What are the most common Cadillac CT6 problems?
According to Au7o's research across NHTSA recalls, manufacturer TSBs, and owner forum reports, the 2018 Cadillac CT6 has 10 documented issues. The most frequently reported are: Excess Adhesive Can Obstruct Child-Seat Anchorages (Recall 18V437), Harsh 1-2 Shifting and Delayed Reverse Engagement on the Eight-Speed Automatic, Rear Seat Belt Automatic Locking Retractor Fails to Lock for Child Seats (Recall 18V673). Of these, 4 are rated critical and should be addressed promptly.
Is the Cadillac CT6 reliable?
The 2018 Cadillac CT6 has 10 known issues compiled from NHTSA recalls, manufacturer TSBs, and owner forum reports. 4 issues are rated critical: Excess Adhesive Can Obstruct Child-Seat Anchorages (Recall 18V437) and Harsh 1-2 Shifting and Delayed Reverse Engagement on the Eight-Speed Automatic and Rear Seat Belt Automatic Locking Retractor Fails to Lock for Child Seats (Recall 18V673) and 3.0L Twin-Turbo (LGW) Turbocharger Turbine Wheel Failure — GM Service Update 17408. Prospective buyers should inspect for these issues and factor potential repair costs into their purchase decision. Regular maintenance following the manufacturer's schedule helps prevent many common problems.
How much does it cost to fix common Cadillac CT6 problems?
Repair costs for known Cadillac CT6 issues range from $0 to $6,500, depending on the specific problem and whether you choose DIY or professional repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.
What is the 2016-2018 Cadillac CT6 Excess Adhesive Can Obstruct Child-Seat Anchorages (Recall 18V437)?
On certain 2016-2018 Cadillac CT6 vehicles, excess structural adhesive on the inboard child-seat anchorage bars can interfere with correct child-seat installation. Severity: high.
What is the 2016-2018 Cadillac CT6 Harsh 1-2 Shifting and Delayed Reverse Engagement on the Eight-Speed Automatic?
Powertrain complaints are the single largest NHTSA complaint category for the 2017 CT6. Owners of 2016-2018 cars report harsh or banging engagement between first and second gear, unpredictable shift quality, a long delay when moving from neutral or park into reverse, and occasion… Repairs typically run $300-$5,500. Severity: high.
What is the 2018-2019 Cadillac CT6 Rear Seat Belt Automatic Locking Retractor Fails to Lock for Child Seats (Recall 18V673)?
GM recalled certain 2018-2019 Cadillac CT6 vehicles under NHTSA campaign 18V673 because second-row or third-row seat belt retractor assemblies may not switch into automatic locking mode when the belt is pulled fully out of the retractor. Automatic locking retraction is the mechan… Repairs typically run $0-$0. Severity: high.
What is the 2016-2018 Cadillac CT6 3.0L Twin-Turbo (LGW) Turbocharger Turbine Wheel Failure — GM Service Update 17408?
GM issued Service Update 17408 covering 2016-2018 Cadillac CT6 sedans built with the 3.0L V6 twin-turbo (RPO LGW) after turbochargers were found capable of shedding turbine-wheel material. Owners report a whistle, siren or grinding noise from the turbo area followed by a hard los… Repairs typically run $2,500-$6,500. Severity: high.
What is the 2016-2020 Cadillac CT6 Parasitic Battery Drain From Keyless Entry Module Polling for Approach Lighting?
CT6 owners report the 12-volt battery going flat after the car sits for a few days, sometimes flat enough that the electronic shifter and door handles will not respond and the car needs a jump. GM documents a cycling battery draw on 2016-2020 CT6 vehicles in preliminary informati… Repairs typically run $150-$900. Severity: medium.
What is the 2016-2020 Cadillac CT6 Failed Thermostat Sets P0128, Forces Cooling Fans to Run Constantly and Disables the A/C?
CT6 owners report the radiator cooling fans running at high speed all the time — including after shutdown — with the coolant temperature gauge reading cold, and in many cases weak heater output and the A/C refusing to engage. The root cause is a thermostat that fails stuck open. Repairs typically run $350-$800. Severity: medium.
What is the 2017-2018 Cadillac CT6 CT6 Plug-In Hybrid: Faulty Transmission Wire Harness Thermistor Crimp — Service Update N202318000?
GM issued Service Update N202318000 in July 2021 for 2017-2018 Cadillac CT6 Plug-In Hybrid sedans, covering about 551 vehicles. The transmission wiring harness in these cars can have a defective crimp at the thermistor — the temperature-sensitive resistor that reports transmissio… Repairs typically run $0-$0. Severity: medium.
What is the 2016-2018 Cadillac CT6 8L45/8L90 Eight-Speed Torque Converter Clutch Shudder — TSB 18-NA-355 Fluid Exchange?
CT6 sedans with the 8L45 and 8L90 eight-speed automatic (2016-2018 model years) develop a torque converter clutch shudder that owners describe as driving over rumble strips — a vibration or shake at light throttle around 25-50 mph as the converter locks. GM traced it to the origi… Repairs typically run $400-$1,100. Severity: medium.
What is the 2016-2018 Cadillac CT6 Panoramic Sunroof Guide Rail Contact Causes Roof Creak, Tick and Rattle — TSB 16-NA-370?
A widely reported CT6 complaint is a creaking, ticking, popping or double-click noise from the roof and headliner area, heard during turns, over uneven pavement, and when the sunroof operates. GM documented it in TSB 16-NA-370 for 2016-2017 CT6 sedans equipped with the sunroof, a… Repairs typically run $200-$3,000. Severity: low.
What is the 2016-2020 Cadillac CT6 Rear Camera Mirror Module Failure — Blank, Blurry or Distorted Streaming Mirror Image?
The CT6's rear camera mirror streams a live video feed from a roof-mounted rear camera onto the mirror glass. Owners report the feed going blank, showing a grainy, pixelated or heavily distorted picture, or losing focus so badly at night and in rain that the mirror is unusable. G… Repairs typically run $400-$1,500. Severity: low.
