2018 Buick Enclave

I am the original owner of this Buick Enclave Avenir. I have had two near accident occurences when the car started foring the breaks while I was accellarating on the highway and was not behind another vehicle. The car behind me nearly rerended me. On 10/17/26, my purge valve was replaced for the third time, making this the fourth purge valve the car has had. After getting gas, the car will not start, which is an indicator the part has gone bad and needs to be replaced. In June of 2025 I took my car to Anderson Buick over concerns while accellerating. They confirmed my transmission needed to be replaced. Our family shop suggested waiting until the end of summer since I wouldnt be driving daily and the replacement would cost nearly 10k. It could only be ordered through GM, making the part substantially higher in cost. When summer break ended and I needed to use my car daily we could not take the car to the dealer or our family shop because the part was no longer available. We could not get a clear time frame of when the part would be in stock, if at all. We had the transmission rebuilt with 166k miles. Nearly 4 months later the trasmission started to shudder again. We took it back to the same shop for repairs becuase it was under warranty. Nearly four months later, the issue began again. The shop said there is nothing I can do to stop it from happening, that the part is deffective and GM knows. I have opened a claim with GM and expect nothing will happen, but it is apparent that the transmission issues are rampant with this vehicle, as evidenced by the complaints here and the droves of complaints on reddit forums.

NHTSA ID

11771938

Incident

Sep 9, 2026

The vehicle is experiencing an intermittent but severe safety defect involving the StabiliTrak and Electronic Parking Brake (EPB) systems. While driving at operational speeds, the "Service StabiliTrak" warning light illuminates, immediately followed by the uncommanded, autonomous engagement of the electronic parking brake. When the defect occurs, the vehicle forcibly brakes itself and suffers a complete loss of throttle response, preventing acceleration. This creates a severe, immediate crash hazard, as the vehicle decelerates abruptly without warning to surrounding traffic, leaving the driver unable to accelerate out of harm's way.The vehicle was brought to an authorized General Motors dealership multiple times during the active warranty period for recurring StabiliTrak system warnings. The manufacturer failed to permanently diagnose and resolve the root cause of the Electronic Brake Control Module (EBCM) failure. The vehicle remains highly dangerous to operate due to unpredictable, uncommanded braking.

NHTSA ID

11766879

Incident

Sep 24, 2026

2018 Enclave w/106k on the odometer and the catalytic convertor cracked. $2200 repair.

NHTSA ID

11744702

Incident

Jun 1, 2026

I am submitting this letter to formally report two ongoing issues with my 2018 Buick Enclave. First, I have experienced persistent problems with the emissions purge valve. My vehicle has repeatedly triggered diagnostic trouble code P0496, indicating a malfunction in the purge valve system. I am aware that this issue has been the subject of recall campaigns for other Buick Enclave models; however, my vehicle has not been included in any such recall, despite exhibiting the same symptoms. This malfunction has resulted in persistent check engine warnings and noticeable performance concerns, raising questions about emissions compliance and the overall reliability of my vehicle. Given that other vehicles of the same make and model year have been recalled for the same issue, I respectfully request that my vehicle be reviewed for inclusion in the recall. Second, I am formally reporting a malfunction involving the stabilizers. Recently, I have noticed unusual noises and instability when driving, particularly when turning or traveling over uneven surfaces, which indicates a potential stabilizer malfunction. These issues have persisted despite regular maintenance and inspections, affecting the handling and safety of the vehicle. I believe this may represent a manufacturing or design defect that could pose a risk to other owners of the same make and model. I respectfully request that the National Highway Traffic Safety Administration investigate this matter further. I kindly ask the National Highway Traffic Safety Administration to consider expanding the existing recall to encompass additional vehicles affected by this defect. Please advise if you require further information or documentation regarding my case. Sincerely, [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11742783

Incident

Jun 1, 2026

The contact owns a 2018 Buick Enclave. The contact stated that while driving at various speeds, the vehicle shut off and failed to restart. The vehicle was towed to the dealer, where the alternator was replaced 4 times before the dealer diagnosed that the failure was due to oil leaking onto the alternator and the battery. The contact stated that the alternator had been replaced 6 times in total. Additionally, the contact stated while pulling out of the parking lot and onto the road, the vehicle shut off. The messages "Electronic Control Module Failure", "Battery Saver Active", "Battery Charging System" and "Steering Assist Is Reduced- Drive with Care" were displayed. The vehicle failed to restart and was towed to the dealer, where it was diagnosed with the Electronic Control Module (ECM) and alternator failures. The vehicle was being repaired. The manufacturer was notified of the failure. The failure mileage was approximately 72,000.

NHTSA ID

11740184

Incident

May 26, 2022

Mileage

72,000 mi

After two transmission flushes and being told by a Buick dealership's service technicians that nothing is wrong with the vechile's transmission, it has now failed completely at ~90k miles.

NHTSA ID

11737422

Incident

May 12, 2026

Catalic converter weld broke both sides now

NHTSA ID

11737064

Incident

Feb 1, 2026

Exhaust leak from broken front exhaust pipe. This has been a known defect in this make/model however the year of my vehicle was not included in the extended repair window and should have been. The exhaust leak was identified by the dealership when the vehicle was taken in for other maintenance. I had to pay for the repair myself and would like to be reimbursed due to this being a manufacturer known defect with the exhaust pipe. The exhaust leak caused unusual noises, a loud roaring, and reduced gas mileage. This was also a danger for carbon monoxide exposure.

NHTSA ID

11735792

Incident

Oct 20, 2025

This Preliminary Information communication provides information to the technician about vehicles that have an intermittent no crank, no start, or start stall concern with the security light coming on. Technician may find Diagnostic Trouble Codes B3055, B3

This PI provides Diagnostics tips on how the LIN bus works and how to diagnosis it.

This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.

PI to help diagnose A/C concern

This preliminary information communicates information about how to determine if a wheel and tires size change is available.

This Preliminary information communicates the steps on how to save a GDS2 Session Log and upload to a Technical Assistance Case in CX Connect.