IllustrationREAR DIFFERENTIAL MAKES A GRINDING NOISE WHEN I MAKE TURNS. DODGE ISSUED A STAR NUMBER AND FIXED IT BEFORE
2016 Dodge Challenger
Owner reports · Recalls · Investigations
Similar to other model years
Owner complaints for the 2016 Dodge Challenger do not stand out strongly from the model-year median of 45.
About this comparison →How this year compares
Owner complaints by model year
Compare all Challenger years →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
260–25K
1325–50K
350–75K
275–100K
2100–150K
1150K+
47 reports with mileage · 31 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.
- Power Train. Review the 16 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Electrical System. Review the 15 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Engine. Review the 12 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
NHTSA owner reports · September 18, 2026 snapshot.
10 crash reports2 fire reports9 injury reports
Power Train complaints
16 reportsSLOWLY PULLING OUT OF CARPORT AREA MAKING AN INCLINED RIGHT TURN I GET A DISTINCTIVE SCREECHING SOUND. SOMETHING IS SLIPPING ALMOST SOUNDS AND FEELS LIKE IM BRAKING AND HITTING THE GAS: AS IN BURNING RUBBER. JUST HAD POWERTRAIN UPDATED AND SHE STILL DOES IT. PLEASE NOTE THAT THE INCLINE IS RELATIVELY MILD, I DO NOT HAVE A SH…
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SLOWLY PULLING OUT OF CARPORT AREA MAKING AN INCLINED RIGHT TURN I GET A DISTINCTIVE SCREECHING SOUND. SOMETHING IS SLIPPING ALMOST SOUNDS AND FEELS LIKE IM BRAKING AND HITTING THE GAS: AS IN BURNING RUBBER. JUST HAD POWERTRAIN UPDATED AND SHE STILL DOES IT. PLEASE NOTE THAT THE INCLINE IS RELATIVELY MILD, I DO NOT HAVE A SHARP TURN, SO I AM NOT CRANKING MY STEERING WHEEL, I'VE TRIED TO SHIFT INTO FIRST, GO SUPER SLOW, USE TRACTION CONTROL BUTTON (WHICH INDECENTLY DOES NOT TURN ON ANYMORE AFTER POWERTRAIN RECALL UPDATE). THE MECHANICS AT TWO SEPARATE NISSANS DEALERSHIPS CANNOT FIND AN ERROR WHEN TESTING THEY CANT FIND AN ERROR OR ERROR CODE. ONE OTHER NOTE IS THAT THIS WAS A CONTNIOUS AND EMBARRASSING DAILY PROBLEM. AFTER POWERTRAIN UPDATE IT IS INCONSISTENT BUT 80% OF THE TIME SHE SQUEALS) ONCE AGAIN, I BARLEY TOUCH GAS AM NOT YANKING WHEEL. IT HAPPENS FROM A DEAD STOP TO ME TURNING OR ME COASTING WITHOUT STOPPING. HELL, IVE EVEN TRIED TO GUN IT (IT WAS WORSE) HERE TIRES ARE IN VERY GOOD CONDITION AND ARE INFLATED PROPERLY DON'T KNOW IF THIS NEXT PIECE OF INFO WILL HELP?: SHE SEEMS TO HAVE A SLIGHT LAG IN IN HER ABILITY TO ACCELERATE WHEN I FLOOR THE GAS PEDDLE TO SPEED UP TO PASS SOMEONE OR JUMP ON FREEWAY. SHE DIDN'T DO THAT TO START WITH, AFTER.POWERTRAIN UPDATE RECALL, SHE IS A BIT SMOOTHER. I THANK YOU FOR YOU TIME AGAIN I LOVE MY CAR (BARLEY OVER 30K MILES ). I AND JUST A SIDE NOTE: I DO LET MY HER WARM UP, UNTIL SHE IS DROPS TO A PERFECT 1R :) FOR DATE IT HAPPENED I'M PUTTING THE TODAY. ITS BEEN HAPPENING FOR 1.5 TO TWO YEARS, SLOWLY INCREASED FROM OCCASIONALLY TO CONSTANTLY . AND ONCE AGAIN IT IS AFTER THE POWER TRAIN UPDATE, IT STOPPED DOING IT EVERY TIME BUT IT IS STILL FREQUENT. SHE DOES IT IF I'N TURNING SLOWLY UP OTHER INCLINES. AGAIN IM PUTTING TODAYS DATE SO YOU KNOW IT IS A PRESENT ISSUE. THANK YOU .
CAR STICKS IN GEAR WHEN PARKED OR DRIVING. SNYCHS REPLACED AT 41K NOW AT 49K CLUTCH PLATE NOW NEEDS REPLACING. THIS VEHICLE HAS ALMOST CAUSED ACCIDENTS AS I COULD NOT GET IT IN/ OUT OF GEAR WHILE DRIVING.
TL* THE CONTACT OWNS A 2016 DODGE CHALLENGER. THE CONTACT STATED THAT THE AIR BAG WARNING INDICATOR ILLUMINATED. ALSO, WHENEVER THE BRAKE PEDAL WAS DEPRESSED, THE BRAKES MADE A SQUEAKING NOISE AS IF THEY WERE PREMATURELY WEARING. THE CONTACT STATED THAT THE BRAKES FAILED TO STOP THE VEHICLE IN A TIMELY MANNER. THE VEHICLE ALSO M…
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TL* THE CONTACT OWNS A 2016 DODGE CHALLENGER. THE CONTACT STATED THAT THE AIR BAG WARNING INDICATOR ILLUMINATED. ALSO, WHENEVER THE BRAKE PEDAL WAS DEPRESSED, THE BRAKES MADE A SQUEAKING NOISE AS IF THEY WERE PREMATURELY WEARING. THE CONTACT STATED THAT THE BRAKES FAILED TO STOP THE VEHICLE IN A TIMELY MANNER. THE VEHICLE ALSO MADE A CLUNKING NOISE AS IF METAL WERE TOUCHING WHENEVER THE GEARS WERE SHIFTED FROM PARK TO DRIVE AND VICE VERSA, AS WELL AS WHENEVER THE CONTACT DROVE DOWNHILL. THE CONTACT TOOK THE VEHICLE TO POWAY CHRYSLER JEEP DODGE RAM (13811 POWAY ROAD, POWAY, CA 92064; 858-218-2213) WHERE IT WAS DIAGNOSED THAT THE BRAKE PADS NEEDED TO BE REPLACED. THE MANUFACTURER WAS MADE AWARE OF THE FAILURE AND OPENED CASE NUMBERS: 30285247 AND 31041577. THE MANUFACTURER ALSO SENT AN INVESTIGATOR TO VIEW THE BRAKES. THE INVESTIGATOR STATED THAT THE BRAKES WERE NOT IN NEED OF REPAIR. THE CONTACT RETURNED THE VEHICLE TO THE POWAY DODGE REGARDING THE TRANSMISSION, BUT THEY WERE UNABLE TO DUPLICATE THE FAILURE. THE MANUFACTURER WAS MADE AWARE OF THE TRANSMISSION FAILURE AND OPENED CASE NUMBERS: 32657810 AND 32920890. THE FAILURE WAS NOT REPAIRED. THE CONTACT TOOK THE VEHICLE TO THE SAME POWAY DODGE DEALER REGARDING THE AIR BAG WARNING SENSOR, BUT THEY DID NOT DIAGNOSE THE FAILURE. THE BRAKE PADS AND ROTORS WERE REPLACED TWICE, BUT THE FAILURE RECURRED. THE VEHICLE WAS NOT REPAIRED FOR THE TRANSMISSION AND THE AIR BAG WARNING INDICATOR FAILURES. THE APPROXIMATE FAILURE MILEAGE WAS 10,000.
TL* THE CONTACT OWNS A 2016 DODGE CHALLENGER. THE CONTACT STATED THAT WHILE DRIVING AT VARIOUS SPEEDS AND USING THE PADDLE SHIFTER TO SHIFT TO AN UP GEAR, THE VEHICLE WOULD DOWN SHIFT INSTEAD. THE CONTACT STATED THAT THE WHEN THE FAILURE FIRST OCCURRED THE VEHICLE WAS TAKEN TO BOTH AN INDEPENDENT MECHANIC AND WHITTEN BROTHERS OF…
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TL* THE CONTACT OWNS A 2016 DODGE CHALLENGER. THE CONTACT STATED THAT WHILE DRIVING AT VARIOUS SPEEDS AND USING THE PADDLE SHIFTER TO SHIFT TO AN UP GEAR, THE VEHICLE WOULD DOWN SHIFT INSTEAD. THE CONTACT STATED THAT THE WHEN THE FAILURE FIRST OCCURRED THE VEHICLE WAS TAKEN TO BOTH AN INDEPENDENT MECHANIC AND WHITTEN BROTHERS OF RICHMOND LOCATED AT 10701 MIDLOTHIAN TURNPIKE #100, RICHMOND, VA 23235, PHONE NUMBER: (804) 378-0707, WHERE THE FAILURE COULD NOT BE DUPLICATED. THE CONTACT STATED THAT HE THEN PURCHASED A DASH-CAM AND UPON RECORDING THE FAILURE, THE VEHICLE WAS TAKEN BACK TO THE LOCAL DEALER WHITTEN BROTHERS OF RICHMOND 10701 MIDLOTHIAN TURNPIKE #100, RICHMOND, VA 23235 (804) 378-0707, WHERE BOTH PADDLE SHIFTER BUTTONS WERE REPLACED. THE CONTACT STATED THAT THE FAILURE HAD RECURRED SEVERAL TIMES. THE MANUFACTURER WAS MADE AWARE OF THE FAILURE. THE FAILURE MILEAGE WAS APPROXIMATELY 2,007.
DRIVELINE CLUNK NOISE IN REAR OF VEHICLE WHEN COMING TO A STOP BETWEEN 3 TO 6 MPH DOWNSHIFTING. THIS HAPPENS NO MATTER WHAT THE ROAD SURFACE YOUR ON. THIS IS A NEW VEHICLE WITH LESS THAN 500 MILES, AFTER I WENT TO MY COUNTY PROBATE OFFICE TO GET MY LICENCE TAG, THIS OCCURRED EVERY TIME I CAME TO A FULL STOP AT A SIGN, LIGHT OR …
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DRIVELINE CLUNK NOISE IN REAR OF VEHICLE WHEN COMING TO A STOP BETWEEN 3 TO 6 MPH DOWNSHIFTING. THIS HAPPENS NO MATTER WHAT THE ROAD SURFACE YOUR ON. THIS IS A NEW VEHICLE WITH LESS THAN 500 MILES, AFTER I WENT TO MY COUNTY PROBATE OFFICE TO GET MY LICENCE TAG, THIS OCCURRED EVERY TIME I CAME TO A FULL STOP AT A SIGN, LIGHT OR BEHIND A VEHICLE IN FRONT OF ME. TOOK VEHICLE TO DEALERSHIP, SERVICE MANAGER CAME OUT TO SEE IF ANYTHING WAS LOOSE IN TRUNK, SPARE TIRE,ETC. NO PROBLEM FOUND, I WAS TOLD TO BRING CAR BACK MONDAY MORNING FOR FURTHER DIAGNOSIS WHERE TECHS CAN FIND PROBLEM. I HAVE HEARD OTHERS COMPLAIN OF THIS ISSUE WITH THEIR CHALLENGERS BUT NO AVAIL, OR THEY WOULD TELL THE OWNERS THAT THIS WAS NORMAL. NO THIS IS NOT NORMAL IN THE DRIVELINE, PLEASE INVESTIGATE THIS ISSUE SO IT CAN BE RESOLVED WITH CHRYSLER WETHER A RECALL OR TSB NEEDS TO BE ENFORCED TO SOLVE THIS DRIVELINE ISSUE. THANKS FOR YOUR TIME IN THIS MATTER.
Official recalls
118V332000 · Electrical System:software; Electrical System:wiring; Vehicle Speed Control:cruise Control
May 17, 2018
Chrysler (FCA US LLC) is recalling certain 2014-2018 Dodge Journey, Charger and Durango, RAM 2500, 3500, 3500 Cab Chassis (more than 10,000lb), 4500 Cab Chassis and 5500 Cab Chassis, Jeep Cherokee and Grand Cherokee and Chrysler 300, 2014-2019 RAM 1500, 2015-2018 Dodge Challenger, 2015-2017 Chrysler 200, 2016-2018 RAM 3500 Cab Chassis (less than 10,000 lb), 2017-2018 Chrysler Pacifica and 2018 Jeep Wrangler vehicles. These vehicles are being recalled to address a defect that could prevent the cruise control system from disengaging. If, when using cruise control, there is a short circuit within the vehicle's wiring, the driver may not be able to shut off the cruise control either by depressing the brake pedal or manually turning the system off once it has been engaged, resulting in either the vehicle maintaining its current speed or possibly accelerating.
Consequence & remedy
Consequence: If the vehicle maintains its speed or accelerates despite attempts to deactivate the cruise control, there would be an increased risk of a crash.
Remedy: Chrysler will notify owners, and dealers will inspect the software, and perform a software flash on the engine or powertrain control module, free of charge. The recall began June 4, 2018. Owners may contact Chrysler customer service at 1-800-853-1403. Note: Owners are advised to stop using cruise control until the software update has been performed. In the event that cruise control cannot be disengaged while driving, owners should firmly and steadily apply the brakes and shift the transmission to neutral, placing the vehicle in park once it has stopped.
Additional source detail variants (3)
Electrical System:software
Chrysler (FCA US LLC) is recalling certain 2014-2018 Dodge Journey, Charger and Durango, RAM 2500, 3500, 3500 Cab Chassis (more than 10,000lb), 4500 Cab Chassis and 5500 Cab Chassis, Jeep Cherokee and Grand Cherokee and Chrysler 300, 2014-2019 RAM 1500, 2015-2018 Dodge Challenger, 2015-2017 Chrysler 200, 2016-2018 RAM 3500 Cab Chassis (less than 10,000 lb), 2017-2018 Chrysler Pacifica and 2018 Jeep Wrangler vehicles. These vehicles are being recalled to address a defect that could prevent the cruise control system from disengaging. If, when using cruise control, there is a short circuit within the vehicle's wiring, the driver may not be able to shut off the cruise control either by depressing the brake pedal or manually turning the system off once it has been engaged, resulting in either the vehicle maintaining its current speed or possibly accelerating.
Consequence: If the vehicle maintains its speed or accelerates despite attempts to deactivate the cruise control, there would be an increased risk of a crash.
Remedy: Chrysler will notify owners, and dealers will inspect the software, and perform a software flash on the engine or powertrain control module, free of charge. The recall began June 4, 2018. Owners may contact Chrysler customer service at 1-800-853-1403. Note: Owners are advised to stop using cruise control until the software update has been performed. In the event that cruise control cannot be disengaged while driving, owners should firmly and steadily apply the brakes and shift the transmission to neutral, placing the vehicle in park once it has stopped.
Vehicle Speed Control:cruise Control
Chrysler (FCA US LLC) is recalling certain 2014-2018 Dodge Journey, Charger and Durango, RAM 2500, 3500, 3500 Cab Chassis (more than 10,000lb), 4500 Cab Chassis and 5500 Cab Chassis, Jeep Cherokee and Grand Cherokee and Chrysler 300, 2014-2019 RAM 1500, 2015-2018 Dodge Challenger, 2015-2017 Chrysler 200, 2016-2018 RAM 3500 Cab Chassis (less than 10,000 lb), 2017-2018 Chrysler Pacifica and 2018 Jeep Wrangler vehicles. These vehicles are being recalled to address a defect that could prevent the cruise control system from disengaging. If, when using cruise control, there is a short circuit within the vehicle's wiring, the driver may not be able to shut off the cruise control either by depressing the brake pedal or manually turning the system off once it has been engaged, resulting in either the vehicle maintaining its current speed or possibly accelerating.
Consequence: If the vehicle maintains its speed or accelerates despite attempts to deactivate the cruise control, there would be an increased risk of a crash.
Remedy: Chrysler will notify owners, and dealers will inspect the software, and perform a software flash on the engine or powertrain control module, free of charge. The recall began June 4, 2018. Owners may contact Chrysler customer service at 1-800-853-1403. Note: Owners are advised to stop using cruise control until the software update has been performed. In the event that cruise control cannot be disengaged while driving, owners should firmly and steadily apply the brakes and shift the transmission to neutral, placing the vehicle in park once it has stopped.
Electrical System:wiring
Chrysler (FCA US LLC) is recalling certain 2014-2018 Dodge Journey, Charger and Durango, RAM 2500, 3500, 3500 Cab Chassis (more than 10,000lb), 4500 Cab Chassis and 5500 Cab Chassis, Jeep Cherokee and Grand Cherokee and Chrysler 300, 2014-2019 RAM 1500, 2015-2018 Dodge Challenger, 2015-2017 Chrysler 200, 2016-2018 RAM 3500 Cab Chassis (less than 10,000 lb), 2017-2018 Chrysler Pacifica and 2018 Jeep Wrangler vehicles. These vehicles are being recalled to address a defect that could prevent the cruise control system from disengaging. If, when using cruise control, there is a short circuit within the vehicle's wiring, the driver may not be able to shut off the cruise control either by depressing the brake pedal or manually turning the system off once it has been engaged, resulting in either the vehicle maintaining its current speed or possibly accelerating.
Consequence: If the vehicle maintains its speed or accelerates despite attempts to deactivate the cruise control, there would be an increased risk of a crash.
Remedy: Chrysler will notify owners, and dealers will inspect the software, and perform a software flash on the engine or powertrain control module, free of charge. The recall began June 4, 2018. Owners may contact Chrysler customer service at 1-800-853-1403. Note: Owners are advised to stop using cruise control until the software update has been performed. In the event that cruise control cannot be disengaged while driving, owners should firmly and steadily apply the brakes and shift the transmission to neutral, placing the vehicle in park once it has stopped.
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
1EA21002 · 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.