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2011 GMC Sierra 2500

Owner reports · Recalls · Investigations

Similar to other model years

Owner complaints for the 2011 GMC Sierra 2500 do not stand out strongly from the model-year median of 46.

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How this year compares

Owner complaints by model year

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

What owners reported most

All reported categories

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

When problems were reported

Mileage at the reported incident

34 reports with mileage · 29 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 20 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Structure. Review the 11 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Electrical System. Review the 9 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →

NHTSA owner reports · September 18, 2026 snapshot.

1 crash reports1 fire reports1 injury reports

What owners actually said

63 reports
Mileage unknown · Apr 25, 2022
Fuel/propulsion System

On 4/12/22, we were towing our 32ft trailer with putt 2011 diesel GMC Sierra truck to Big Bear Lake which is in the San Bernardino Mountains in a two way winding highway. Upon making a somewhat sharp turn up a steep uphill, our accelerator went out. We had my mother in law, our two kids and dog in the vehicle at the time. We wer…

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On 4/12/22, we were towing our 32ft trailer with putt 2011 diesel GMC Sierra truck to Big Bear Lake which is in the San Bernardino Mountains in a two way winding highway. Upon making a somewhat sharp turn up a steep uphill, our accelerator went out. We had my mother in law, our two kids and dog in the vehicle at the time. We were able to get a speed of about 5-10mph to get a turn out and turn back around. We had no reception to call for help. The accelerator gave out shortly after but we were able to ride the decline to the bottom of the mountain and as soon as we were getting to the bottom, the engine turned off on us. Although it was still a two way highway, thankfully there was an emergency lane where we were able to park and where we were able to get very limited reception to call AAA (tow truck). There were vehicle speeding past us in high rates of speed. Because we needed a specialty tow truck given the towing of the truck/trailer, we knew it would take quite a while in the mountains for a driver to get to us. Temperatures at night in this area can get to 10-20 degrees. Five hours later at 11pm we were towed home. Upon towing the truck and trailer home, we were made aware of the reason the truck broke down through a diesel mechanic, which was CP4 fuel pump failure. Upon learning this and going online, we found out this is common for this truck with the CP4 fuel pump. We also found that other companies have made recalls, eg. Dodge but GMC/Chevy has not. This is obviously a safety issue that could have been catastrophic for myself, my kids and family and am wondering why there hasn’t already been a recall through GMC. Please let me know what our recourse is or if you have any questions.

NHTSA ODI #11462106

Mileage unknown · Apr 4, 2022
Electrical SystemService Brakes

My ABS and traction control and stabiltrak and service trailer break system keep going on and off its the most distracting thing i have a video of the chime not stopping. My water in fuel sensor won't go off I have un plugged it and changed it and the filter and when I unplug it it stays On

NHTSA ODI #11459515

190,000 miles · Jan 26, 2022
Electrical SystemPower TrainTraction Control System

The contact owns a 2011 GMC Sierra 2500. The contact stated that while starting the vehicle, the vehicle remained in the PARK and failed to shift into DRIVE. The steering wheel was locked preventing the gear shifter from going into gear. The traction control warning light was flashing. The vehicle was taken to the local dealer b…

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The contact owns a 2011 GMC Sierra 2500. The contact stated that while starting the vehicle, the vehicle remained in the PARK and failed to shift into DRIVE. The steering wheel was locked preventing the gear shifter from going into gear. The traction control warning light was flashing. The vehicle was taken to the local dealer but, was not diagnosed or repaired. The manufacturer was not contacted. The approximate failure mileage was 190,000. The VIN was not available.

NHTSA ODI #11448969

Mileage unknown · Sep 6, 2021
Tires

While traveling at 65 mph the vehicle began to Vibrate and suddenly the tread separated and began banging against the side of the vehicle LT265/60R20E. I feel fortunate this was a rear tire and I was able to safely bring the vehicle to a stop. The tires were installed at 35333 miles so they only had about 26000 miles and are …

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While traveling at 65 mph the vehicle began to Vibrate and suddenly the tread separated and began banging against the side of the vehicle LT265/60R20E. I feel fortunate this was a rear tire and I was able to safely bring the vehicle to a stop. The tires were installed at 35333 miles so they only had about 26000 miles and are rated to 60000 miles.

NHTSA ODI #11431869

Mileage unknown · Jul 11, 2021
Structure

Unlocked driver door will not open from the inside and trapping the occupant.

NHTSA ODI #11424304

Mileage unknown · May 3, 2021
Air Bags

TL* TAKATA RECALL. THE CONTACT OWNS A 2011 GMC SIERRA 2500. THE CONTACT RECEIVED NOTIFICATION OF NHTSA CAMPAIGN NUMBER: 21V054000 (AIR BAGS) HOWEVER, THE PART TO DO THE RECALL REPAIR WAS UNAVAILABLE. CAPPELLINO BUICK GMC (5411 TRANSIT RD, BUFFALO, NY 14221, (716) 650-4471) WAS CONTACTED AND CONFIRMED THAT THE PART WAS NOT YET AV…

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TL* TAKATA RECALL. THE CONTACT OWNS A 2011 GMC SIERRA 2500. THE CONTACT RECEIVED NOTIFICATION OF NHTSA CAMPAIGN NUMBER: 21V054000 (AIR BAGS) HOWEVER, THE PART TO DO THE RECALL REPAIR WAS UNAVAILABLE. CAPPELLINO BUICK GMC (5411 TRANSIT RD, BUFFALO, NY 14221, (716) 650-4471) WAS CONTACTED AND CONFIRMED THAT THE PART WAS NOT YET AVAILABLE. THE CONTACT STATED THAT THE MANUFACTURER HAD EXCEEDED A REASONABLE AMOUNT OF TIME FOR THE RECALL REPAIR. THE MANUFACTURER WAS NOT MADE AWARE OF THE ISSUE. THE CONTACT HAD NOT EXPERIENCED A FAILURE. VIN TOOL CONFIRMS PARTS NOT AVAILABLE.

NHTSA ODI #11414961

Mileage unknown · Apr 22, 2021
Air Bags

NO DEALER CAN REPAIR MY TAKATA AIR BAG DUE TO GM NOT HAVING A REPLACEMENT PART AVAILABLE. I AM CONCERNED THAT NHTSA AND GM ARE NOT CONCERNED FOR MY LIFE BY HAVING THIS ISSUE OPEN FOR SO LONG AND ANSWER TO THE MANDATED REPAIRS. I WILL FOLLOW UP WITH MY CONGRESSMAN AND SENATORS. I AM AFRAID WHEN I HAVE TO DRIVE AND DON'T HAVE OTHE…

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NO DEALER CAN REPAIR MY TAKATA AIR BAG DUE TO GM NOT HAVING A REPLACEMENT PART AVAILABLE. I AM CONCERNED THAT NHTSA AND GM ARE NOT CONCERNED FOR MY LIFE BY HAVING THIS ISSUE OPEN FOR SO LONG AND ANSWER TO THE MANDATED REPAIRS. I WILL FOLLOW UP WITH MY CONGRESSMAN AND SENATORS. I AM AFRAID WHEN I HAVE TO DRIVE AND DON'T HAVE OTHER OPTIONS FOR WORK.

NHTSA ODI #11413377

Mileage unknown · Mar 11, 2021
Air Bags

TL* TAKATA RECALL. THE CONTACT OWNS A 2011 GMC SIERRA 2500. THE CONTACT RECEIVED NOTIFICATION OF NHTSA CAMPAIGN NUMBER: 21V050000 (AIR BAGS) HOWEVER, THE PART TO DO THE RECALL REPAIR WAS UNAVAILABLE. THE CONTACT SPOKE TO WEST POINT BUICK GMC (16835 KATY FWY, HOUSTON, TX 77094, (281) 406-3550) WHERE IT WAS CONFIRMED THAT THE PART…

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TL* TAKATA RECALL. THE CONTACT OWNS A 2011 GMC SIERRA 2500. THE CONTACT RECEIVED NOTIFICATION OF NHTSA CAMPAIGN NUMBER: 21V050000 (AIR BAGS) HOWEVER, THE PART TO DO THE RECALL REPAIR WAS UNAVAILABLE. THE CONTACT SPOKE TO WEST POINT BUICK GMC (16835 KATY FWY, HOUSTON, TX 77094, (281) 406-3550) WHERE IT WAS CONFIRMED THAT THE PART WAS YET NOT AVAILABLE. THE CONTACT STATED THAT THE MANUFACTURER HAD EXCEEDED A REASONABLE AMOUNT OF TIME FOR THE RECALL REPAIR. THE MANUFACTURER WAS NOT MADE AWARE OF THE ISSUE. THE CONTACT HAD NOT EXPERIENCED A FAILURE. VIN TOOL CONFIRMS PARTS NOT AVAILABLE.

NHTSA ODI #11400311

180,000 miles · Feb 23, 2021
Electrical SystemEngineExterior LightingFire

THE VEHICLE ABRUPTLY CAUGHT FIRE WHILE DRIVING ON FEBRUARY 20TH 2021. THE REASON REMAINS UNKNOWN. PLEASE SEE ATTACHED IMAGES.

NHTSA ODI #11397571

54,000 miles · Dec 4, 2020
Air BagsSeat BeltsCrashInjury

TO AVOID A HEAD ON COLLISION I HAD TO MOVE TO THE RIGHT OF MY LANE AND I HIT A MOUNTAIN HEAD ON AND NEITHER THE DRIVER OR PASSENGERS AIRBAG DEPLOYED. THE VEHICLE OVER TURNED ON ITS LEFT DRIVER SIDE AFTER SKIDDING ALONG PAVEMENT FOR A FEW YARDS IT FINALLY CAME TO A STOP. THERE WERE NO PASSENGERS. I WAS THE DRIVER AND SUSTAINED L…

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TO AVOID A HEAD ON COLLISION I HAD TO MOVE TO THE RIGHT OF MY LANE AND I HIT A MOUNTAIN HEAD ON AND NEITHER THE DRIVER OR PASSENGERS AIRBAG DEPLOYED. THE VEHICLE OVER TURNED ON ITS LEFT DRIVER SIDE AFTER SKIDDING ALONG PAVEMENT FOR A FEW YARDS IT FINALLY CAME TO A STOP. THERE WERE NO PASSENGERS. I WAS THE DRIVER AND SUSTAINED LACERATIONS TO MY HEAD BRUISING IN CHEST AREA AND A PUNCTURED LEFT LUNG. THE VEHICLE WAS IN MOTION GOING 35 MPH

NHTSA ODI #11377984

Official recalls

4

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.

14V407000 · Electrical System

Jul 2, 2014

General Motors LLC (GM) is recalling certain model year 2007-2011 Chevrolet Silverado HD 2500/3500 trucks manufactured January 18, 2007, to June 22, 2011, and GMC Sierra HD 2500/3500 trucks manufactured January 22, 2007, to June 21, 2011, and equipped with an auxiliary battery. Owners may unknowingly draw too much current through the vehicle's trailer harness resulting in the melting of fusible link for the auxiliary battery.

Consequence & remedy

Consequence: If the fusible link melts it may come into contact with adjacent components, damage the electrical center cover, the nearby wiring harness conduit and other vehicle components, increasing the risk of a fire.

Remedy: GM will notify owners and dealers will replace the jumper harness with one that includes a 40 amp inline fuse, and provide the owner with supplemental Owner Manual information, free of charge. The recall began on August 29, 2014. 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 14260.

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

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.