IllustrationTail lights are very inconsistent of working or not working. Sometimes they work but most times they don't.
2015 GMC Yukon Xl
Owner reports · Recalls · Investigations
More warning signs than most Yukon Xl years
Owner complaints for the 2015 GMC Yukon Xl are substantially higher than the model-year median of 68.
About this comparison →How this year compares
Owner complaints by model year
Compare all Yukon Xl 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
120–25K
3025–50K
7150–75K
4775–100K
33100–150K
7150K+
200 reports with mileage · 106 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.
- Exterior Lighting. Review the 140 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Service Brakes. Review the 62 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Electrical System. Review the 58 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
NHTSA owner reports · September 18, 2026 snapshot.
6 crash reports3 fire reports2 injury reports
What owners actually said
306 reportsTrailer brake service malfunction
This vehicle was purchased on 7/05/2019 with miles 52,000 and the TRAILER BREAKE SYSTEM has gone bad 2 times already and I haven’t never used the trailer hook for anything is just so expensive to fixed it and goes bad again and all part we’re purchased from the dealership even the dealer said is a manufacturer error and this wil…
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This vehicle was purchased on 7/05/2019 with miles 52,000 and the TRAILER BREAKE SYSTEM has gone bad 2 times already and I haven’t never used the trailer hook for anything is just so expensive to fixed it and goes bad again and all part we’re purchased from the dealership even the dealer said is a manufacturer error and this will keep happening because is manufacturer error was not designed correctly as a consumer I feel that I shouldn’t be paying for their mistake GMC should do recall and get this issue fixed as soon as possible and fixed it 2 times I have been at the dealership to get this issue fixed and I’ll probably be back again to get fixed and like mentioned is not cheap to fixed please do something about this matter I’ll gladly appreciate
My vehicle Has a Service Trailer Brake System notification in my dash that dings as well. It does it on cold mornings with no trailer attached. I don’t trailer often.
Trailer brake system keeps beeping and nothing is wrong, had it checked out several times.
Trailer assist error. Brakes not working. Ac compressors been replaced and the fan runs after the vehicles off and ac only blows warm air
Both tail lights work intermittently. Short in wiring ?
My Wife was driving at a low speed completing a right hand turn through an intersection and as she completed the turn the vehicle completely lost all steering. The vehicle ran up onto a curb but she was able to stop before she hit a poll. The vehicle was towed home and I found that there was no power to the steering wheel contro…
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My Wife was driving at a low speed completing a right hand turn through an intersection and as she completed the turn the vehicle completely lost all steering. The vehicle ran up onto a curb but she was able to stop before she hit a poll. The vehicle was towed home and I found that there was no power to the steering wheel controls, the horn didn't work and there were Electronic Steering warnings. I also found that the steering wheel could spin freely like a top without any movement of the wheels. Upon examination in the engine compartment I found that the bottom of the steering shaft was completely disconnected and the single bolt that holds the 2 pieces together was missing. I took the vehicle to the local GMC dealership and they conformed that the bolt was missing and the shafts came apart which lead to the steering failure. The free movement of the steering wheel caused the internal malfunction of the steering wheel electronics. Prior to the steering failure there was no indications of any steering issues. The steering warning lights didn't come on until the steering failure. My Wife and children were about to get on the freeway when the failure occurred and could have led to a fatal accident if this failure occurred while she was driving on the freeway. I contacted GM and opened a case but was informed that they would not provide any assistance with the repair which is about $2900. I don't understand how GM would design a steering shaft that has a single point failure that could lead to a catastrophic failure. The vehicle has 120K miles and has never been in any accidents. I expect a basic safety feature such as the steering to never fail during operation. I will never purchase another GM vehicle and will tell as many people as I can about the potential failure. GM case# [XXX]. INFORMATION Redacted PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6).
I received a letter from GMC dated December 2019 warning of brake lights intermittenly not illuminating. I have periodically checked the lights for failure over the last 3 years. On September 8, 2022, a motorist pulled beside me and informed me that my brake lights were not working. I confirmed that the lights were not working a…
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I received a letter from GMC dated December 2019 warning of brake lights intermittenly not illuminating. I have periodically checked the lights for failure over the last 3 years. On September 8, 2022, a motorist pulled beside me and informed me that my brake lights were not working. I confirmed that the lights were not working and called GMC regarding the letter I had received in 2019 and was told that a recall had not been issued and that my vehicle was outside the 6 year eligibility period. This defect is Extremely Dangerous to myself and others due to the inherent unpredicability and unreliabilty of an important safety necessity, i.e., knowing that others will see that I am stopping/slowing down. I believe that due to the intermittent nature of the failure of a highly necessary safety feature, GMC should issue a recall to repair at no cost ALL vehicles.
My "Service Trailer Brake System" messages comes on periodically for days at a time with and without my trailer. The loud chime rings consistently for the duration of the drive. It makes driving unbearable. When connecting my trailer to it, the brakes do not seem to function correctly when towing. This is very dangerous. I fo…
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My "Service Trailer Brake System" messages comes on periodically for days at a time with and without my trailer. The loud chime rings consistently for the duration of the drive. It makes driving unbearable. When connecting my trailer to it, the brakes do not seem to function correctly when towing. This is very dangerous. I found out that a lot of my fellow GMC SUV drivers have the same problem.
Official recalls
217V437000 · Air Bags:frontal; Air Bags:frontal:sensor/control MODULE-INACTIVE ; Seat Belts:pretensioner
Jul 10, 2017
General Motors LLC (GM) is recalling certain model year 2014-2016 Buick Lacrosse and Chevrolet Spark EV, Caprice PPV and SS vehicles, 2014-2017 Buick Encore and Chevrolet Corvette, Silverado 1500 and GMC Sierra 1500 vehicles, 2015-2016 Cadillac Escalade and Escalade ESV, Chevrolet Tahoe, Trax, Suburban and Silverado 2500 and 3500 and GMC Yukon and Yukon XL vehicles, and 2015-2017 GMC Sierra HD 2500 and 3500 vehicles. While being previously remedied for recall 16V-651, the affected vehicles may not have received the complete software update necessary to remedy the recall condition. Without the update, certain driving conditions may cause the air bag sensing and diagnostic module (SDM) software to activate a diagnostic test. During this test, deployment of the frontal air bags and the seat belt pretensioners would not occur in the event of a crash.
Consequence & remedy
Consequence: A failure of the front air bags or seat belt pretensioners to deploy in the event of a crash necessitating deployment increases the risk of injury to the driver and front passenger.
Remedy: GM will notify owners, and dealers will reflash the SDM software. Vehicles that have had a previous air bag deployment will have the SDM replaced. These repairs will be performed free of charge. The recall began on August 4, 2017. Owners may contact Buick customer service at 1-800-521-7300, Cadillac customer service at 1-800-458-8006, Chevrolet customer service at 1-800-222-1020, or GMC customer service at 1-800-462-8782. GM's number for this recall is 17287.
Additional source detail variants (3)
Seat Belts:pretensioner
General Motors LLC (GM) is recalling certain model year 2014-2016 Buick Lacrosse and Chevrolet Spark EV, Caprice PPV and SS vehicles, 2014-2017 Buick Encore and Chevrolet Corvette, Silverado 1500 and GMC Sierra 1500 vehicles, 2015-2016 Cadillac Escalade and Escalade ESV, Chevrolet Tahoe, Trax, Suburban and Silverado 2500 and 3500 and GMC Yukon and Yukon XL vehicles, and 2015-2017 GMC Sierra HD 2500 and 3500 vehicles. While being previously remedied for recall 16V-651, the affected vehicles may not have received the complete software update necessary to remedy the recall condition. Without the update, certain driving conditions may cause the air bag sensing and diagnostic module (SDM) software to activate a diagnostic test. During this test, deployment of the frontal air bags and the seat belt pretensioners would not occur in the event of a crash.
Consequence: A failure of the front air bags or seat belt pretensioners to deploy in the event of a crash necessitating deployment increases the risk of injury to the driver and front passenger.
Remedy: GM will notify owners, and dealers will reflash the SDM software. Vehicles that have had a previous air bag deployment will have the SDM replaced. These repairs will be performed free of charge. The recall began on August 4, 2017. Owners may contact Buick customer service at 1-800-521-7300, Cadillac customer service at 1-800-458-8006, Chevrolet customer service at 1-800-222-1020, or GMC customer service at 1-800-462-8782. GM's number for this recall is 17287.
Air Bags:frontal:sensor/control MODULE-INACTIVE
General Motors LLC (GM) is recalling certain model year 2014-2016 Buick Lacrosse and Chevrolet Spark EV, Caprice PPV and SS vehicles, 2014-2017 Buick Encore and Chevrolet Corvette, Silverado 1500 and GMC Sierra 1500 vehicles, 2015-2016 Cadillac Escalade and Escalade ESV, Chevrolet Tahoe, Trax, Suburban and Silverado 2500 and 3500 and GMC Yukon and Yukon XL vehicles, and 2015-2017 GMC Sierra HD 2500 and 3500 vehicles. While being previously remedied for recall 16V-651, the affected vehicles may not have received the complete software update necessary to remedy the recall condition. Without the update, certain driving conditions may cause the air bag sensing and diagnostic module (SDM) software to activate a diagnostic test. During this test, deployment of the frontal air bags and the seat belt pretensioners would not occur in the event of a crash.
Consequence: A failure of the front air bags or seat belt pretensioners to deploy in the event of a crash necessitating deployment increases the risk of injury to the driver and front passenger.
Remedy: GM will notify owners, and dealers will reflash the SDM software. Vehicles that have had a previous air bag deployment will have the SDM replaced. These repairs will be performed free of charge. The recall began on August 4, 2017. Owners may contact Buick customer service at 1-800-521-7300, Cadillac customer service at 1-800-458-8006, Chevrolet customer service at 1-800-222-1020, or GMC customer service at 1-800-462-8782. GM's number for this recall is 17287.
Air Bags:frontal
General Motors LLC (GM) is recalling certain model year 2014-2016 Buick Lacrosse and Chevrolet Spark EV, Caprice PPV and SS vehicles, 2014-2017 Buick Encore and Chevrolet Corvette, Silverado 1500 and GMC Sierra 1500 vehicles, 2015-2016 Cadillac Escalade and Escalade ESV, Chevrolet Tahoe, Trax, Suburban and Silverado 2500 and 3500 and GMC Yukon and Yukon XL vehicles, and 2015-2017 GMC Sierra HD 2500 and 3500 vehicles. While being previously remedied for recall 16V-651, the affected vehicles may not have received the complete software update necessary to remedy the recall condition. Without the update, certain driving conditions may cause the air bag sensing and diagnostic module (SDM) software to activate a diagnostic test. During this test, deployment of the frontal air bags and the seat belt pretensioners would not occur in the event of a crash.
Consequence: A failure of the front air bags or seat belt pretensioners to deploy in the event of a crash necessitating deployment increases the risk of injury to the driver and front passenger.
Remedy: GM will notify owners, and dealers will reflash the SDM software. Vehicles that have had a previous air bag deployment will have the SDM replaced. These repairs will be performed free of charge. The recall began on August 4, 2017. Owners may contact Buick customer service at 1-800-521-7300, Cadillac customer service at 1-800-458-8006, Chevrolet customer service at 1-800-222-1020, or GMC customer service at 1-800-462-8782. GM's number for this recall is 17287.
16V651000 · Air Bags:frontal; Air Bags:frontal:sensor/control MODULE-INACTIVE ; Seat Belts:pretensioner
Sep 8, 2016
General Motors LLC (GM) is recalling certain model year 2015-2017 Chevrolet Silverado 2500 HD, 3500 HD, Tahoe, Suburban, GMC Sierra 2500 HD and 3500 HD, GMC Yukon, GMC Yukon XL, Cadillac Escalade and Cadillac Escalade ESV vehicles and 2014-2017 Chevrolet Corvette, Silverado 1500, Trax, Caprice Police Pursuit Vehicle, GMC Sierra 1500, Buick Encore, and 2014-2016 Buick Lacrosse, Chevrolet Spark EV and SS vehicles. In the affected vehicles, certain driving conditions may cause the air bag sensing and diagnostic module (SDM) software to activate a diagnostic test. During this test, deployment of the frontal air bags and the seat belt pretensioners would not occur in the event of a crash.
Consequence & remedy
Consequence: A failure of the front air bags or seat belt pretensioners to deploy in the event of a crash necessitating deployment increases the risk of injury to the driver and front passenger.
Remedy: GM will notify owners, and dealers will reflash the SDM software. Vehicles that have had a previous air bag deployment will have the SDM replaced. These repairs will be performed free of charge. The recall began on October 13, 2016. Owners may contact Buick customer service at 1-800-521-7300, Cadillac customer service at 1-800-458-8006, Chevrolet customer service at 1-800-222-1020, or GMC customer service at 1-800-462-8782. GM's number for this recall is 16007.
Additional source detail variants (3)
Seat Belts:pretensioner
General Motors LLC (GM) is recalling certain model year 2015-2017 Chevrolet Silverado 2500 HD, 3500 HD, Tahoe, Suburban, GMC Sierra 2500 HD and 3500 HD, GMC Yukon, GMC Yukon XL, Cadillac Escalade and Cadillac Escalade ESV vehicles and 2014-2017 Chevrolet Corvette, Silverado 1500, Trax, Caprice Police Pursuit Vehicle, GMC Sierra 1500, Buick Encore, and 2014-2016 Buick Lacrosse, Chevrolet Spark EV and SS vehicles. In the affected vehicles, certain driving conditions may cause the air bag sensing and diagnostic module (SDM) software to activate a diagnostic test. During this test, deployment of the frontal air bags and the seat belt pretensioners would not occur in the event of a crash.
Consequence: A failure of the front air bags or seat belt pretensioners to deploy in the event of a crash necessitating deployment increases the risk of injury to the driver and front passenger.
Remedy: GM will notify owners, and dealers will reflash the SDM software. Vehicles that have had a previous air bag deployment will have the SDM replaced. These repairs will be performed free of charge. The recall began on October 13, 2016. Owners may contact Buick customer service at 1-800-521-7300, Cadillac customer service at 1-800-458-8006, Chevrolet customer service at 1-800-222-1020, or GMC customer service at 1-800-462-8782. GM's number for this recall is 16007.
Air Bags:frontal:sensor/control MODULE-INACTIVE
General Motors LLC (GM) is recalling certain model year 2015-2017 Chevrolet Silverado 2500 HD, 3500 HD, Tahoe, Suburban, GMC Sierra 2500 HD and 3500 HD, GMC Yukon, GMC Yukon XL, Cadillac Escalade and Cadillac Escalade ESV vehicles and 2014-2017 Chevrolet Corvette, Silverado 1500, Trax, Caprice Police Pursuit Vehicle, GMC Sierra 1500, Buick Encore, and 2014-2016 Buick Lacrosse, Chevrolet Spark EV and SS vehicles. In the affected vehicles, certain driving conditions may cause the air bag sensing and diagnostic module (SDM) software to activate a diagnostic test. During this test, deployment of the frontal air bags and the seat belt pretensioners would not occur in the event of a crash.
Consequence: A failure of the front air bags or seat belt pretensioners to deploy in the event of a crash necessitating deployment increases the risk of injury to the driver and front passenger.
Remedy: GM will notify owners, and dealers will reflash the SDM software. Vehicles that have had a previous air bag deployment will have the SDM replaced. These repairs will be performed free of charge. The recall began on October 13, 2016. Owners may contact Buick customer service at 1-800-521-7300, Cadillac customer service at 1-800-458-8006, Chevrolet customer service at 1-800-222-1020, or GMC customer service at 1-800-462-8782. GM's number for this recall is 16007.
Air Bags:frontal
General Motors LLC (GM) is recalling certain model year 2015-2017 Chevrolet Silverado 2500 HD, 3500 HD, Tahoe, Suburban, GMC Sierra 2500 HD and 3500 HD, GMC Yukon, GMC Yukon XL, Cadillac Escalade and Cadillac Escalade ESV vehicles and 2014-2017 Chevrolet Corvette, Silverado 1500, Trax, Caprice Police Pursuit Vehicle, GMC Sierra 1500, Buick Encore, and 2014-2016 Buick Lacrosse, Chevrolet Spark EV and SS vehicles. In the affected vehicles, certain driving conditions may cause the air bag sensing and diagnostic module (SDM) software to activate a diagnostic test. During this test, deployment of the frontal air bags and the seat belt pretensioners would not occur in the event of a crash.
Consequence: A failure of the front air bags or seat belt pretensioners to deploy in the event of a crash necessitating deployment increases the risk of injury to the driver and front passenger.
Remedy: GM will notify owners, and dealers will reflash the SDM software. Vehicles that have had a previous air bag deployment will have the SDM replaced. These repairs will be performed free of charge. The recall began on October 13, 2016. Owners may contact Buick customer service at 1-800-521-7300, Cadillac customer service at 1-800-458-8006, Chevrolet customer service at 1-800-222-1020, or GMC customer service at 1-800-462-8782. GM's number for this recall is 16007.
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
1PE18012 · Brake Vacuum Pump Failure
Opened Nov 20, 2018 · Closed Apr 10, 2022
Status: closed (inferred from source dates) · Service Brakes; Service Brakes, Hydraulic; Service Brakes, Hydraulic:power Assist:vacuum
On November 20, 2018, the Office of Defects Investigations (ODI) opened PE18-012 to investigate instances of sudden onset of a hard brake pedal that could result in extended stopping distance due to an issue with the brake assist vacuum pump in model year (MY) 2014 through 2016 GMC Sierra 1500 and Chevrolet Silverado 1500 series pickup trucks and MY 2015 through 2016 Cadillac Escalade, Chevrolet Suburban, Chevrolet Tahoe, and GMC Yukon SUVs.If the brake assist vacuum pump fails to operate as intended, the amount of brake power assist supplied to the driver can be significantly reduced, extending the subject vehicle stopping distance. GM stated that the root cause of pump failures was due to foreign debris such as oil sludge in the engine oil. GM stated that this debris can become trapped by the oil inlet filter screen. Under normal operation, this screen allows a small amount of oil into the brake vacuum pump. The foreign debris can, over time, clog the pump which can cause a loss of lubrication and a reduction in the amount of vacuum produced leading to a hard pedal and extended stopping distance.On December 13, 2018, GM issued a Special Coverage (N182202780) for the brake vacuum pump issue in MY 2014-2017 trucks and 2015-2017 SUVs on the K2XX platform for 6 years or 72,000 miles. Special Coverage repair includes the replacement of the vacuum pump and vacuum pump belt. Consumers received notification of the coverage via mail. On September 6, 2019, GM notified NHTSA that it was conducting safety recall 19V-645 which reprograms the electronic brake control module (EBCM) and included approximately 3.5 million trucks and SUVs. In October 2019, GM extended the terms of special coverage N182202780 to 10 years or 150,000 miles as well as now including the entire scope of recall 19V-645. In October 2020, GM expanded the scope of coverage N182202780 to include the MY 2018 Escalade and 2019 Tahoe.The remedy implemented in GM recall 19V-645 appears to be sufficient in addressing the safety-related concerns of this issue. Loss of vacuum assist now occurs at a progressive rate as well as there being a more timely warning of a brake problem to the driver through the driver information center (DIC). In view of the recall action and revision to the special coverage, this Preliminary Evaluation is closed. The agency reserves the right to take additional action if warranted by new circumstances. The ODI reports cited above are available for review online at NHTSA.gov under the identification numbers in the attached document.
Additional source detail variants (3)
Service Brakes
On November 20, 2018, the Office of Defects Investigations (ODI) opened PE18-012 to investigate instances of sudden onset of a hard brake pedal that could result in extended stopping distance due to an issue with the brake assist vacuum pump in model year (MY) 2014 through 2016 GMC Sierra 1500 and Chevrolet Silverado 1500 series pickup trucks and MY 2015 through 2016 Cadillac Escalade, Chevrolet Suburban, Chevrolet Tahoe, and GMC Yukon SUVs.If the brake assist vacuum pump fails to operate as intended, the amount of brake power assist supplied to the driver can be significantly reduced, extending the subject vehicle stopping distance. GM stated that the root cause of pump failures was due to foreign debris such as oil sludge in the engine oil. GM stated that this debris can become trapped by the oil inlet filter screen. Under normal operation, this screen allows a small amount of oil into the brake vacuum pump. The foreign debris can, over time, clog the pump which can cause a loss of lubrication and a reduction in the amount of vacuum produced leading to a hard pedal and extended stopping distance.On December 13, 2018, GM issued a Special Coverage (N182202780) for the brake vacuum pump issue in MY 2014-2017 trucks and 2015-2017 SUVs on the K2XX platform for 6 years or 72,000 miles. Special Coverage repair includes the replacement of the vacuum pump and vacuum pump belt. Consumers received notification of the coverage via mail. On September 6, 2019, GM notified NHTSA that it was conducting safety recall 19V-645 which reprograms the electronic brake control module (EBCM) and included approximately 3.5 million trucks and SUVs. In October 2019, GM extended the terms of special coverage N182202780 to 10 years or 150,000 miles as well as now including the entire scope of recall 19V-645. In October 2020, GM expanded the scope of coverage N182202780 to include the MY 2018 Escalade and 2019 Tahoe.The remedy implemented in GM recall 19V-645 appears to be sufficient in addressing the safety-related concerns of this issue. Loss of vacuum assist now occurs at a progressive rate as well as there being a more timely warning of a brake problem to the driver through the driver information center (DIC). In view of the recall action and revision to the special coverage, this Preliminary Evaluation is closed. The agency reserves the right to take additional action if warranted by new circumstances. The ODI reports cited above are available for review online at NHTSA.gov under the identification numbers in the attached document.
Service Brakes, Hydraulic
On November 20, 2018, the Office of Defects Investigations (ODI) opened PE18-012 to investigate instances of sudden onset of a hard brake pedal that could result in extended stopping distance due to an issue with the brake assist vacuum pump in model year (MY) 2014 through 2016 GMC Sierra 1500 and Chevrolet Silverado 1500 series pickup trucks and MY 2015 through 2016 Cadillac Escalade, Chevrolet Suburban, Chevrolet Tahoe, and GMC Yukon SUVs.If the brake assist vacuum pump fails to operate as intended, the amount of brake power assist supplied to the driver can be significantly reduced, extending the subject vehicle stopping distance. GM stated that the root cause of pump failures was due to foreign debris such as oil sludge in the engine oil. GM stated that this debris can become trapped by the oil inlet filter screen. Under normal operation, this screen allows a small amount of oil into the brake vacuum pump. The foreign debris can, over time, clog the pump which can cause a loss of lubrication and a reduction in the amount of vacuum produced leading to a hard pedal and extended stopping distance.On December 13, 2018, GM issued a Special Coverage (N182202780) for the brake vacuum pump issue in MY 2014-2017 trucks and 2015-2017 SUVs on the K2XX platform for 6 years or 72,000 miles. Special Coverage repair includes the replacement of the vacuum pump and vacuum pump belt. Consumers received notification of the coverage via mail. On September 6, 2019, GM notified NHTSA that it was conducting safety recall 19V-645 which reprograms the electronic brake control module (EBCM) and included approximately 3.5 million trucks and SUVs. In October 2019, GM extended the terms of special coverage N182202780 to 10 years or 150,000 miles as well as now including the entire scope of recall 19V-645. In October 2020, GM expanded the scope of coverage N182202780 to include the MY 2018 Escalade and 2019 Tahoe.The remedy implemented in GM recall 19V-645 appears to be sufficient in addressing the safety-related concerns of this issue. Loss of vacuum assist now occurs at a progressive rate as well as there being a more timely warning of a brake problem to the driver through the driver information center (DIC). In view of the recall action and revision to the special coverage, this Preliminary Evaluation is closed. The agency reserves the right to take additional action if warranted by new circumstances. The ODI reports cited above are available for review online at NHTSA.gov under the identification numbers in the attached document.
Service Brakes, Hydraulic:power Assist:vacuum
On November 20, 2018, the Office of Defects Investigations (ODI) opened PE18-012 to investigate instances of sudden onset of a hard brake pedal that could result in extended stopping distance due to an issue with the brake assist vacuum pump in model year (MY) 2014 through 2016 GMC Sierra 1500 and Chevrolet Silverado 1500 series pickup trucks and MY 2015 through 2016 Cadillac Escalade, Chevrolet Suburban, Chevrolet Tahoe, and GMC Yukon SUVs.If the brake assist vacuum pump fails to operate as intended, the amount of brake power assist supplied to the driver can be significantly reduced, extending the subject vehicle stopping distance. GM stated that the root cause of pump failures was due to foreign debris such as oil sludge in the engine oil. GM stated that this debris can become trapped by the oil inlet filter screen. Under normal operation, this screen allows a small amount of oil into the brake vacuum pump. The foreign debris can, over time, clog the pump which can cause a loss of lubrication and a reduction in the amount of vacuum produced leading to a hard pedal and extended stopping distance.On December 13, 2018, GM issued a Special Coverage (N182202780) for the brake vacuum pump issue in MY 2014-2017 trucks and 2015-2017 SUVs on the K2XX platform for 6 years or 72,000 miles. Special Coverage repair includes the replacement of the vacuum pump and vacuum pump belt. Consumers received notification of the coverage via mail. On September 6, 2019, GM notified NHTSA that it was conducting safety recall 19V-645 which reprograms the electronic brake control module (EBCM) and included approximately 3.5 million trucks and SUVs. In October 2019, GM extended the terms of special coverage N182202780 to 10 years or 150,000 miles as well as now including the entire scope of recall 19V-645. In October 2020, GM expanded the scope of coverage N182202780 to include the MY 2018 Escalade and 2019 Tahoe.The remedy implemented in GM recall 19V-645 appears to be sufficient in addressing the safety-related concerns of this issue. Loss of vacuum assist now occurs at a progressive rate as well as there being a more timely warning of a brake problem to the driver through the driver information center (DIC). In view of the recall action and revision to the special coverage, this Preliminary Evaluation is closed. The agency reserves the right to take additional action if warranted by new circumstances. The ODI reports cited above are available for review online at NHTSA.gov under the identification numbers in the attached document.