Mercedes-Benz · 2021
AMG GT Roadster 4.0L 8-cyl
✓ EPA Verified
Premium Gasoline
Two Seaters
Rear-Wheel Drive
City
15
MPG
Combined
17
MPG
Highway
20
MPG
Annual Fuel Cost
$3,400
Based on 15,000 miles/year · EPA estimates
vs avg gas vehicle
$1,250
more per year
Class Comparison — Two Seaters
Bottom 14%
Better than 14 out of 100 vehicles in its class for fuel efficiency.
This vehicle: 17 MPG
This vehicle
17 MPG
Class average
21 MPG
Class lowest
14 MPG
EPA Energy & Environment Scores
3
Energy Score
Out of 10
3
GHG Score
Out of 10
533 lbs
Annual CO₂
g/mile tailpipe CO₂
Yes
Start-Stop
Auto stop-start
Vehicle Specifications
Engine4.0L 8-cyl
TransmissionAutomatic (AM7)
DriveRear-Wheel Drive
Fuel TypePremium Gasoline
Vehicle ClassTwo Seaters
Engine DescSIDI
Start-StopYes
EPA Vehicle ID43521

17 MPG combined isn’t a number any 2021 Mercedes-Benz AMG GT Roadster buyer will brag about, nor will it deter a single potential customer from experiencing the thrill this performance machine delivers. This hand-built, twin-turbo V8 roadster exists to stimulate the senses and deliver explosive acceleration, and while fuel efficiency is quantifiable, it plays a small role in the ownership experience of such a specialized vehicle.

City and highway performance

The EPA estimates for the 2021 AMG GT Roadster are 15 MPG in the city and 20 MPG on the highway. These figures reflect the inherent trade-off between raw power and fuel conservation. The AMG GT’s strong 4.0L 8-cylinder engine, capable of substantial performance, isn’t optimized for saving gas in stop-and-go traffic. The automatic (AM7) transmission does its best to manage the engine’s output, but bursts of acceleration and frequent braking in urban environments take their toll.

On the open road, with consistent speeds, the AMG GT Roadster fares slightly better, but its aerodynamic profile and relentless power still require a significant amount of fuel to maintain cruising speed.

Annual fuel cost

Owning an AMG GT Roadster comes with a price that extends beyond the initial purchase. The EPA estimates an annual fuel cost of $3,400 based on driving 15,000 miles per year and national average fuel prices. This calculation assumes a roughly even split between city and highway driving. Premium fuel is required for optimal performance, which can increase the actual cost if regional fuel prices are higher than the national average.

While this number seems substantial, it is unlikely to deter the typical AMG GT owner, who prioritizes performance and exclusivity over frugality.

Real-world expectations

While the EPA provides a standardized estimate, real-world MPG may vary depending on driving style and conditions. Drivers who frequently exploit the AMG GT Roadster’s performance potential will likely see numbers below the EPA estimates. Conversely, drivers who adopt a more relaxed approach on longer highway journeys might achieve slightly better fuel economy. Factors such as ambient temperature, tire pressure, and the use of accessories like air conditioning can also influence fuel consumption. Most owners are unlikely to prioritize fuel conservation over enjoying the car’s capabilities.

How it compares

In the realm of high-performance roadsters, the AMG GT Roadster’s fuel economy is similar to its competitors. The Porsche 911 Carrera S Cabriolet, for example, achieves a combined MPG of 20 with its 3.0L engine, slightly better than the AMG GT. The BMW Z4 M40i, with its smaller 3.0L inline-6, manages a respectable 25 MPG combined. However, potential AMG GT Roadster buyers often consider factors beyond fuel economy; they choose the AMG GT for its distinct styling, handcrafted engine, and the aggressive character that sets it apart from its rivals.

Buyers looking for improved fuel economy might cross-shop those other models, but for many, all Mercedes Benz fuel economy data will be secondary to the visceral experience only the GT Roadster can provide. To get a broader perspective, research AMG MPG across all years to see trends in fuel efficiency within the brand.

Tips to maximize efficiency

While fuel economy may not be a primary concern for AMG GT Roadster owners, there are steps they can take to minimize fuel consumption. Avoid aggressive acceleration and hard braking whenever possible. Smooth and gradual changes in speed can significantly improve fuel efficiency, especially in city driving.

Regular maintenance is critical for optimal performance and fuel economy. Make sure that the engine is properly tuned, the tires are inflated to the correct pressure, and the air filter is clean. A well-maintained engine will run more efficiently, reducing fuel consumption and emissions.

Minimize idling; modern engines consume fuel when idling, especially in stop-and-go traffic. If you anticipate a prolonged stop, consider turning off the engine to conserve fuel.

Plan routes to avoid congested areas and traffic. Driving in heavy traffic can reduce fuel economy because of frequent stops and starts. Choose routes that allow for smoother and more consistent speeds.

Remove unnecessary weight from the vehicle. Extra cargo adds strain on the engine, increasing fuel consumption. Removing unnecessary items from the trunk and passenger compartment can help improve fuel efficiency.