2021 GMC Yukon driver assistance problems

Filed Sep 11, 2026 · Driver assistance, Engine · TX

Crankshaft / Camshaft caused catastrophic engine failure while on a family road trip leaving family and kids stranded on the side of the highway for hours. 2021 GMCs are notoriously having this issue but they refused to include our VIN in the recall. It cost us almost $13,000 to replace with a brand new engine and only 4 days after picking up from dealership the vehicle stopped working and shut off at a light in the middle of the road. GMC has been no help and won’t cover anything.

Filed Jul 27, 2026 · Driver assistance, Engine · 86,000 miles · MA

The contact owns a 2021 GMC Yukon. The contact stated that while driving at an undisclosed speed, there was a misfire coming from the vehicle, the vehicle was shaking and vibrating abnormally before the vehicle went into LIMP Mode. The traction control light and other unknown warning lights were illuminated on the instrument panel. The vehicle was taken to a dealer to be diagnosed. The vehicle was diagnosed with a lifter failure inside the engine. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was 86,000.

Filed Jun 30, 2026 · Driver assistance, Engine · FL

I bought the vehicle used with 40,000 miles it’s has 100,856 now the engine shot off while I was driving and brought it to the GMC dealer that GM instructed me to the dealer had me pay 284.95 for inspection and then try to charge me 1284.95 for a complete tar down of the engine because of misfiring and ESC error codes.

Filed Mar 20, 2026 · Driver assistance, Engine · 110,000 miles · NC

The contact owns a 2021 GMC Yukon. The contact stated that while driving at various speeds, the vehicle shuddered abnormally with blue smoke coming from the exhaust, with the message "Lane Departure Assist" displayed. The check engine and stabili-trak warning lights were illuminated. The vehicle was taken to a local service center, where it was diagnosed with cylinder #1 misfire. The local dealer was contacted. The vehicle was not diagnosed or repaired. Upon further investigation, the contact related the failure to the GMC Service Bulletin:15-06-01-002L. The manufacturer was made aware of the failure. The failure mileage was approximately 110,000.

Filed Jan 6, 2026 · Driver assistance, Engine · MD

I was driving and a message popped up "Service Traction Control", then another message popped up "Forward Collision System Unavailable". Then the car started making this knocking sound and every time I would try and accelerate there would be a loud sound and almost a pulling stopping it from picking up much speed. I took the car into the dealer/repair shop and they said it was an issue with the lifters that had to be replaced and potentially an issue with the cam. They said this repair would cost upwards of $6,000 and I have never had this issue with the car before. This came out of nowhere and the car had not been showing any signs of this occurring before. This is a 2021 GMC Yukon and I drive my Wife and three sons in that car daily.

Filed Dec 25, 2025 · Driver assistance, Engine · TX

traction control system ESC system Suddenly and without warning, multiple warning lights started flashing including check engine. The vehicle lost power and traction. There was a loud knocking and metallic whining sound. The vehicle began to vibrate and struggled to move forward and felt like the wheels were slipping. The loss of these functions was alarming because it was dark, we were in a construction zone, and my 15-year old daughter was driving having recently earned her driver's permit. The car following us almost rear ended us. It was such an abrupt engine failure it scared me and my daughter.

Filed Dec 22, 2025 · Airbags, Driver assistance · NC · crash · 1 injury

Vehicle: 2021 GMC Denali Mileage: ~48,000 miles Purchase Price: $62,000 Issue: Airbags & crash sensors failed to deploy Complaint Text: I am filing a safety complaint regarding my 2021 GMC Denali. I was involved in a rear-end collision at approximately 45 mph, where I struck another vehicle straight on from behind. The impact was severe enough to total my vehicle, yet no airbags deployed, and no forward collision warning or crash sensor systems activated. This is especially concerning because this vehicle was previously involved in a front-end collision (not my fault) and underwent extensive repairs. I was assured all systems were repaired and functioning properly. Additionally, my vehicle had completed recall work related to safety systems prior to this crash. This is the second front-end crash involving this vehicle where airbags failed to deploy. Given the speed and severity of the impact, airbags should have deployed. The failure of these systems placed my life at serious risk. The vehicle has since been totaled and taken by insurance, but I am requesting that this failure be formally investigated as a potential safety defect in the airbag and sensor systems. I am extremely concerned that the vehicle’s safety systems were either defective or not properly restored following repairs and recalls.

Filed Nov 13, 2025 · Driver assistance, Engine · AL

While driving vehicle on 11/08/2025, vehicle made a popping noise and loss power. We were out of town and had to pay out of pocket to have vehicle towed to a dealership and hour away from our home. Dealership diagnosed issue with engine failure due to lifter fell and caused damage to cam shaft and bore. I will be without a vehicle for an additional 2 to 4 weeks waiting on a back ordered engine from GM, and continue making payments on vehicle as well. This issue seems to be an ongoing problem that GM is ignoring…….GM should compensate towing, car rental, and repair/ replacement charges due to failure.

Filed May 5, 2025 · Driver assistance, Engine · 20,000 miles · CA

The contact owns a 2021 GMC Yukon. The contact stated that while driving at various speeds, the Forward Collision Avoidance system erroneously activated, causing the vehicle to suddenly slow down. The vehicle was taken to the local dealer who serviced the Forward Collision Avoidance system camera and sensors. No further information was available. Additionally, while driving at highway speeds, there was a knocking sound coming from the engine compartment, and the seat restraint failure message was displayed. The cause of the failure was not yet determined. The manufacturer was notified of the failure. The failure mileage was 20,000.

Filed Mar 11, 2025 · Driver assistance, Engine · 102,000 miles · FL

The contact owns a 2021 GMC Yukon. The contact stated that while his wife was driving at an undisclosed speed, the vehicle lost automotive power. The Electronic Stability Control warning light was intermittently illuminated. The vehicle was towed to a local independent mechanic where it was diagnosed with a spun rod bearing failure; however, further investigation was needed. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 102,000.