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2013 Chevrolet Silverado 1500

Owner reports · Recalls · Investigations

Similar to other model years

Owner complaints for the 2013 Chevrolet Silverado 1500 do not stand out strongly from the model-year median of 525.

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When problems were reported

Mileage at the reported incident

170 reports with mileage · 131 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 83 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Structure. Review the 75 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Engine. Review the 33 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →

NHTSA owner reports · September 18, 2026 snapshot.

8 crash reports0 fire reports4 injury reports

Engine complaints

33 reports
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Mileage unknown · Sep 15, 2023
EngineFuel/propulsion System

Throughout this truck's lifespan, it's had multiple problems with the engine and fuel system. Around 70k miles, the engine had to be completely rebuilt because of the issues with oil consumption; well known GM 5.3 liter V8 issue. The oil consumption issue then started back up around 140k miles. Once the vehicle hit 100k miles…

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Throughout this truck's lifespan, it's had multiple problems with the engine and fuel system. Around 70k miles, the engine had to be completely rebuilt because of the issues with oil consumption; well known GM 5.3 liter V8 issue. The oil consumption issue then started back up around 140k miles. Once the vehicle hit 100k miles, it started throwing codes for running to lean and too rich, plus it showed the alcohol (ethanol) content at 40%. I've never used E85/20/15/10, but did use 3.5% blended fuel for the first 100K miles. Since then I've switched to 91 premium which does not contain ethanol. However, me readings continue to be over 40% ethanol. All physical parts of the system, that could lead to this issue have been replaced. Recently, my mechanic happened upon Bulletin PIP4792D, which speaks directly to the issue I among countless others are having. In contacting my local dealership and GM, both declined to help unless I paid to have them correct the software issue that is causing this problem. It seems strange to me that a company would expect a consumer to pay for an update to software, when the company is the one who is the cause for the software being bad.

NHTSA ODI #11544764

Mileage unknown · Aug 21, 2023
Engine

2013 Chevy Silverado has the active fuel management system, which failed and caused the cylinder 1 to have a collapsed lifter. This is a known defeat of these GM V8 5.3 lilter motors. I feel GM should be required to repair these motors free of cost to the consumer.

NHTSA ODI #11539694

Mileage unknown · Jul 12, 2023
EngineUnknown Or OtherVehicle Speed ControlInjury

Stabiltrack System, Traction Control System, Reduced Engine Power. Since purchase of the vehicle, intermittent immediate failure or previously stated vehicle systems caused critical safety concerns for occupants and other drivers while operating. Vehicle looses power enters safety "Limp Mode" due to faulty engineering. Upon insp…

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Stabiltrack System, Traction Control System, Reduced Engine Power. Since purchase of the vehicle, intermittent immediate failure or previously stated vehicle systems caused critical safety concerns for occupants and other drivers while operating. Vehicle looses power enters safety "Limp Mode" due to faulty engineering. Upon inspection by State Police and Fire/EMS, owners urged to contact vehicle manufacturer and NHTSA to report issue. Failure of system first happened around 140k miles on odometer. No safety or warning lamps were present prior to stated malfunction of vehicle. Malfunction appears now daily causing impaired drivability and serious safety concerns for occupants and fellow drivers. Messages on Dashboard State The Following. "Service Stabiltrack, Service Traction Control, Reduced Engine Power". NO Certain Cause OR Remedy from manufacturer.

NHTSA ODI #11531952

150,000 miles · May 22, 2023
EngineEngine And Engine Cooling

The contact owns a 2013 Chevrolet Silverado 1500. The contact stated that while driving at an undisclosed speed, the vehicle made rattling sounds. The vehicle was taken to the dealer, where it was diagnosed that the lifters and camshaft needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the f…

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The contact owns a 2013 Chevrolet Silverado 1500. The contact stated that while driving at an undisclosed speed, the vehicle made rattling sounds. The vehicle was taken to the dealer, where it was diagnosed that the lifters and camshaft needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure and advised the contact to file a complaint with the NHTSA Hotline. The failure mileage was approximately 150,000.

NHTSA ODI #11523182

Mileage unknown · Sep 26, 2022
EngineUnknown Or Other

I bought a 2013 silverado truck with 30,000 miles. I paid $30,000. A year and half later the engine blew. It was 3 months after warranty and I had to pay $8000 to replace. 2 yrs later I heard a very disturbing noise. Mechanic assess and said frame is rusted through. Tubing, gas tank following off. Suspension so rusted it was a m…

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I bought a 2013 silverado truck with 30,000 miles. I paid $30,000. A year and half later the engine blew. It was 3 months after warranty and I had to pay $8000 to replace. 2 yrs later I heard a very disturbing noise. Mechanic assess and said frame is rusted through. Tubing, gas tank following off. Suspension so rusted it was a miracle it didn’t just fall apart. I again bring it to Chevy (now a 3rd owner in 5yrs) and they tell me they will give me $1000. I still own almost $6000 on the loan due to the engine. There are major issues with this truck. The wax coating they used and poor steel excelled the rust at a rapid pace. If you recoated this with rust resistive spray it would void all warranties. I am now 5 years in with a blown engine and rusted through frame. Chevy has no other solution except to add my balance of that truck into a new loan and buy another. They knew this issue and had multiple opportunities to fix and /or notify. The engine also has class action in a few states because if faulty oil consumption doing damage and blowing engines. There should be some major recalls. I see hundreds upon hundred of people complaining of the same thing. Now I’m out a truck with no value. Cannot work etc. Very financially devastating. GM is incredibly dishonest and knowingly selling defective trucks.

NHTSA ODI #11486535

Mileage unknown · May 25, 2022
Electrical SystemEngineUnknown Or Other

I was told from a mechanic that the header where my spark plugs go is wrapped do to the manufacturer and is causing the spark plugs to misfire. The truck has died at a stop, is causing the truck to run horrible. I am sorry if I am not explaining it all properly. My dad bought this truck brand new in 2013 and he passed away in 2…

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I was told from a mechanic that the header where my spark plugs go is wrapped do to the manufacturer and is causing the spark plugs to misfire. The truck has died at a stop, is causing the truck to run horrible. I am sorry if I am not explaining it all properly. My dad bought this truck brand new in 2013 and he passed away in 2015 and I paid of the car so I could have the memory. So I have had it and been in the truck pretty much off the lot. its has only 95 thousand miles and has had this issue always, but I was always told problems with spark plugs and coils until now. please help

NHTSA ODI #11466052

Mileage unknown · May 23, 2022
EngineExterior LightingService Brakes

at least once a month gives a false trailer braking error and the truck brakes itself, dash dies, driver loses control over the vehicle. It is a risk of crashing or being hit because the truck stops itself in the middle of driving without brake lights coming on to alert other drivers. No way to overcome this - can't hit the ga…

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at least once a month gives a false trailer braking error and the truck brakes itself, dash dies, driver loses control over the vehicle. It is a risk of crashing or being hit because the truck stops itself in the middle of driving without brake lights coming on to alert other drivers. No way to overcome this - can't hit the gas pedal, etc. It seems to think that you are hauling a trailer and it thinks the trailer is swaying... problem is this truck has never towed a trailer even one time... it's completely false. But also very dangerous.

NHTSA ODI #11465856

Mileage unknown · Feb 21, 2022
EngineFuel/propulsion SystemVehicle Speed Control

I experienced a failure of the BOSCH 4.2 fuel rail pump while driving on Interstate 65 North near Louisville KY at night and my truck had a dead pedal and was unable to accelerate any and I was in the right lane going over a bridge and two tractor trailers were in each lane behind me and having been on the bridge I was unable to…

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I experienced a failure of the BOSCH 4.2 fuel rail pump while driving on Interstate 65 North near Louisville KY at night and my truck had a dead pedal and was unable to accelerate any and I was in the right lane going over a bridge and two tractor trailers were in each lane behind me and having been on the bridge I was unable to leave the lane of travel until I had completely transversed the bridge I was traveling over. I did engage my emergency flashers immediately but having the trucks side by side and the truck in my lane traveling at highway speeds I was almost struck from behind as the tractor trailer applied his brakes and was able to avoid the collision luckily. I took my truck to the local dealership and was told what the issue was and I had it fixed immediately. The price of the repair was $10,362.64 give or take a few dollars. I had a warranty but that company refused to pay since it's not considered part of the engine. Dodge has issued a Recall for the exact same part as far as I am understanding but yet Chevrolet/GMC has not. Thank you very much [XXX] INFORMATION Redacted PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6).

NHTSA ODI #11453267

Mileage unknown · Feb 5, 2022
Engine

Active fuel management caused my 5.3 liter v8 valve train to fail and lost compression in a few cylinders.had to replace complete motor at 120,000 miles.at mechanics now getting a new non afm jasper engine to the tune of 8000 dollars.even with impeccable maintenance.myself being the only owner.

NHTSA ODI #11450618

Mileage unknown · Apr 23, 2021
Engine

I WAS DRIVING THE TRUCK IT STARTED SHAKING, SO I TOOK IT TO THE DEALER. THEY SAID THAT THERE IS CARBON BUILD UP ON THE ENGINE. THERE IS ONLY SIXTY THOUSAND MILES ON THE VEHICLE. GMC SENT OUT A BULLETIN TO DEALERS THAT THIS IS A PROBLEM AND SUGGESTED THE SERVICE DEPT FLUSH THE ENGINE, BUT THEY CAN NOT PROMISE ANYTHING. THE DEALER…

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I WAS DRIVING THE TRUCK IT STARTED SHAKING, SO I TOOK IT TO THE DEALER. THEY SAID THAT THERE IS CARBON BUILD UP ON THE ENGINE. THERE IS ONLY SIXTY THOUSAND MILES ON THE VEHICLE. GMC SENT OUT A BULLETIN TO DEALERS THAT THIS IS A PROBLEM AND SUGGESTED THE SERVICE DEPT FLUSH THE ENGINE, BUT THEY CAN NOT PROMISE ANYTHING. THE DEALER TOLD ME THAT I DID NOT DRIVE THE TRUCK ENOUGH, SO THAT'S WHAT CAUSED THE PROBLEM. WHEN I BOUGHT THE TRUCK THEY TOLD ME THAT IT IS A VERY CLEAN RUNNING TRUCK, NOT AS MUCH POLLUTION. SO INSTEAD OF THE CARBON BLOWING OUT THE TAILPIPE IS IT STAYING IN THE ENGINE? I DO NOT THINK THAT I SHOULD HAVE TO PAY OUT ALL THIS MONEY FOR SOMETHING GMC OVER LOOKED. THIS IS A PROBLEM THEY DID NOT SEE, SO THEY SHOULD BE RESPONSIBLE FOR THE EXPENSES. I MIGHT EVEN NEED A NEW ENGINE BECAUSE THEY CAN NOT BE SURE THE FLUSHING AND OIL CHANGE WILL SOLVE THE PROBLEM AND IT CAN HAPPEN AGAIN.

NHTSA ODI #11413602

Official recalls

2

21V053000 · Air Bags:frontal:passenger Side:inflator Module

Feb 5, 2021

General Motors, LLC (GM) is recalling certain 2013 Cadillac Escalade, Escalade ESV, and Escalade EXT, Chevrolet Avalanche, Silverado 1500, Silverado 2500/3500, Suburban, Tahoe, GMC Sierra 1500, Sierra 2500/3500, Yukon, and Yukon XL 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 2010 Cadillac Escalade, Escalade ESV, and Escalade EXT, Chevrolet Avalanche, Silverado 1500, Silverado 2500/3500, Suburban, Tahoe, GMC Sierra 1500, Sierra 2500/3500, Yukon, and 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." Additionally, GM is recalling certain 2009 Cadillac Escalade, Escalade ESV, and Escalade EXT, Chevrolet Avalanche, Silverado 1500, Silverado 2500/3500, Suburban, Tahoe, GMC Sierra 1500, Sierra 2500/3500, Yukon, and Yukon XL vehicles originally sold, or ever registered, in the states of Alaska, Colorado, Connecticut, Idaho, Iowa, Maine, Massachusetts, Michigan, Minnesota, Montana, New Hampshire, New York, North Dakota, Oregon, Rhode Island, South Dakota, Utah, Vermont, Washington, Wisconsin, and Wyoming or "Zone C."

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 24, 2021. Second notification letters will be mailed once the remedy is available. Owner notification letters were mailed on May 11, 2021. Owners may contact Cadillac customer service at 1-800-458-8006; Chevrolet customer service at 1-800-222-1020; and GMC customer service at 1-800-462-8782. GM's number for this recall is N212328790.

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.

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.