The 2019 Cadillac CT6 with the 4.2L Blackwing twin-turbo V8 and all-wheel drive gets 17 MPG combined. Clients who choose this CT6 variant aren’t surprised by its gas-guzzling status. They want effortless power, composed handling, and American luxury, and they’re willing to make concessions at the pump to get it. This isn’t a car purchased for hypermiling or minimizing running costs; it’s a statement.

City and highway performance

The EPA estimates the CT6 Blackwing’s fuel economy at 14 MPG in the city and 25 MPG on the highway. That city number reflects the reality of moving a substantial sedan with a powerful V8 in stop-and-go traffic. The highway figure is more respectable, suggesting that the 10-speed automatic transmission helps the car on longer cruises, keeping the engine efficient at higher speeds. However, aggressive acceleration or sustained high-speed runs diminish those highway gains quickly.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2019 Cadillac CT6 AWD 4.2L Blackwing at $3,400. This is based on driving 15,000 miles per year, with 55% of those miles driven in the city and 45% on the highway, using national average fuel prices. Buyers considering this car shouldn’t be shocked by this figure. The estimate is affected by individual driving habits. The V8 power comes at a cost.

Real-world expectations

EPA estimates provide a baseline, but real-world fuel economy varies depending on driving style, traffic, and fuel type. If your driving involves short trips, frequent stops, and a heavy foot, expect closer to the city figure than the combined number. Longer highway journeys with consistent speeds should yield results closer to, or slightly above, the 25 MPG highway estimate. Don’t be surprised to see averages dip below 15 MPG during enthusiastic driving or in congested urban areas. It can be easy to find yourself dipping into the boost more often than you intend because the Blackwing engine is responsive.

How it compares

The CT6 Blackwing’s fuel economy isn’t its strongest feature when compared to rivals. The BMW M5, for example, posts a combined 17 MPG, identical to the CT6, but offers superior performance. The Mercedes-AMG E63 S manages a combined 19 MPG despite similar horsepower. Even the less powerful Genesis G90 5.0L V8 achieves 19 MPG combined. Buyers often cross-shop between brands, weighing power, luxury, and efficiency. While the Cadillac might fall slightly behind in fuel economy, its American character and lower price point might still sway some buyers. Check CT6 MPG across all years to see if other trim levels are a better fit.

Tips to maximize efficiency

While the CT6 Blackwing isn’t designed for optimal fuel economy, you can take steps to minimize fuel consumption. Avoid aggressive acceleration and hard braking. The Blackwing V8 is responsive, but gentle throttle inputs will significantly reduce fuel usage, especially in city driving.

Ensure your tires are properly inflated. Underinflated tires increase rolling resistance, forcing the engine to work harder and consume more fuel. Check your tire pressure regularly and maintain the recommended levels found on the driver’s side doorjamb or in the owner’s manual.

Limit idling time. Idling consumes fuel without covering any distance. If you’re waiting for more than a minute or two, turn off the engine. The CT6’s start/stop system can assist with this in certain situations, but be mindful of its operation and potential impact on overall driving experience.

Consider using premium fuel. Premium fuel with a higher octane rating may slightly improve performance and fuel economy, particularly under demanding driving conditions. Consult the owner’s manual for recommendations on fuel type.

Keep up with scheduled maintenance. Regularly servicing your CT6, including oil changes, air filter replacements, and spark plug maintenance, will ensure the engine runs efficiently. Neglecting maintenance can lead to decreased performance and increased fuel consumption. For all Cadillac fuel economy data, see our other guides.