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2011 GMC Sierra 1500

Owner reports · Recalls · Investigations

Similar to other model years

Owner complaints for the 2011 GMC Sierra 1500 do not stand out strongly from the model-year median of 181.

About this comparison →

When problems were reported

Mileage at the reported incident

151 reports with mileage · 133 unknown

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.

  • Air Bags. Review the 113 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Structure. Review the 45 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Power Train. Review the 24 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →

NHTSA owner reports · September 18, 2026 snapshot.

5 crash reports3 fire reports5 injury reports

What owners actually said

284 reports
Mileage unknown · Sep 21, 2022
Service BrakesUnknown Or Other

I towed a U-Haul trailer for four hours from Winter Springs, FL to Tallahassee, FL 08/18/2022. On the way back to Winter Springs, FL on 08/21/2022, I began to hear the dings and a message to service the trailer brake system. I had the vehicle looked at to determine the problem. The fuse was determined to be good, the ground wir…

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I towed a U-Haul trailer for four hours from Winter Springs, FL to Tallahassee, FL 08/18/2022. On the way back to Winter Springs, FL on 08/21/2022, I began to hear the dings and a message to service the trailer brake system. I had the vehicle looked at to determine the problem. The fuse was determined to be good, the ground wire was secure and not damaged, and the relay was functioning. I have been told that it may be a defective wire harness which could lead to other safety issues while operating the vehicle. The constant dinging and the blocking of vital messaging by the warning is a distraction and safety issue. A recall should be issued to correct this safety defect.

NHTSA ODI #11485624

Mileage unknown · Aug 14, 2022
Unknown Or Other

Frame rusting away and cracking. On left side in front of EVAP canister. Noticed it on 8/14/22.

NHTSA ODI #11479270

Mileage unknown · Jul 6, 2022
Air Bags

No Airbags

NHTSA ODI #11472599

Mileage unknown · Jun 29, 2022
Unknown Or Other

The entire frame of truck has rusted through.

NHTSA ODI #11471610

72,000 miles · Mar 24, 2022
Air Bags

The contact owns a 2011 GMC Sierra 1500. The contact stated that the air bag warning light was illuminated. The contact later received notification of NHTSA Campaign Number: 21V054000 (Air Bags). The vehicle was taken to the dealer where the front passenger's side air bag was replaced; however, the air bag warning light remained…

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The contact owns a 2011 GMC Sierra 1500. The contact stated that the air bag warning light was illuminated. The contact later received notification of NHTSA Campaign Number: 21V054000 (Air Bags). The vehicle was taken to the dealer where the front passenger's side air bag was replaced; however, the air bag warning light remained illuminated. The dealer informed the contact that the failure could be associated with the front driver's side air bag; however, there was no recall for the front driver's side air bag. The vehicle was not diagnosed or repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 72,000.

NHTSA ODI #11458152

302,984 miles · Mar 1, 2022
TiresInjury

The contact owns a 2011 GMC Sierra 1500 equipped with Goodyear Tires, Tire Line: Wrangler 12th Grade Pro, Tire Size: 265/70/R17, DOT Number: PJAH35HV3518. The contact stated while her friend was driving approximately 40-45 MPH with her seated in the passenger’s side seat, the passenger's side front tire experienced tread separat…

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The contact owns a 2011 GMC Sierra 1500 equipped with Goodyear Tires, Tire Line: Wrangler 12th Grade Pro, Tire Size: 265/70/R17, DOT Number: PJAH35HV3518. The contact stated while her friend was driving approximately 40-45 MPH with her seated in the passenger’s side seat, the passenger's side front tire experienced tread separation. The passenger's side curtain airbags, the driver's side curtain airbags, and the airbag located at the edge of the driver's seat deployed. The emergency fuel shut-off valve failed to engage. There were no warning lights illuminated. The contact sustained injuries on her right arm, and her friend sustained injuries to the face. Medical assistance was not needed. The driver veered to the side of the roadway. The driver was able to drive the vehicle to the nearby hotel as the tire was not totally deflated. The contact stated that only the outer layer of the tire had separated. Upon attempting to use both the front driver's seat belt and the front passenger's seat belt the next morning, the contact noticed that they had seized and would not retract nor extend. The vehicle was not diagnosed or repaired. The dealer and manufacturer were not notified of the failure. The tire dealer and manufacturer were not notified of the failure. The tire was replaced with a spare tire. The tire was a replacement tire. The vehicle failure mileage was approximately 302,984. The tire failure mileage was approximately 15,000.

NHTSA ODI #11454748

201,000 miles · Feb 28, 2022
FirerelatedFire

The contact owned a 2011 GMC Sierra 1500. The contact stated that while the vehicle was parked at the residence overnight, the vehicle caught on fire. The fire spread to his other vehicle, a 2000 Chevrolet Blazer, and that vehicle was also destroyed. The fire department was able to extinguish the fire. A fire department report w…

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The contact owned a 2011 GMC Sierra 1500. The contact stated that while the vehicle was parked at the residence overnight, the vehicle caught on fire. The fire spread to his other vehicle, a 2000 Chevrolet Blazer, and that vehicle was also destroyed. The fire department was able to extinguish the fire. A fire department report was filed. The contact was informed that the cause of the fire ignition was unintentional. Both vehicles remained at the contact's residence and were deemed totaled by the insurance company. The dealer was made aware of the failure and informed the contact that the vehicle was included in NHTSA Campaign Number: 21V054000 (Air Bags) however, the cause of the fire was not related to the failure. The manufacturer was not made aware of the failure. The failure mileage was approximately 201,000.

NHTSA ODI #11454560

Mileage unknown · Jan 11, 2022
Steering

The power steering failed while operating the vehicle. Unsafe. Local GMC dealership Haggerty in Oak Lawn, IL not able to diagnose problem after fact. My safety and others were at risk. Not confirmed, as techs are not familiar with system. No warnings prior to power steering failure. Be advised, this is a hybrid pickup, and…

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The power steering failed while operating the vehicle. Unsafe. Local GMC dealership Haggerty in Oak Lawn, IL not able to diagnose problem after fact. My safety and others were at risk. Not confirmed, as techs are not familiar with system. No warnings prior to power steering failure. Be advised, this is a hybrid pickup, and as such, does not have a traditional power steering pump system. Other GM models from the same era have had recalls, but the Silverados and Sierras were somehow omitted. The power steering assist motor has failed. Not the "brains", module.

NHTSA ODI #11446999

Mileage unknown · Oct 29, 2021
Air Bags

Takata Recall. The contact owns a 2011 GMC Sierra 1500. The contact received a recall notification for NHTSA Campaign Number: 21V054000 (Air Bags) however, the part to do the recall repair was not yet available. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The dealer an…

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Takata Recall. The contact owns a 2011 GMC Sierra 1500. The contact received a recall notification for NHTSA Campaign Number: 21V054000 (Air Bags) however, the part to do the recall repair was not yet available. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The dealer and the manufacturer were not notified of the issue. The contact had not experienced a failure. VIN tool confirms parts are not available.

NHTSA ODI #11438642

112,000 miles · Oct 1, 2021
Air Bags

The contact owns a 2011 GMC Sierra 1500. The contact stated while starting the vehicle, the air bag warning light was illuminated. The contact took the vehicle to a local dealer to be diagnosed. The contact was informed that the driver’s side air bag needed to be replaced. The vehicle was not replaced. The manufacturer was not m…

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The contact owns a 2011 GMC Sierra 1500. The contact stated while starting the vehicle, the air bag warning light was illuminated. The contact took the vehicle to a local dealer to be diagnosed. The contact was informed that the driver’s side air bag needed to be replaced. The vehicle was not replaced. The manufacturer was not made aware of the failure. The failure mileage was approximately 112,000.

NHTSA ODI #11435128

Official recalls

5

21V050000 · Air Bags:frontal:passenger Side:inflator Module

Feb 5, 2021

General Motors, LLC (GM) is recalling certain 2007-2011 Cadillac Escalade, Escalade ESV, Escalade EXT, Chevrolet Avalanche, Silverado 1500, Suburban, Tahoe, GMC Sierra 1500, Yukon, Yukon XL, and 2009-2011 Chevrolet Silverado 2500, Silverado 3500, GMC Sierra 2500 and Sierra 3500 vehicles originally sold, or ever registered, in the states of Alabama, California, Florida, Georgia, Hawaii, Louisiana, Mississippi, South Carolina, Texas, Puerto Rico, American Samoa, Guam, the Northern Mariana Islands (Saipan), and the U.S. Virgin Islands or "Zone A." Additionally, GM is recalling certain 2007-2008 Cadillac Escalade, Escalade ESV, Escalade EXT, Chevrolet Avalanche, Silverado 1500, Suburban, Tahoe, GMC Sierra 1500, Yukon, Yukon XL vehicles originally sold, or ever registered, in the states of Arizona, Arkansas, Delaware, District of Columbia, Illinois, Indiana, Kansas, Kentucky, Maryland, Missouri, Nebraska, Nevada, New Jersey, New Mexico, North Carolina, Ohio, Oklahoma, Pennsylvania, Tennessee, Virginia, and West Virginia or "Zone B." These vehicles are equipped with non-desiccated passenger frontal inflators containing phase-stabilized ammonium nitrate (PSAN) propellant. These inflators may explode due to propellant degradation occurring after long-term exposure to high absolute humidity, high temperatures, and high temperature cycling.

Consequence & remedy

Consequence: An inflator explosion may result in sharp metal fragments striking the driver or other occupants, resulting in serious injury or death.

Remedy: GM will notify owners, and dealers will replace the front passenger air bag inflator with an alternate one, free of charge. Interim letters notifying owners of the safety risk were mailed on February 22, 2021. Second notification letters will be mailed once the remedy is available. Owner notification letters were mailed on March 1, 2021. Owners may contact Chevrolet customer service at 1-800-222-1020; Cadillac customer service at 1-800-458-8006; and GMC customer service at 1-800-462-8782. GM's number for this recall is N212328760.

21V054000 · Air Bags:frontal:passenger Side:inflator Module

Feb 5, 2021

General Motors, LLC (GM) is recalling certain 2014 Cadillac Escalade, Escalade ESV, Chevrolet Silverado 2500, Silverado 3500, Suburban, Tahoe, GMC Sierra 2500, Sierra 3500, Yukon, and Yukon XL vehicles originally sold, or ever registered, in the states of AL, CA, FL, GA, HI, LA, MS, SC, TX, PR, AS, GU, the MP, and VI or "Zone A." Additionally GM is recalling certain 2011-2014 Cadillac Escalade, Escalade ESV, Chevrolet Silverado 2500, Silverado 3500, Suburban, Tahoe, GMC Sierra 2500, Sierra 3500, Yukon, Yukon XL and 2011-2013 Cadillac Escalade EXT, Chevrolet Avalanche, Silverado 1500, and GMC Sierra 1500 vehicles originally sold, or ever registered, in the states of AZ, AR, DE, DC, IL, IN, KS, KY, MD, MO, NE, NV, NJ, NM, NC, OH, OK, PA, TN, VA, and WV or "Zone B." Additionally, GM is recalling certain 2010-2014 Cadillac Escalade, Escalade ESV, Chevrolet Silverado 2500, Silverado 3500, Suburban, Tahoe, GMC Sierra 2500, Sierra 3500, Yukon, and Yukon XL and 2010-2013 Cadillac Escalade EXT, Chevrolet Avalanche, Silverado 1500, and GMC Sierra 1500 vehicles originally sold, or ever registered, in the states of AK, CO, CT, ID, IA, ME, MA, MI, MN, MT, NH, NY, ND, OR, RI, SD, UT, VT, WA, WI, and WY or "Zone C." These vehicles are equipped with non-desiccated passenger frontal inflators containing phase-stabilized ammonium nitrate (PSAN) propellant. These inflators may explode due to propellant degradation occurring after long-term exposure to high absolute humidity, high temperatures, and high temperature cycling.

Consequence & remedy

Consequence: An inflator explosion may result in sharp metal fragments striking the driver or other occupants, resulting in serious injury or death.

Remedy: GM will notify owners, and dealers will replace the front passenger air bag inflator with an alternate one, free of charge. Interim letters notifying owners of the safety risk were mailed on February 25, 2021. Second notification letters will be mailed once the remedy is available. Owner notification letters were mailed to 40 VIN owners on May 11, 2021. A second owner notification letter was mailed to all other owners on January 24, 2022. Owners may contact Chevrolet customer service at 1-800-222-1020; Cadillac customer service at 1-800-458-8006; and GMC customer service at 1-800-462-8782. GM's number for this recall is N212328800.

18V267000 · Equipment

Apr 26, 2018

General Motors LLC (GM) is recalling certain 2009-2014 Chevrolet Silverado HD and GMC Sierra HD, 2009 GMC Topkick 5000, 6000, 7000 and 8000 Series and Isuzu F Series, and 2009-2018 Chevrolet Express, and GMC Savana vehicles, equipped with certain Plastic-Handle Fire Extinguishers or Push Button 'Pindicator' Fire Extinguishers. These extinguishers may become clogged, preventing the extinguisher from discharging as expected or requiring excessive force to activate the extinguisher. Additionally, in certain models, the nozzle may detach from the valve assembly with enough force that it could cause injury and also render the product inoperable. For a full list of the affected fire extinguisher models visit: https://static.nhtsa.gov/odi/rcl/2017/RMISC-17E062-5427.pdf

Consequence & remedy

Consequence: In the event of a fire, if the fire extinguisher does not function properly, it can increase the risk of injury.

Remedy: GM will notify owners, instructing them to contact Kidde to get a replacement fire extinguisher, free of charge. The recall began June 11, 2018. Owners may contact Chevrolet customer service at 1-800-222-1020, GMC customer service at 1-800-462-8782, and Isuzu customer service at 1-866-441-9638. GM's number for this recall is 18146.

11V007000 · Suspension:rear:axle:spindle

Jan 6, 2011

GENERAL MOTORS IS RECALLING CERTAIN MODEL YEAR 2011 CADILLAC ESCALADE, ESCALADE ESV, ESCALADE EXT; CHEVROLET AVALANCHE, COLORADO, EXPRESS, SILVERADO, SUBURBAN, TAHOE; AND GMC CANYON, SIERRA, SAVANA, YUKON AND YUKON XL VEHICLES. THE REAR AXLE CROSS PINS WERE NOT PROPERLY HEAT TREATED AND COULD FRACTURE AND BECOME DISPLACED WITHIN THE REAR AXLE. SHOULD THE PIN SHIFT OUT OF POSITION, IT COULD CREATE AN INTERFERENCE CONDITION AND CAUSE THE REAR AXLE TO LOCK.

Consequence & remedy

Consequence: THE DRIVER MAY NOT BE ABLE TO MAINTAIN DIRECTIONAL CONTROL OF THE VEHICLE AND A CRASH COULD OCCUR WITHOUT WARNING.

Remedy: DEALERS WILL INSTALL A NEW REAR AXLE CROSS PIN FREE OF CHARGE. THE SAFETY RECALL BEGAN ON JANUARY 11, 2011. OWNERS MAY CONTACT CADILLAC AT 1-866-982-2339, CHEVROLET AT 1-800-630-2438, GMC AT 1-866-996-9463 AND AT THE OWNER CENTER AT WWW.GMOWNERCENTER.COM.

10V643000 · Suspension:rear:axle:spindle

Dec 17, 2010

GENERAL MOTORS IS RECALLING CERTAIN MODEL YEAR 2011 CADILLAC ESCALADE EXT, CHEVROLET AVALANCHE, SILVERADO LD AND GMC SIERRA LD VEHICLES. THE REAR AXLE CROSS PINS WERE NOT PROPERLY HEAT TREATED AND COULD FRACTURE AND BECOME DISPLACED WITHIN THE REAR AXLE. SHOULD THE PIN SHIFT OUT OF POSITION, IT COULD CREATE AN INTERFERENCE CONDITION AND CAUSE THE REAR AXLE TO LOCK.

Consequence & remedy

Consequence: THE DRIVER MAY NOT BE ABLE TO MAINTAIN DIRECTIONAL CONTROL OF THE VEHICLE AND A CRASH COULD OCCUR WITHOUT WARNING.

Remedy: DEALERS WILL INSTALL A NEW REAR AXLE CROSS PIN FREE OF CHARGE. THE SAFETY RECALL BEGAN ON JANUARY 11, 2011. OWNERS MAY CONTACT CADILLAC AT 1-866-982-2339, CHEVROLET AT 1-800-630-2438, GMC AT 1-866-996-9463 AND AT THE OWNER CENTER AT WWW.GMOWNERCENTER.COM.

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

2

DP22005 · Pedestrian Alert Sounds

Opened Jan 27, 2023 · Closed Aug 7, 2023

Status: closed (inferred from source dates) · Electrical System:propulsion System

NHTSA received a petition on or about July 18, 2022, requesting that Federal Motor Vehicle Safety Standard (FMVSS) 141 be applied to all electric and hybrid vehicles operating in the United States. The petition can be reviewed at NHTSA.gov under ODI Number 11486072. FMVSS 141 establishes performance requirements for pedestrian alert sounds for motor vehicles. The standard applies to hybrid and electric vehicles that have a gross vehicle weight rating of 4,536 KG or less or are defined as low-speed vehicles. The standard became fully applicable to all such vehicles manufactured on or after March 1, 2021.On January 27, 2023, NHTSA opened Defect Petition (DP) 22-005 to evaluate the subject matter described in the petition. On June 24, 2023 and as supplemented on June 25, 2023, the petitioner notified NHTSA he was withdrawing his petition. The petitioner indicated that, based on his review of data, there is no justification for asserting potential benefits that could be derived from actions sought by my petition. Based on the petitioner's withdrawal, DP22-005 is closed. Closure of this DP does not represent a determination by NHTSA regarding the subject matter of the petition.

EA21002 · Desiccated Air Bag Inflator Rupture

Opened Sep 17, 2021 · No close date supplied

Status: open (inferred from source dates) · Air Bags:frontal:driver Side:inflator Module; Air Bags:frontal:passenger Side:inflator Module

From 2000 through 2017, Takata produced millions of air bag inflators using two types of phase-stabilized ammonium nitrate ("PSAN") propellant -- propellant 2004 and propellant 2004L. After prolonged exposure to high temperature cycles and humidity, inflators using propellant 2004 can degrade, causing the propellant to burn too quickly when ignited. The rapid burning can cause the inflator to rupture during deployment, potentially causing serious or even fatal injury to vehicle occupants. See 2016 Blomquist Report at www.nhtsa.gov/sites/nhtsa.gov/files/documents/expert_report-hrblomquist.pdf.Consequently, all frontal inflators using propellant 2004 that do not contain a "desiccant" (a substance that traps and holds moisture) in US vehicles are under recall. These "non-desiccated" inflators either have been or are required to be replaced.In some cases, the remedy part for these recalled inflators was, or will be, an inflator using either propellant 2004 or 2004L that does contain a desiccant. None of these "desiccated" remedy parts (which were installed in older model year vehicles) are currently under recall for a degradation concern. Certain subsets of desiccated PSAN inflators using propellant 2004 for use as original equipment, however, have been recalled for a degradation concern. All Takata inflators produced with propellant 2004L contain desiccant, and none of these desiccated inflators using propellant 2004L are under recall for a degradation concern. There have been no reported field ruptures in any non-recalled desiccated PSAN inflators.It is understood that desiccants fully saturate at some threshold, at which point any additional moisture will not be captured. This means the degradation process observed in non-desiccated inflators using propellant 2004 may also occur in non-recalled desiccated inflators using propellant 2004, assuming additional moisture enters the inflator and high temperature cycling occurs. Based on available information, desiccant saturation can occur within the first five years in the worst environments, and the time required for full saturation is affected by multiple factors. While no present safety risk has been identified, further work is needed to evaluate the future risk of non-recalled desiccated inflators using propellant 2004.Three entities -- Takata (now known as TK Global), the Independent Testing Coalition, and Exponent -- have been studying the long-term behavior of Takata desiccated PSAN inflators using propellant 2004L (as well as 2004) in the presence of moisture and temperature cycling. The research efforts, which include development of predictive modeling techniques and field sample analysis, are ongoing. To date, none of the researchers have identified field evidence showing that propellant 2004L is undergoing a degradation process that leads to aggressive deployment and potential rupture. However, the time in service of such inflators remains short compared to that of the inflators using propellant 2004. Further study is needed to assess the long-term safety of desiccated inflators using propellant 2004L.The Office of Defects Investigation is opening this investigation to examine whether a safety defect related to propellant degradation exists in non-recalled desiccated PSAN frontal inflators manufactured by Takata. This investigation will require extensive information on Takata production processes and surveys of inflators in the field. Lists of recall actions that may have used desiccated PSAN inflators as remedy parts, as well as the makes and models originally manufactured with them, is available with the downloadable version of this document (see nhtsa.gov/recalls?nhtsaId=EA21002 -- note this information is subject to change/revision as the investigation proceeds). This investigation does not supersede EA15-001, which remains open.

Additional source detail variants (2)

Air Bags:frontal:driver Side:inflator Module

From 2000 through 2017, Takata produced millions of air bag inflators using two types of phase-stabilized ammonium nitrate ("PSAN") propellant -- propellant 2004 and propellant 2004L. After prolonged exposure to high temperature cycles and humidity, inflators using propellant 2004 can degrade, causing the propellant to burn too quickly when ignited. The rapid burning can cause the inflator to rupture during deployment, potentially causing serious or even fatal injury to vehicle occupants. See 2016 Blomquist Report at www.nhtsa.gov/sites/nhtsa.gov/files/documents/expert_report-hrblomquist.pdf.Consequently, all frontal inflators using propellant 2004 that do not contain a "desiccant" (a substance that traps and holds moisture) in US vehicles are under recall. These "non-desiccated" inflators either have been or are required to be replaced.In some cases, the remedy part for these recalled inflators was, or will be, an inflator using either propellant 2004 or 2004L that does contain a desiccant. None of these "desiccated" remedy parts (which were installed in older model year vehicles) are currently under recall for a degradation concern. Certain subsets of desiccated PSAN inflators using propellant 2004 for use as original equipment, however, have been recalled for a degradation concern. All Takata inflators produced with propellant 2004L contain desiccant, and none of these desiccated inflators using propellant 2004L are under recall for a degradation concern. There have been no reported field ruptures in any non-recalled desiccated PSAN inflators.It is understood that desiccants fully saturate at some threshold, at which point any additional moisture will not be captured. This means the degradation process observed in non-desiccated inflators using propellant 2004 may also occur in non-recalled desiccated inflators using propellant 2004, assuming additional moisture enters the inflator and high temperature cycling occurs. Based on available information, desiccant saturation can occur within the first five years in the worst environments, and the time required for full saturation is affected by multiple factors. While no present safety risk has been identified, further work is needed to evaluate the future risk of non-recalled desiccated inflators using propellant 2004.Three entities -- Takata (now known as TK Global), the Independent Testing Coalition, and Exponent -- have been studying the long-term behavior of Takata desiccated PSAN inflators using propellant 2004L (as well as 2004) in the presence of moisture and temperature cycling. The research efforts, which include development of predictive modeling techniques and field sample analysis, are ongoing. To date, none of the researchers have identified field evidence showing that propellant 2004L is undergoing a degradation process that leads to aggressive deployment and potential rupture. However, the time in service of such inflators remains short compared to that of the inflators using propellant 2004. Further study is needed to assess the long-term safety of desiccated inflators using propellant 2004L.The Office of Defects Investigation is opening this investigation to examine whether a safety defect related to propellant degradation exists in non-recalled desiccated PSAN frontal inflators manufactured by Takata. This investigation will require extensive information on Takata production processes and surveys of inflators in the field. Lists of recall actions that may have used desiccated PSAN inflators as remedy parts, as well as the makes and models originally manufactured with them, is available with the downloadable version of this document (see nhtsa.gov/recalls?nhtsaId=EA21002 -- note this information is subject to change/revision as the investigation proceeds). This investigation does not supersede EA15-001, which remains open.

Air Bags:frontal:passenger Side:inflator Module

From 2000 through 2017, Takata produced millions of air bag inflators using two types of phase-stabilized ammonium nitrate ("PSAN") propellant -- propellant 2004 and propellant 2004L. After prolonged exposure to high temperature cycles and humidity, inflators using propellant 2004 can degrade, causing the propellant to burn too quickly when ignited. The rapid burning can cause the inflator to rupture during deployment, potentially causing serious or even fatal injury to vehicle occupants. See 2016 Blomquist Report at www.nhtsa.gov/sites/nhtsa.gov/files/documents/expert_report-hrblomquist.pdf.Consequently, all frontal inflators using propellant 2004 that do not contain a "desiccant" (a substance that traps and holds moisture) in US vehicles are under recall. These "non-desiccated" inflators either have been or are required to be replaced.In some cases, the remedy part for these recalled inflators was, or will be, an inflator using either propellant 2004 or 2004L that does contain a desiccant. None of these "desiccated" remedy parts (which were installed in older model year vehicles) are currently under recall for a degradation concern. Certain subsets of desiccated PSAN inflators using propellant 2004 for use as original equipment, however, have been recalled for a degradation concern. All Takata inflators produced with propellant 2004L contain desiccant, and none of these desiccated inflators using propellant 2004L are under recall for a degradation concern. There have been no reported field ruptures in any non-recalled desiccated PSAN inflators.It is understood that desiccants fully saturate at some threshold, at which point any additional moisture will not be captured. This means the degradation process observed in non-desiccated inflators using propellant 2004 may also occur in non-recalled desiccated inflators using propellant 2004, assuming additional moisture enters the inflator and high temperature cycling occurs. Based on available information, desiccant saturation can occur within the first five years in the worst environments, and the time required for full saturation is affected by multiple factors. While no present safety risk has been identified, further work is needed to evaluate the future risk of non-recalled desiccated inflators using propellant 2004.Three entities -- Takata (now known as TK Global), the Independent Testing Coalition, and Exponent -- have been studying the long-term behavior of Takata desiccated PSAN inflators using propellant 2004L (as well as 2004) in the presence of moisture and temperature cycling. The research efforts, which include development of predictive modeling techniques and field sample analysis, are ongoing. To date, none of the researchers have identified field evidence showing that propellant 2004L is undergoing a degradation process that leads to aggressive deployment and potential rupture. However, the time in service of such inflators remains short compared to that of the inflators using propellant 2004. Further study is needed to assess the long-term safety of desiccated inflators using propellant 2004L.The Office of Defects Investigation is opening this investigation to examine whether a safety defect related to propellant degradation exists in non-recalled desiccated PSAN frontal inflators manufactured by Takata. This investigation will require extensive information on Takata production processes and surveys of inflators in the field. Lists of recall actions that may have used desiccated PSAN inflators as remedy parts, as well as the makes and models originally manufactured with them, is available with the downloadable version of this document (see nhtsa.gov/recalls?nhtsaId=EA21002 -- note this information is subject to change/revision as the investigation proceeds). This investigation does not supersede EA15-001, which remains open.