2015 GMC Yukon XL Problems

What owners report

Owners of this model year most often report rear tail and brake light assemblies that stop illuminating, usually without any dashboard warning. Transmission shudder and harsh shifts, a stiff brake pedal when vacuum assist is lost, and engine valvetrain noise or internal damage also recur in the sample. Reports cluster broadly between roughly 30,000 and 145,000 miles, with lighting and brake complaints appearing at low speed or while parked and engine complaints mostly above 100,000 miles.

1. 1
   Exterior lighting

   Rear LED tail and brake lights stop working

   • 160 complaints (52%)
   • median 69,000 mi at 4.6 yrs old (117 state mileage)
   • 2 mention a crash, fire or injury
   • owner-quoted repair $800 (median of 52 quotes)
   • filed 2018–2026

   Owners describe one or both rear lamp assemblies going dark, often intermittently at first and then permanently, while the turn signal and reverse light keep working. Many only learn of it when another driver points it out, and dealers replace the whole sealed assembly rather than a bulb, which owners describe as costing several hundred dollars per side. Several complaints note the replacement unit stopped working again within months, and that a warranty extension was declined once the vehicle passed its mileage limit. Reported from roughly 30,000 to 115,000 miles, most often between 50,000 and 100,000 miles, with no clear weather pattern.

   1 related service bulletin

   What to check: With the engine running, have someone watch each rear lamp while you press the brake pedal and switch the lights on, and check whether either assembly has already been replaced.

   2 excerpts from owner complaints in NHTSA records

   “No brake light in both rear lighting assemblies. Started with the passenger side and now the drivers side. Gmc issued a letter in december 2019 stating they'd pay for repairs if vehicle is less than 6 years or 75,000 miles which ever comes first. We'll I'm over on both. Gmpp extended warranty doesn't cover this repair. Spend $75k for this truck and now this.”

   NHTSA complaint #11317228, filed 2020-03, 85,000 miles

   “Both tail lights (brake lights and running lights in red) stop working with no warning to the driver. Third brake light does continue to work. This is noticed when parked and when in motion. This is a safety issue for other drivers crashing into our vehicle because they do not know that we are braking. A friend had to point this out to us in the school pickup line. First noticed on 2/13/20. Had to buy two new taillight assemblies and install.”

   NHTSA complaint #11321286, filed 2020-04, 96,500 miles
2. 2
   Transmission and drivetrain

   Transmission shudder, hard shifts and slipping

   • 25 complaints (8%)
   • median 75,000 mi at 4.9 yrs old (15 state mileage)
   • 3 mention a crash, fire or injury
   • filed 2015–2026

   Owners describe a shudder or shake while accelerating or holding highway speed, hard or delayed engagement when the transmission is cold, and jerky low-speed shifts. Dealers have flushed the transmission fluid or replaced the torque converter, and in some cases owners were told the behavior was normal until slipping or a loss of drive developed. A few complaints describe the transmission locking up or dropping into neutral so the vehicle would not move. Usually reported between 70,000 and 180,000 miles, though some owners noticed harsh shifts much earlier.

   2 related service bulletins

   What to check: On the test drive, pull away gently from a stop and hold a steady 45-55 mph on a smooth road to feel for shudder; ask whether the fluid has been serviced or the torque converter replaced.

   2 excerpts from owner complaints in NHTSA records

   “My 2015 Yukon Xl slt transmission developed a stutter while going along accelerating but would go away as you drive. Unfortunately this came to an abrupt end this past january when I jumped in it and went about 50 feet and the vehicle sounded like it was in neutral and I couldn't go anywhere without cutting it off and starting over which only caused the process to repeat.. I had my mechanic tow it to their shop and diagnose the problem. The told me the transmission was malfunctioning. …”

   NHTSA complaint #11394399, filed 2021-02, 162,000 miles

   “The yukon's automatic transmission can get very jerky when accelerating from a stop, especially when the engine is cold (first 10-15 mins of driving). City driving seems to be the main environment when the transmission jerkiness occurs. The jerkiness started subtly around 75,000 miles, and now at almost 100k miles, the issue has only gotten more severe. Accelerating from a stop uphill and around turns are times when it's more prone to jerk. …”

   NHTSA complaint #11309043, filed 2020-02, 75,000 miles
3. 3
   Brakes

   Stiff brake pedal, loss of power assist

   • 44 complaints (14%)
   • median 82,800 mi at 4.5 yrs old (30 state mileage)
   • 3 mention a crash, fire or injury
   • owner-quoted repair $800 (median of 5 quotes)
   • filed 2017–2026

   Owners describe a brake pedal that becomes hard and stiff, so the vehicle keeps rolling at low speed unless they press with both feet. Dealers traced the problem to little or no vacuum reaching the brake booster and replaced the vacuum pump, and in some cases the booster as well. A smaller number of complaints mention a pedal that went to the floor or a brake that pulled to one side. Reported from about 45,000 to 145,000 miles, most often while braking at low speed, at a stop light or in a parking lot.

   What to check: Test the brakes at walking pace in an empty lot and feel for a pedal that firms up or a longer-than-expected stop, and ask for service records on the vacuum pump and brake booster.

   2 excerpts from owner complaints in NHTSA records

   “The brakes on my 2015 Gmc yukon suddenly became extremely difficult to operate with very hard brake pedal and increased stopping distance. I was able to bring the vehicle to the dealer for service. They informed me that there was no output from the engine vacuum pump to the brake booster and it would be addressed under a special coverage warranty from GM repaired. …”

   NHTSA complaint #11373489, filed 2020-11, 107,000 miles

   “The brakes failed in my car causing a rear collision with an object in my driveway. After inspection from a certified Gmc dealership, the brake failure was not caused by service neglect or age of brakes, it was due to the vaccum pump failure to provide pressure. This is the second time in two years this part has caused my brakes to fail. The dealership replaced the part at no cost though there is not formal recall on this part. Both times this part failed the car was in motion. …”

   NHTSA complaint #11378243, filed 2020-12, 136,000 miles
4. 4
   Engine

   Engine lifter, camshaft and internal damage

   • 20 complaints (6%)
   • median 112,000 mi at 10.2 yrs old (9 state mileage, few)
   • 1 mention a crash, fire or injury
   • filed 2019–2026

   Owners describe a ticking or tapping from the engine bay, rough running, and in some cases the engine seizing or refusing to restart after a stall. Dealers diagnosed loose or damaged lifters, cylinder and camshaft damage, or a failed crankshaft, and recommended engine replacement. Complaints frequently note the repair was quoted at high cost and that mileage-based assistance was declined. Mostly reported between 100,000 and 130,000 miles.

   2 related service bulletins

   What to check: Listen for a tick or tap at a cold start, ask for oil change records, and have a scan tool check for stored misfire or valvetrain codes before buying.

   2 excerpts from owner complaints in NHTSA records

   “The contact owns a 2015 GMC Yukon XL. The contact stated that when the vehicle was started, the vehicle started shaking with a tapping sound coming from the engine compartment. The contact stated that there were no warning lights illuminated. The contact stated that while driving at an undisclosed speed around the block, the failure persisted. The vehicle was parked at the residence. …”

   NHTSA complaint #11703969, filed 2025-12, 100,000 miles

   “The contact owns a 2015 GMC Yukon. The contact stated that while attempting to accelerate from a stop, the vehicle experienced a loss of automotive power. and no warning lights were illuminated. The contact immediately pulled over, and the vehicle was towed to an independent mechanic to be diagnosed. The contact was informed that the crankshaft was faulty, and that the engine needed to be replaced. The vehicle was not repaired. …”

   NHTSA complaint #11659107, filed 2025-05, 112,000 miles
5. 5
   Steering

   Power steering assist loss and stalling

   • 17 complaints (6%)
   • median 72,000 mi at 5.1 yrs old (11 state mileage)
   • filed 2016–2025

   Owners describe the steering wheel suddenly becoming very hard to turn, sometimes with a service power steering message, and in other cases the engine shutting off at the same moment. Dealers have replaced the steering gear and battery cables, and some owners report the problem returned afterward. Several complaints note that dealers declined assistance under a recall once the vehicle was past a mileage limit. Reported between roughly 70,000 and 125,000 miles, often at highway or moderate speed.

   What to check: Ask whether the steering gear or battery cables have been replaced, and during the test drive note any stiffness, warning chime or brief loss of steering assist.

   2 excerpts from owner complaints in NHTSA records

   “I purchased my vehicle october 31'st 2019 from a local dealership. The milage was about 74k miles. I have only had this vehicle for a few months. My concern is the following. While driving, at least 7 to ten times the vehicle completely stalls. In other words it completely stops. The steering wheel locks. All power is lost. No lights no nothing. This has happened at intersections, it has happened when turning left, it has happened when turning right. It happens when we are yielding. Sometimes the dash starts to flicker and also the console. …”

   NHTSA complaint #11309700, filed 2020-02, 86 miles

   “The contact owns a 2015 GMC Yukon Denali XL. The contact stated that while driving at 75 MPH, the steering wheel hardened as both a warning chime and a service power steering warning message appeared on the instrument panel. The contact stated that he crossed two lanes of traffic before gaining control of the vehicle's power steering. Excessive force was used to steer the vehicle to his place of work. …”

   NHTSA complaint #11478575, filed 2022-08, 125,000 miles

Buying note. Check the rear lamp assemblies and the brake pedal feel before buying, since both are frequent and costly-to-repair complaints on this model year. Ask for transmission service records and listen for engine ticks at a cold start, as drivetrain complaints in the sample tend to appear past 70,000 miles.

Summary written with AI from a sample of 60 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.