:srs Malfunction Warning Lamp/light

On April 9, 2021, the Office of Defects Investigations (ODI) opened PE21-010 to investigate instances of air bag malfunction indicator light (MIL) illumination and potential for frontal air bag non-deployment in several vehicles manufactured by General Motors (GM). The vehicles included model year (MY) 2020 through 2021 CT4 and CT5 passenger cars, Sierra and Silverado trucks (1500/2500/3500 models), XT4 and MY 2021 Escalade, Suburban, Tahoe, Yukon SUVs.Technical Service Bulletin (TSB) 21-NA-005, issued in March 2021, addresses air bag MIL illumination with diagnostic trouble codes (DTCs) B0001-1B or B0012-0D. It cites rust particles in the connection terminal interface of the driver air bag inflator housing as the cause of the air bag MIL illumination. Illumination of the air bag MIL under these circumstances may result in a non-deployment of the frontal driver air bag during a frontal collision and increased risk of injury to the driver.GM stated a correlation exists between production delays due to the pandemic shutdown and premature corrosion initiation on the surface of the air bag inflator housing, which, in some cases, caused rust development during a seven (7) month period of vehicle production. In the rare instance when a rust particle dislodges from the driver air bag inflator housing and enters the air bag connector prior to assembly, an intermittent resistance spike at the air bag connector may result. The condition generates excessive resistance in the air bag electrical system when the steering wheel horn cover is manipulated or the steering wheel is turned. This excessive resistance is momentary. A crash commanding air bag deployment would need to occur exactly when the momentary excessive resistance occurs. Thus, there is a very low likelihood the hazard will present a risk during a crash of sufficient severity to warrant a commanded deployment. This failure mechanism occurs early in life and results in an air bag MIL illumination that corresponds to a DTC warning the driver that the vehicle requires service. The vehicle's air bag remains functional while the MIL is illuminated, and the DTC is present.Once the connection of the driver air bag module to the clockspring is made at the plant, or at the dealership for service, there is no longer an opportunity for rust migration into the connection point. The connector is sealed and has gold terminals, eliminating the expectation of fretting corrosion. All subject vehicles passed standard corrosion validation testing for extensive corrosion with no issue of air bag non-deployment.There is a low rate of occurrence: 1.41 incidents per thousand vehicles (IPTV) for all related occurrences, and 0.04 IPTV for occurrences with a mention of visible rust and/or corrosion on the air bag inflator housing. The average occurrence mileage for the subject vehicles is approximately 2,100. Every occurrence related to the alleged defect experienced an air bag MIL illumination and there are no verified allegations of air bag non-deployment within all data sources.To date, there have been no reported fires, crashes, injuries, or fatalities related to this issue. In view of the low rate, and the nature of early-life failure, the high detectability of failures, and low potential hazard to drivers, this Preliminary Evaluation (PE) is closed. The closing of this investigation does not constitute a finding by NHTSA that a safety-related defect does not exist. The agency reserves the right to take additional action if warranted by new circumstances.Review the ODI reports cited above at nhtsa.gov under the following identification numbers: 11537927, 11528888, 11525020, 11521401, 11506057, 11493107, 11486767, 11441525, 11433146, 11425658, 11423440, 11385267, 11376429, 11373466, 11366995.