Photo: Wikimedia Commons (CC)
Power
0–62 mph (0–100 km/h)
Combined, EPA 2020
What owners say
Our take, from owner reports
Mixed sentiment with a clear divide between appreciation for the vehicle's core attributes and significant concerns over reliability and long-term viability.
6 problems reported (4 very frequent, 2 recurrent) · high confidence
Problems owners report
- Very frequentUnreliable electronics and poor build quality
Electronics stop working randomly all over the car.
- Very frequentProblematic 8-speed automatic transmission (8L45 and 8L90)
Harsh shifting, jerkiness, especially in 2nd gear, laggy response, subject to class action lawsuits.
- Very frequentSevere engine cooling issues (CT6-V 4.2L Twin-Turbo V8)
Engines can burst into flames after hard driving, leading to parking outside as a precaution; described as a fundamental design flaw.
+ 3 more issuesShow fewer
- Very frequentParts availability and cost
Many parts are exclusive to the CT6, making them hard to source and very expensive, a major concern for long-term ownership.
- RecurrentCUE infotainment system
Complicated menu layout, sluggish response, noticeable lag, screen freezes, requires costly replacements.
- RecurrentCamera/recording system failures
Particularly on 2019 models, fails to record drives and security events, can be triggered by specific phone connections, no fix available.
The version owners recommend
Insufficient owner data available to declare a consensus "best" trim. The high-performance CT6-V with the 4.2L Twin-Turbo V8 (Blackwing) is mentioned as a rare, fun halo car but is universally flagged for severe reliability concerns and future parts scarcity. The 3.0L Twin-Turbo V6 models are presented as a more sensible performance choice, offering over 400 horsepower. Plug-in Hybrid models are mentioned but not evaluated in depth.
Competitors to consider
Owners compare it most often with the Lexus LS, BMW 7-Series, Mercedes-Benz S-Class, Genesis G90 and Audi A8.
Is the CT6 right for you?
Get an answer for your year, mileage and budget.
Full owner reportHide full owner report
Overall sentiment
Mixed sentiment with a clear divide between appreciation for the vehicle's core attributes and significant concerns over reliability and long-term viability. The CT6 is widely praised for its driving dynamics, particularly on the advanced Omega platform, which is noted for excellent handling and weight transfer. It is considered a cutting-edge luxury machine offering strong value, especially when purchased used, with powerful engine options (notably the 3.0L Twin-Turbo V6 and the rare 4.2L Twin-Turbo "Blackwing" V8) providing substantial performance. The interior is described as luxurious, with specific praise for the available Panaray audio system and Super Cruise hands-free highway driving system. However, this is heavily counterbalanced by very frequent and severe criticisms of poor build quality, unreliable electronics, problematic transmissions, and major concerns about parts availability and catastrophic engine failures in high-performance variants. The consensus indicates it can be a compelling used luxury sedan for driving enthusiasts willing to accept significant reliability risks, but is not recommended for those seeking trouble-free ownership.
Positioning vs competitors
Positioned as a technologically advanced, driver-focused luxury flagship offering superior handling and a better value proposition than German rivals (BMW 7-Series, Mercedes S-Class, Audi A8) on the used market. It is frequently compared to the Lexus LS and Genesis G90, with owners acknowledging the Asian competitors offer superior reliability, lower running costs, and better durability, though potentially with less engaging dynamics. The CT6 is seen as undercutting competitors on price for similar power and feature content but is critically hampered by a reputation for poor reliability and expensive, hard-to-source repairs.
Recommended configurations
3.0L Twin-Turbo V6 engine is recommended over base four-cylinder for adequate power. Super Cruise hands-free highway system is noted as a valuable advanced feature. AWD is mentioned as an available option. Owners strongly recommend purchasing an extended warranty due to pervasive reliability concerns. For the CT6-V, an explicit recommendation *against* purchase is made due to engine fire risks and parts availability.
General recommendations
Suitable only for knowledgeable buyers comfortable with potential high repair costs and sourcing difficulties. Strongly recommended for driving enthusiasts who prioritize handling and performance over luxury refinement and reliability. A comprehensive pre-purchase inspection by a specialist is essential. An extended warranty is considered mandatory by many owners. Not recommended for buyers seeking a low-maintenance, dependable luxury sedan; Lexus LS or Genesis G90 are consistently suggested as more reliable alternatives. For those considering a CT6-V, owners and industry sources explicitly warn against purchase due to severe, unresolved engine cooling issues that can lead to fires, and the imminent impossibility of sourcing unique powertrain parts.
Remarks
The CT6's lifecycle was marked by its advanced Omega platform, which delivered exceptional driving dynamics for a large sedan, but was ultimately undermined by GM's poor execution of critical components and lack of market support. The unique 4.2L Blackwing V8, installed in fewer than 1,500 vehicles, is described as an engineering failure with dangerous, unresolved defects that led to the engine's cancellation and will render CT6-V models unserviceable in the future. The vehicle was discontinued in the North American market but remains in production for China, a point of frustration for some owners. High depreciation makes used examples appear as strong value propositions, but the total cost of ownership is likely elevated due to the frequency and expense of repairs. Analysis based on owner discussions spanning the 2016-2020 model years.
Generation by generation
Owner insights per generation and US complaint/recall records (NHTSA).
Complaints and recalls by model yearNo year grades F. Best year: 2016Source: NHTSA (US)Show table
Each year graded against the model's other years: Year Score.
| Year | Complaints | Recalls | Most-reported area |
|---|---|---|---|
| 2020 | 20 | 2 | power train |
| 2019 | 18 | 4 | power train |
| 2018 | 20 | 2 | engine |
| 2017 | 49 | 2 | power train |
| 2016 | 11 | 3 | power train |
Complaint counts come from owner reports filed with the US National Highway Traffic Safety Administration. Higher-selling years naturally accumulate more complaints.
Recall notices13 on record · Source: NHTSA (US)Show recalls
2020 · tires:pressure monitoring and regulating systemscampaign 19V731000
General Motors LLC (GM) is recalling certain 2020 Cadillac CT6 vehicles equipped with dealer-installed accessory 20" x 8.50" wheels (RPO 5JO or SHH). The tire pressure monitoring system (TPMS) sensors use the incorrect wireless radio frequency and cannot illuminate the low pressure warning light when the tire pressure drops below the recommended level. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 138, "Tire Pressure Monitoring Systems."
2020 · power train:automatic transmissioncampaign 25V148000
General Motors LLC (GM) is recalling certain 2019-2020 Cadillac CT6, 2020-2021 CT4, CT5, and 2020-2022 Chevrolet Camaro vehicles equipped with a 10-speed transmission. The transmission may become damaged internally and cause the wheels to lock-up.
2019 · service brakes, hydraulic:antilock/traction control/electronic limited slip:abs warning lightcampaign 19V889000
General Motors LLC (GM) is recalling certain 2019 Chevrolet Silverado 1500, Cadillac CT6, and GMC Sierra 1500 vehicles. Due to an Electronic Brake Control Module (EBCM) software error, the vehicle's Electronic Stability Control (ESC) and Antilock Brake System (ABS) may become disabled. Furthermore, if this specific error occurs, the vehicle's diagnostics will not illuminate the instrument cluster ESC and ABS malfunction warning lights. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 126, "Electronic Stability Control" and 135, "Light Vehicle Brake Systems."
2019 · exterior lighting:turn signal:switchcampaign 19V117000
General Motors LLC (GM) is recalling certain 2019 Cadillac CT6 vehicles. Rotation of the steering wheel will not automatically cancel the turn-signals from flashing. As such, these vehicles fail to comply with Federal Motor Vehicle Safety Standard (FMVSS) number 108, "Lamps, Reflective Devices and Associated Equipment."
2019 · seat belts:rear/othercampaign 18V673000
General Motors LLC (GM) is recalling certain 2018-2019 Cadillac CT6, Escalade ESV, Chevrolet Suburban, Volt, and GMC Yukon XL vehicles. Certain second-row or third-row rear seatbelts retractor assemblies may not automatically lock when the seatbelt is fully pulled out of the retractor, possibly preventing a child seat from being properly secured. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 208, "Occupant Crash Protection."
2019 · power train:automatic transmissioncampaign 25V148000
General Motors LLC (GM) is recalling certain 2019-2020 Cadillac CT6, 2020-2021 CT4, CT5, and 2020-2022 Chevrolet Camaro vehicles equipped with a 10-speed transmission. The transmission may become damaged internally and cause the wheels to lock-up.
2018 · seat belts:rear/othercampaign 18V673000
General Motors LLC (GM) is recalling certain 2018-2019 Cadillac CT6, Escalade ESV, Chevrolet Suburban, Volt, and GMC Yukon XL vehicles. Certain second-row or third-row rear seatbelts retractor assemblies may not automatically lock when the seatbelt is fully pulled out of the retractor, possibly preventing a child seat from being properly secured. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 208, "Occupant Crash Protection."
2018 · seats:mid/rear assemblycampaign 18V437000
General Motors LLC (GM) is recalling certain 2016-2018 Cadillac CT6 vehicles. The inboard child seat anchorage bars may have had excess structural adhesive applied during assembly, which can interfere with the installation of a child seat. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 225, "Child Restraint Anchorage Systems."
2017 · seats:mid/rear assemblycampaign 18V437000
General Motors LLC (GM) is recalling certain 2016-2018 Cadillac CT6 vehicles. The inboard child seat anchorage bars may have had excess structural adhesive applied during assembly, which can interfere with the installation of a child seat. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 225, "Child Restraint Anchorage Systems."
2017 · exterior lightingcampaign 21V759000
General Motors, LLC (GM) is recalling certain 2016-2017 Cadillac CT6 vehicles. The Park/Position lights may be excessively bright. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 108, "Lamps, Reflective Devices, and Associated Equipment."
2016 · seats:mid/rear assemblycampaign 18V437000
General Motors LLC (GM) is recalling certain 2016-2018 Cadillac CT6 vehicles. The inboard child seat anchorage bars may have had excess structural adhesive applied during assembly, which can interfere with the installation of a child seat. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 225, "Child Restraint Anchorage Systems."
2016 · seat belts:front:webbingcampaign 16V687000
General Motors LLC (GM) is recalling certain model year 2016 Cadillac CT6 vehicles manufactured July 21, 2016, to July 22, 2016. The bolt that connects the front passenger seat belt webbing to the seat's anchor plate may be missing. Without the bolt, the seat belt webbing may detach from the seat anchor.
2016 · exterior lightingcampaign 21V759000
General Motors, LLC (GM) is recalling certain 2016-2017 Cadillac CT6 vehicles. The Park/Position lights may be excessively bright. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 108, "Lamps, Reflective Devices, and Associated Equipment."
Specifications
V Blackwing 4.2 V8 Hydra-Matic
4.2L 8-cylinder · 550 hp · AWD · automatic
Built 2019–2020