21 MPG combined is what you can expect from the 2021 Cadillac CT5 with all-wheel drive and the strong 3.0L twin-turbo V6. It won’t win any fuel economy contests, but that number is a compromise most CT5 AWD 3.0T buyers accept. This isn’t about hypermiling; it’s about enjoying a responsive, confident driving experience in a stylish and comfortable sedan. It’s a car for someone who values performance and all-weather traction over frugality at the pump, and for whom the Cadillac badge still appeals.

City and highway performance

The EPA estimates of 18 MPG in the city and 26 MPG on the highway realistically portray the CT5 AWD 3.0T’s appetite for fuel. The city figure reflects the demands placed on the engine during stop-and-go driving, where the turbochargers are constantly spooling and the engine is working harder. The highway number, while better, isn’t exceptional, likely due to the AWD system adding weight and parasitic loss. This setup prioritizes power delivery and predictable handling, especially in inclement weather, which impacts fuel efficiency. The ten-speed automatic transmission tries its best to keep the engine in its optimal range, but the engine’s inherent thirst is difficult to overcome completely.

Annual fuel cost

According to the EPA, the annual fuel cost for the 2021 Cadillac CT5 AWD 3.0L is $2,750. This figure is based on driving 15,000 miles per year and using the EPA’s combined MPG rating, and national average fuel prices for premium gasoline. The actual cost will vary based on individual driving habits, local fuel prices, and the percentage of city versus highway driving. However, $2,750 provides a useful benchmark for prospective buyers to factor into their budget when considering this car.

Real-world expectations

While the EPA estimates provide a baseline, real-world fuel economy often differs. Aggressive driving, frequent short trips, and even tire pressure can impact the numbers you see on the CT5’s trip computer. Owners primarily driving in urban areas will likely see figures closer to the 18 MPG city rating. Those who spend most of their time on the open road may achieve slightly better than 26 MPG. However, expecting significantly better fuel economy than the EPA estimates is unrealistic with this powertrain, especially if you frequently use the V6’s power.

How it compares

In the competitive compact luxury sedan segment, the CT5 AWD 3.0L generally falls toward the lower end of the fuel economy spectrum. For example, the BMW 330i xDrive, while also requiring premium fuel, achieves a combined EPA rating of 28 MPG, a significant advantage. Even the more powerful BMW M340i xDrive manages 25 MPG combined. The Audi A4 allroad, with its standard all-wheel drive, boasts 24 MPG combined. While these competitors may offer slightly less horsepower than the V6 CT5, their turbocharged four-cylinder engines are more fuel-efficient, and that’s a trade-off some buyers accept. For those prioritizing fuel economy within the Cadillac lineup, exploring models like the standard CT5 with the 2.0L turbo engine or viewing all Cadillac fuel economy data might be worth considering. You can also view CT5 MPG across all years to consider a different powertrain or model year.

Tips to maximize efficiency

Avoid aggressive acceleration and braking. The CT5’s turbochargers deliver a surge of power when you demand it, but that comes at a cost. Smooth and gradual acceleration will help keep the turbos from boosting unnecessarily, conserving fuel. Similarly, anticipate traffic and brake gently, allowing the engine to coast when possible.

Maintain proper tire inflation. Underinflated tires increase rolling resistance, forcing the engine to work harder and consuming more fuel. Check your tire pressures regularly, ideally every week, and inflate them to the recommended levels listed on the door jamb sticker. You can use a digital TPMS sensor to remind you when pressures are low.

Reduce unnecessary weight. Carrying extra weight in the trunk or backseat will negatively impact fuel economy. Remove any items you don’t need on a regular basis. Even small amounts of excess weight can add up over time and decrease your MPG, particularly in city driving.

Use cruise control on the highway. Cruise control helps maintain a consistent speed, minimizing unnecessary acceleration and deceleration. This can improve fuel economy on long highway drives, especially on relatively flat terrain. Just remember it is not suitable for stop-and-go traffic or challenging road conditions.