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2011 Chevrolet Silverado 1500

Owner reports · Recalls · Investigations

Similar to other model years

Owner complaints for the 2011 Chevrolet Silverado 1500 do not stand out strongly from the model-year median of 525.

About this comparison →

When problems were reported

Mileage at the reported incident

263 reports with mileage · 300 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 306 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Structure. Review the 72 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Engine. Review the 40 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →

NHTSA owner reports · September 18, 2026 snapshot.

22 crash reports4 fire reports6 injury reports

Unknown Or Other complaints

115 reports
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Mileage unknown · Apr 13, 2024
Unknown Or Other

I recently had my vehicle inspected and the garage personnel told me it would pass inspection this time because there is a lot of rust on it.

NHTSA ODI #11582765

Mileage unknown · Mar 17, 2024
SuspensionUnknown Or Other

Complete structural failure of chassis (Frame). Upon inspection on a mechanics lift the frame is cracked in several places and due to the undersized structural components and type of steel resulted in extensive corrosion. All components of vehicle depend on structural integrity of support frame. The frame has been inspected by …

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Complete structural failure of chassis (Frame). Upon inspection on a mechanics lift the frame is cracked in several places and due to the undersized structural components and type of steel resulted in extensive corrosion. All components of vehicle depend on structural integrity of support frame. The frame has been inspected by several mechanics. All suspension components attached to vehicle frame are in serious jeopardy of failure. Several other Chevrolet truck owners have total losses of vehicle value to to undersized structural frame and extensive corrosion. This is a manufacturer's defect, its similar to building a house on a weak foundation.

NHTSA ODI #11577842

Mileage unknown · Feb 22, 2024
Unknown Or Other

The frame is completely rusted on this truck it has approximately 133k miles on it. In my research on this year truck there are many complaints for the same issue some through this site and others through forums. There needs to be a frame recall issued on this truck the approximate date below is when it was noticed during an ins…

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The frame is completely rusted on this truck it has approximately 133k miles on it. In my research on this year truck there are many complaints for the same issue some through this site and others through forums. There needs to be a frame recall issued on this truck the approximate date below is when it was noticed during an inspection

NHTSA ODI #11573466

Mileage unknown · Jan 13, 2024
SuspensionUnknown Or Other

Frame of truck rotted. Went to change shocks and it fell right off. Removed the bottom bolt on the shock and the 15 lbs shock fell to the ground with the top bolt still attached to the frame.2 years ago had to replace the the hitch due to rusted out Glad I was not pulling my 6000 lbs camper down the highway. The frame is so badl…

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Frame of truck rotted. Went to change shocks and it fell right off. Removed the bottom bolt on the shock and the 15 lbs shock fell to the ground with the top bolt still attached to the frame.2 years ago had to replace the the hitch due to rusted out Glad I was not pulling my 6000 lbs camper down the highway. The frame is so badly rotted it is unsafe to drive down the road. Not surface rust holes the inside of frame is rotted both sides. Unsafe to drive. Owned this truck for 9 years.

NHTSA ODI #11565259

Mileage unknown · Dec 4, 2023
Unknown Or Other

I was told when I had my oil changed that my frame is rusted and has cracks

NHTSA ODI #11558327

Mileage unknown · Nov 5, 2023
Unknown Or Other

TOOK VEHICLE TO DEALER TO GET AN ALINGMENT, THE DEALER SAID COULD NOT DO THE ALINGMENT BECAUSE FRAME WAS BROKEN, UNDER CLOSER INSPECTION FOUND OUT THAT FRAME IS RUSTED AND DETERATING IN MANY SPOT INCLUEDING REAR LEFT SECTION AND REAR RIGHT SECTIONS, ON LEFT NEAR FUEL TANK, CROSS RAIL FOR FUEL TANK, THAT ATTACH FUEL TANK TO VE…

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TOOK VEHICLE TO DEALER TO GET AN ALINGMENT, THE DEALER SAID COULD NOT DO THE ALINGMENT BECAUSE FRAME WAS BROKEN, UNDER CLOSER INSPECTION FOUND OUT THAT FRAME IS RUSTED AND DETERATING IN MANY SPOT INCLUEDING REAR LEFT SECTION AND REAR RIGHT SECTIONS, ON LEFT NEAR FUEL TANK, CROSS RAIL FOR FUEL TANK, THAT ATTACH FUEL TANK TO VEHICLE, ALSO CROSS MEMBER THAT ATTCH SHOCKS ON REAR TO TO FRAME.

NHTSA ODI #11553689

Mileage unknown · Sep 11, 2023
Unknown Or Other

I had my truck in my shop after a lot of clunking started to come from the rear suspension. I had the truck up on the lift to check out the cause, and found very disappointing news. This truck has approximately 107,000 miles on it, and should not have this much compromised structure. The body is in near perfect condition. The ve…

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I had my truck in my shop after a lot of clunking started to come from the rear suspension. I had the truck up on the lift to check out the cause, and found very disappointing news. This truck has approximately 107,000 miles on it, and should not have this much compromised structure. The body is in near perfect condition. The vehicle has always been garage kept and clean. The entire rear frame of the truck has rust scale/perforation. Multiple areas are flaking badly and have holes that are 1/2" and larger. The rearmost cross member that attaches the upper shock is rotted out and missing. The other crossmembers are in poor condition. The areas of the frame where the leaf springs attach are thin. The only solution that seems feasible is a complete stripping, reinforcement, and/or replacement of the rear frame section. I own and operate my own shop, and have the ability to do this work for myself but there is no reason I should have to fix a truck that is 12 years old. Sadly, this is not the only GM product I have seen with this type of rot. It's just unfortunate that my personal vehicle has one of the worst frames that I have encountered.

NHTSA ODI #11543965

Mileage unknown · Sep 9, 2023
StructureUnknown Or Other

On August 24, 2023 I took my 2011 Silverado WT extended cab 4X4 to a local independent service facility for a required annual safety inspection. It has failed an annual vehicle safety inspection due to frame rust through. I am scheduled with the repair shop to repair this new rust section September 12, 2023. This is the second …

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On August 24, 2023 I took my 2011 Silverado WT extended cab 4X4 to a local independent service facility for a required annual safety inspection. It has failed an annual vehicle safety inspection due to frame rust through. I am scheduled with the repair shop to repair this new rust section September 12, 2023. This is the second year in a row that it has failed due to frame rust through after having been repaired last year. The truck has 141,846 mile on it and should not be experiencing a frame issue requiring welding repairs. If I lived in a state that did not require annual safety inspections this could easily become a major safety hazard resulting in a crash with severe personal injury or death. GM should be notified and held accountable to provide necessary repairs and or compensation very similar to the Toyota Tacoma frame recall a few years back.

NHTSA ODI #11543572

Mileage unknown · Aug 21, 2023
Fuel/propulsion SystemUnknown Or Other

Fuel leak at the fuel tank. Pulled tank from the truck, found the fuel pump housing was completely rusted out. Upon inspection of the pump housing, the high pressure line was rusted out and almost off the pump, causing gasoline to pump out and all over. After replacing this fuel pump I inspected the frame and found the frame loo…

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Fuel leak at the fuel tank. Pulled tank from the truck, found the fuel pump housing was completely rusted out. Upon inspection of the pump housing, the high pressure line was rusted out and almost off the pump, causing gasoline to pump out and all over. After replacing this fuel pump I inspected the frame and found the frame looks like a frame off a truck that is 40 years old, not a truck that is only 12 years old. The frame has heavy levels of rust down thru from the drivetrain back. There are spots that are rusted completely thru the frame where it looks like a crack down the frame. Most of the rust is on the bottom side or inside area of the frame. This area with the rust crack will have to be repaired very soon for safety of the vehicle, because if the frame would happen to fail where this crack is, the truck would fold in half, and if it is being driven on the interstate it would cause a major accident for sure. The rusting is so extensive that instead of repairing the spots, it would be more feasible to just go ahead and replace the whole back half of the truck frame. This is unacceptable for Chevrolet to use material that craps out so fast on trucks that are supposed to last many years, instead of falling apart long before they are even paid off. A 12 year old truck shouldn't have this extensive amount of rust damage to the frame. I would just fix the frame if this was commonplace for trucks, but my 2000 Dodge Ram has a frame far better then what is under my 2011 Chevy Silverado as far as rust goes. 2000 Dodge surface rust in spots, 2011 Chevy completely rusted thru in spots. My next inspection on this Chevy will more then likely remove it off the road unless the frame is repaired. Unacceptable from Chevrolet and for only a 12 year old truck. I added pics of the frame right in front of the fuel tank, which the frame shows that long rusted crack down it. Can send more pictures of the frame in other places if needed.

NHTSA ODI #11539753

Mileage unknown · Apr 30, 2023
Unknown Or Other

The oil pump has been replaced and is still not working how it is supposed to.

NHTSA ODI #11519715

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.

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.