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2016 Nissan Titan Xd

Owner reports · Recalls · Investigations

Limited comparison data

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

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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

78 reports with mileage · 119 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.

  • Engine. Review the 128 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Power Train. Review the 42 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Fuel/propulsion System. Review the 31 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 reports2 fire reports2 injury reports

Engine complaints

128 reports
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Mileage unknown · Sep 5, 2026
Engine

Engine failed unexpectedly and without warning. After doing research there is a widespread problem with the 2016 diesel engine.

NHTSA ODI #11762321

Mileage unknown · Feb 25, 2026
Engine

Truck died while traveling at 60MPH, once safely pulled over saw it shutdown due to low oil pressure. Checked the oil level and found correct level on dipstick. Attempted to start, no start. Towed to shop, they drained the oil and verified correct oil quantity cam out. Pulled the oil pan and found metal in the oil pan. Told I ne…

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Truck died while traveling at 60MPH, once safely pulled over saw it shutdown due to low oil pressure. Checked the oil level and found correct level on dipstick. Attempted to start, no start. Towed to shop, they drained the oil and verified correct oil quantity cam out. Pulled the oil pan and found metal in the oil pan. Told I need a replacement engine. Engine has 95k miles with proper maintenance performed per the owners manual.

NHTSA ODI #11720546

Mileage unknown · Jan 9, 2026
EngineUnknown Or Other

I was driving down the freeway on cruise,when all of a sudden,the vehicle started vibrating and shaking violently.This happened in the middle of a downpour,and the tires broke loose momentarily,but I was able to gain control,and safely pull on to the shoulder.After searching the internet,this incident sounds very much like a bro…

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I was driving down the freeway on cruise,when all of a sudden,the vehicle started vibrating and shaking violently.This happened in the middle of a downpour,and the tires broke loose momentarily,but I was able to gain control,and safely pull on to the shoulder.After searching the internet,this incident sounds very much like a broken crankshaft,as described in the many,many reports of this type of failure,especialy in the 2016 model years,like mine.

NHTSA ODI #11709811

Mileage unknown · Nov 25, 2025
Engine

emission can not get a state inspection because of a bad catalytic system Nissan will not warrantee it 2016 Nissan Titan XD 67k on it 6000k to fix not right

NHTSA ODI #11701604

Mileage unknown · Oct 29, 2025
Engine

WAS DRIVING TO WORK AND ENGINE HAD HICCUP AND ALMOST SHUTOFF IN MIDDLE OF ROADWAY. WAS ABLE TO LIMP TRUCK TO MY DESTINATION. ENGINE WAS RUNNING ROUGH. NO FAULT CODES OR DASH LIGHTS TO INDICATE ANY ISSUES. TOOK TRUCK TO SHOP AND THEY COULD NOT FIGURE IT OUT. HAD SERVICE SHOP DRAIN OIL AND INSPECT OIL FILTER. METAL DEBRIS WAS FOUN…

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WAS DRIVING TO WORK AND ENGINE HAD HICCUP AND ALMOST SHUTOFF IN MIDDLE OF ROADWAY. WAS ABLE TO LIMP TRUCK TO MY DESTINATION. ENGINE WAS RUNNING ROUGH. NO FAULT CODES OR DASH LIGHTS TO INDICATE ANY ISSUES. TOOK TRUCK TO SHOP AND THEY COULD NOT FIGURE IT OUT. HAD SERVICE SHOP DRAIN OIL AND INSPECT OIL FILTER. METAL DEBRIS WAS FOUND IN OIL AND OIL FILTER. HAD ENGINE REMOVED FROM TRUCK AND FOUND 3 SPUN MAIN BEARINGS, CRANKSHAFT POSSIBLY BROKEN.

NHTSA ODI #11696279

Mileage unknown · Sep 21, 2025
Engine

Driving down the road and engine lost power and shut off. Took it to a shop and they said my crankshaft broke.

NHTSA ODI #11688740

Mileage unknown · Aug 12, 2025
Engine

There is a known issue by Nissan regarding many issues with the XD Diesel platform trucks. Mine is a castrophic engine failure at 76,237 miles. There was a recall previously on turbos for many 2016s & 2017s. One is not showing up for mine and as I bought the truck used can not confirm or deny my truck was one effected by this …

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There is a known issue by Nissan regarding many issues with the XD Diesel platform trucks. Mine is a castrophic engine failure at 76,237 miles. There was a recall previously on turbos for many 2016s & 2017s. One is not showing up for mine and as I bought the truck used can not confirm or deny my truck was one effected by this recall. I was driving and heard a light thump and had just had my tires rotated. It sounds like a tool or piece of rubber was inside the tire. I got out and made sure tires were on tight. Got back in the truck and got an engine loss of power warning and then the "oil pressure low stop vehicle" warning. I immediately pulled over and called insurance company for a tow. My truck now sits at the dealership needing a new motor and 2 turbos to the estimated cost of $39,850.

NHTSA ODI #11680093

Mileage unknown · Jun 8, 2025
Electrical SystemEngine

Dear Sir/Madam Masked Oil Pressure Warning in 2016 Nissan Titan XD (5.0L) I am writing to report a concerning and potentially dangerous defect observed in a 2016 Nissan Titan XD equipped with the 5.0L Cummins V8 diesel engine. As a Nissan Master Technician with extensive experience in vehicle diagnostics and repair, I believe …

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Dear Sir/Madam Masked Oil Pressure Warning in 2016 Nissan Titan XD (5.0L) I am writing to report a concerning and potentially dangerous defect observed in a 2016 Nissan Titan XD equipped with the 5.0L Cummins V8 diesel engine. As a Nissan Master Technician with extensive experience in vehicle diagnostics and repair, I believe this specific defect could be a contributing factor to the well-documented crankshaft breaking condition prevalent in these vehicles, which NHTSA is currently investigating. The specific issue I have identified and thoroughly documented on my own 2016 Nissan Titan XD is as follows: Observed Defect: The engine oil pressure gauge consistently reads "normal" (approximately 1/2 scale) at all times, including with the Key On, Engine Off (KOEO). Crucially, the corresponding oil pressure warning light does NOT illuminate during the normal Key On, Engine Off bulb check or at any other time, despite the engine not running. Diagnostic Findings (Summary): Preliminary diagnostics, including unplugging the oil pressure sensor, indicate a likely fault with the oil pressure sending unit itself, causing it to send a false "normal pressure" signal. This specific sensor defect fundamentally compromises the vehicle's critical oil pressure monitoring system. ( the engine is running ok, no other symptoms) Potential Safety Implications and Link to Crankshaft Failure: This defect creates an immediate and severe safety risk because it completely masks any actual low oil pressure condition that the engine may develop. Documentation: I have well-documented photographic evidence of the current occurrence described condition (gauge reading, non-illuminated warning light KOEO) which I can provide upon request to support this report. I urge the NTSB to include this specific oil pressure sensor/warning system defect in its ongoing investigation into the 2016 Nissan Titan XD 5.0L Cummins engine failures Sincerely, [XXX] Nissan Master Technician ASE-1104-7529 INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION

NHTSA ODI #11665655

Mileage unknown · May 19, 2025
Engine

My vehicle spun a bearing, or broke the crankshaft in two, there is tons of metal in my oil, oil pan, and oil filter. The shop that is diagnosing it, and quoting me a new motor, said they have replaced AT LEAST 7 titan xd Cummins motors, and every single forum and person online that owns one reports the crank shaft breaking. Ni…

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My vehicle spun a bearing, or broke the crankshaft in two, there is tons of metal in my oil, oil pan, and oil filter. The shop that is diagnosing it, and quoting me a new motor, said they have replaced AT LEAST 7 titan xd Cummins motors, and every single forum and person online that owns one reports the crank shaft breaking. Nissan or Cummins needs to be held responsible for this. And the NHTSA needs to put their foot down and actually protect American consumers. They sold these trucks for at minimum 40k and the motors all blow up around 100k miles? Absolutely disgusting that they can get away with this. What do expect in America I guess

NHTSA ODI #11661885

Mileage unknown · Apr 10, 2025
Back Over PreventionEngine

Engine made a loud popping noise, shuttered and stalled in heavy traffic, I came within inches of being rear-ended. Required a tow truck. Repair shop informed me that the crankshaft is broken and this is a common problem. Being repaired at this time, I am informed this will cost about twenty thousand dollars. Thank you Nissan!

NHTSA ODI #11653885

Official recalls

3

18V240000 · Equipment:other:labels

Apr 16, 2018

Nissan North America, Inc. (Nissan) is recalling certain 2016-2018 Nissan Titan, 2016 and 2018 Nissan Titan XD vehicles. Accessories installed on these vehicles reduced the load carrying capacity, however, a Load Carrying Capacity modification label was not installed, possibly allowing the vehicle to be overloaded. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 110, "Tire Selection and Rims."

Consequence & remedy

Consequence: An overloaded vehicle can increase the risk of a crash.

Remedy: Nissan will notify owners and provide a new modification label, with installation instructions, free of charge. The recall began on June 4, 2018. Owners may contact Nissan customer service at 1-800-867-7669.

17V268000 · Seat Belts:rear/other

Apr 24, 2017

Nissan North America, Inc. (Nissan) is recalling certain 2016-2017 Nissan Titan Crew Cab and Titan XD Crew Cab vehicles. In the event of a crash, the rear seatbelt assembly may not adequately protect the occupant's head, allowing it to contact the D-ring bolt trim cap. As such, these vehicles fail to conform to Federal Motor Vehicle Safety Standard (FMVSS) number 201, "Occupant Protection in Interior Impact."

Consequence & remedy

Consequence: If the occupant's head contacts the D-ring bolt trim cap during a crash, there is an increased risk of injury.

Remedy: Nissan will notify owners, and dealers will install energy absorbing material to the C-Pillar Finishers and replace the Seatbelt Bolt and Bolt Cap, free of charge. The recall began September 19, 2017. Owners may contact Nissan customer service at 1-800-647-7261.

16V847000 · Fuel System, Diesel:storage:tank Assembly

Nov 22, 2016

Nissan North America, Inc. (Nissan) is recalling certain model year 2016 Titan Diesel XD vehicles manufactured August 7, 2015, to September 1, 2016. The affected vehicles may not have had the temporary fuel tank breather tube cap removed during the vehicle's assembly and the fuel tank breather tube may not have been connected to the bed rail. As a result, the fuel tank may not have the proper ventilation, possibly causing the fuel gauge and the distance to empty meter to both display inaccurately.

Consequence & remedy

Consequence: If the fuel gauge reads incorrectly, the vehicle can run out of fuel without the driver being aware, increasing the risk of a crash.

Remedy: Nissan will notify owners, and dealers will inspect the fuel tank breather tube, replacing the fuel tank, fuel sending unit, and/or fuel tank breather tube, as necessary, free of charge. The recall began on December 12, 2016. Owners may contact Nissan customer service at 1-800-647-7261.

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

PE23020 · Loss Of Motive Power Due To Broken Crankshaft With No Ability To Restart.

Opened Nov 15, 2023 · Closed Jun 27, 2025

Status: closed (inferred from source dates) · Engine; Engine And Engine Cooling:engine:diesel

On November 15, 2023, the Office of Defects Investigation (ODI) opened Preliminary Evaluation PE23020 to investigate allegations of loss of motive power in model year (MY) 2016 through 2019 Nissan Titan XD trucks equipped with 5.0L Cummins diesel engines.  The complaints allege the condition was due to a failure of the engine crankshaft.  The purpose of the investigation was to understand the scope, frequency, and safety related consequence of the alleged defect. During the investigation, it was found that the subject vehicles can experience a loss of motive power due to a failure of the crankshaft main bearings which can lead to a fractured crankshaft. This resulted in a loss of motive power and an inability to restart. An analysis of all complaint sources shows many vehicles exhibit knocking, vibration, malfunction indicator lamp (MIL) warnings, and/or poor engine performance prior to a total failure.  Some consumers report driving their truck in for repairs only to be diagnosed with a failed crankshaft.  ODI has not identified any injuries or fires attributable to this failure. ODI is aware of one complaint alleging a non-injury crash involving a curb strike.  ODI is also aware of complaints of overheating starter motors and melted starter motor wiring occurring after prolonged attempts to start engines that have suffered a broken crankshaft. In its response to ODI's January 26, 2024 information request letter, Nissan provided information detailing several material and process changes involved in the production of the subject vehicle’s engine.These changes appear to coincide with incremental improvements in failure rates but there is no indication that a single factor was the primary cause of the failures. Analysis of ODI consumer complaints and manufacturer provided data found that failure rates decreased progressively for each model year. Review of failure mileage found that 50% of the failures occurred by 60,000 miles with a significant decrease in failures after 80,000 miles. Assuming average yearly mileage driven, the newest model year trucks (2019) would be near or past peak failure mileage. Given the low failure rate, the observable warnings available to the driver, and much of the fleet being past peak failure mileage, ODI is closing this Preliminary Evaluation with no further action.  The closing of the investigation does not constitute a finding by NHTSA that a defect does not exist, and NHTSA will take further action if warranted by future circumstances. To review the ODI reports cited in the Closing Resume ODI Report Identification Number document, go to NHTSA.gov.

Additional source detail variants (2)

Engine And Engine Cooling:engine:diesel

On November 15, 2023, the Office of Defects Investigation (ODI) opened Preliminary Evaluation PE23020 to investigate allegations of loss of motive power in model year (MY) 2016 through 2019 Nissan Titan XD trucks equipped with 5.0L Cummins diesel engines.  The complaints allege the condition was due to a failure of the engine crankshaft.  The purpose of the investigation was to understand the scope, frequency, and safety related consequence of the alleged defect. During the investigation, it was found that the subject vehicles can experience a loss of motive power due to a failure of the crankshaft main bearings which can lead to a fractured crankshaft. This resulted in a loss of motive power and an inability to restart. An analysis of all complaint sources shows many vehicles exhibit knocking, vibration, malfunction indicator lamp (MIL) warnings, and/or poor engine performance prior to a total failure.  Some consumers report driving their truck in for repairs only to be diagnosed with a failed crankshaft.  ODI has not identified any injuries or fires attributable to this failure. ODI is aware of one complaint alleging a non-injury crash involving a curb strike.  ODI is also aware of complaints of overheating starter motors and melted starter motor wiring occurring after prolonged attempts to start engines that have suffered a broken crankshaft. In its response to ODI's January 26, 2024 information request letter, Nissan provided information detailing several material and process changes involved in the production of the subject vehicle’s engine.These changes appear to coincide with incremental improvements in failure rates but there is no indication that a single factor was the primary cause of the failures. Analysis of ODI consumer complaints and manufacturer provided data found that failure rates decreased progressively for each model year. Review of failure mileage found that 50% of the failures occurred by 60,000 miles with a significant decrease in failures after 80,000 miles. Assuming average yearly mileage driven, the newest model year trucks (2019) would be near or past peak failure mileage. Given the low failure rate, the observable warnings available to the driver, and much of the fleet being past peak failure mileage, ODI is closing this Preliminary Evaluation with no further action.  The closing of the investigation does not constitute a finding by NHTSA that a defect does not exist, and NHTSA will take further action if warranted by future circumstances. To review the ODI reports cited in the Closing Resume ODI Report Identification Number document, go to NHTSA.gov.

Engine

On November 15, 2023, the Office of Defects Investigation (ODI) opened Preliminary Evaluation PE23020 to investigate allegations of loss of motive power in model year (MY) 2016 through 2019 Nissan Titan XD trucks equipped with 5.0L Cummins diesel engines.  The complaints allege the condition was due to a failure of the engine crankshaft.  The purpose of the investigation was to understand the scope, frequency, and safety related consequence of the alleged defect. During the investigation, it was found that the subject vehicles can experience a loss of motive power due to a failure of the crankshaft main bearings which can lead to a fractured crankshaft. This resulted in a loss of motive power and an inability to restart. An analysis of all complaint sources shows many vehicles exhibit knocking, vibration, malfunction indicator lamp (MIL) warnings, and/or poor engine performance prior to a total failure.  Some consumers report driving their truck in for repairs only to be diagnosed with a failed crankshaft.  ODI has not identified any injuries or fires attributable to this failure. ODI is aware of one complaint alleging a non-injury crash involving a curb strike.  ODI is also aware of complaints of overheating starter motors and melted starter motor wiring occurring after prolonged attempts to start engines that have suffered a broken crankshaft. In its response to ODI's January 26, 2024 information request letter, Nissan provided information detailing several material and process changes involved in the production of the subject vehicle’s engine.These changes appear to coincide with incremental improvements in failure rates but there is no indication that a single factor was the primary cause of the failures. Analysis of ODI consumer complaints and manufacturer provided data found that failure rates decreased progressively for each model year. Review of failure mileage found that 50% of the failures occurred by 60,000 miles with a significant decrease in failures after 80,000 miles. Assuming average yearly mileage driven, the newest model year trucks (2019) would be near or past peak failure mileage. Given the low failure rate, the observable warnings available to the driver, and much of the fleet being past peak failure mileage, ODI is closing this Preliminary Evaluation with no further action.  The closing of the investigation does not constitute a finding by NHTSA that a defect does not exist, and NHTSA will take further action if warranted by future circumstances. To review the ODI reports cited in the Closing Resume ODI Report Identification Number document, go to NHTSA.gov.

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.