BMW · 2018
M6 Convertible 4.4L 8-cyl
✓ EPA Verified
Premium Gasoline
Subcompact Cars
Rear-Wheel Drive
City
14
MPG
Combined
16
MPG
Highway
20
MPG
Annual Fuel Cost
$3,600
Based on 15,000 miles/year · EPA estimates
vs avg gas vehicle
$1,450
more per year
Class Comparison — Subcompact Cars
Bottom 1%
Better than 1 out of 100 vehicles in its class for fuel efficiency.
This vehicle: 16 MPG
This vehicle
16 MPG
Class average
27 MPG
Class lowest
12 MPG
EPA Energy & Environment Scores
2
Energy Score
Out of 10
2
GHG Score
Out of 10
553 lbs
Annual CO₂
g/mile tailpipe CO₂
Yes
Start-Stop
Auto stop-start
Vehicle Specifications
Engine4.4L 8-cyl
TransmissionAutomatic (AM-S7)
DriveRear-Wheel Drive
Fuel TypePremium Gasoline
Vehicle ClassSubcompact Cars
Engine DescSIDI
Start-StopYes
EPA Vehicle ID38611

The 2018 BMW M6 Convertible gets 16 MPG combined. This isn’t a number that will surprise, or frankly even bother, the typical M6 buyer. They’re purchasing a visceral experience, a convertible grand tourer with a snarling twin-turbo V8 and a badge that speaks volumes. Fuel economy is a distant, almost irrelevant consideration when compared to 560 horsepower and the ability to dominate a winding road in a symphony of exhaust noise.

City and highway performance

The EPA estimates 14 MPG in the city and 20 MPG on the highway for the M6 Convertible. The city figure reflects the reality of stop-and-go traffic, where the hefty M6 and its potent V8 are least efficient. The highway figure is more attainable, especially on long cruises where the engine can settle into a more relaxed rhythm. However, even on the open road, the temptation to exploit the M6’s prodigious power will inevitably impact fuel consumption. The seven-speed M Double Clutch Transmission (AM-S7) is partly responsible; it doesn’t offer the same fuel-sipping potential as some of the more modern eight and nine-speed automatics found in competitors.

Annual fuel cost

The EPA estimates an annual fuel cost of $3,600 for the 2018 BMW M6 Convertible. This figure is based on driving 15,000 miles per year, with a mix of city and highway driving, and using the national average fuel price for premium gasoline. Of course, your actual costs will vary depending on your driving habits and local fuel prices. Drivers who accelerate hard and those stuck in congested urban environments can expect to exceed this estimate, while those who primarily use the M6 for long highway trips and adopt a more conservative driving style may see slightly lower costs.

Real-world expectations

Real-world fuel economy for the M6 Convertible often lags behind the EPA estimates. Aggressive acceleration, frequent use of the sport driving modes, and simply enjoying the car’s performance can easily drop the combined MPG into the low teens. Owners who prioritize fuel efficiency above all else are unlikely to be drawn to the M6 in the first place. This is a car bought with the heart, not strictly the head, and the compromises in fuel economy are simply part of the ownership experience. For a more diverse set of statistics, you might review M6 MPG across all years.

How it compares

Compared to its rivals, the M6 Convertible isn’t winning any fuel economy contests. The Mercedes-AMG SL63, with its similarly potent V8 engine, achieves a comparable 16 MPG combined. An Audi R8 Spyder, while boasting near-identical performance capabilities, gets around 17 MPG combined due to its V10 engine, however, its power output is close enough that potential buyers tend to weigh the two models against each other. Potential buyers could also be looking at the Porsche 911 Turbo Cabriolet, which achieves a slightly better 18 MPG combined, delivering similar performance with a more refined overall experience. These differences might seem marginal, but they are significant for the performance sector. Comparing it to the all Bmw fuel economy data might give you different points of reference.

Tips to maximize efficiency

Resist the urge to constantly exploit the engine’s power. The M6 is intoxicating, but mindful acceleration and smooth throttle inputs can significantly reduce fuel consumption.

Use the car’s driving modes. The “Efficient” mode (if equipped) will remap the throttle response and shift points to prioritize fuel economy. While it might diminish the M6’s sporting character, it’s a viable option for highway cruising or mundane commutes.

Maintain proper tire inflation. Underinflated tires increase rolling resistance, which forces the engine to work harder and consume more fuel. Check your tire pressures regularly and inflate them to the recommended levels.

Minimize idling. Idling the engine wastes fuel unnecessarily. If you’re stopped for more than a minute, turn off the engine. Modern engines are designed to restart quickly and efficiently, so there’s no need to let them idle.

Consider your routes. Avoiding congested areas and opting for routes with fewer stop-and-go situations can improve fuel economy in the city. Plan your trips to avoid peak traffic times, if possible.