Complete BMW 8 Series Fuel Consumption, Tank Size, and Fuel Type Guide

Complete BMW 8 Series Fuel Consumption, Tank Size, and Fuel Type Guide

The BMW 8 Series is a luxury grand tourer that offers impressive performance and efficiency across its various models and generations. As a high-performance vehicle, using the proper fuel grade is crucial for maintaining optimal engine function and longevity. This comprehensive guide will cover everything you need to know about fueling your BMW 8 Series, including recommended octane ratings, fuel tank capacities, and real-world consumption figures for all variants and generations.

Recommended Fuel Grade for BMW 8 Series

BMW recommends premium unleaded gasoline for all 8 Series models to ensure peak performance and efficiency. The specific octane rating required depends on the market and engine type:

• North America: 91 AKI (Anti-Knock Index) minimum
• Europe: 95 RON (Research Octane Number) minimum
• Performance models (M850i, M8): 98 RON / 93 AKI recommended for best results

Using a lower octane fuel than recommended may result in reduced performance, lower fuel economy, and potential engine damage over time. The vehicle’s engine management system can adjust timing to accommodate lower octane fuel if necessary, but this comes at the cost of reduced power output.

Why Premium Fuel Matters for the BMW 8 Series

The high-performance engines in the BMW 8 Series are designed with higher compression ratios and more advanced technologies that benefit from premium fuel:

• Improved combustion efficiency
• Reduced risk of engine knocking
• Optimal power output
• Better fuel economy
• Lower emissions

While it’s possible to use regular unleaded fuel (87 AKI / 91 RON) in emergency situations, consistent use of lower octane fuel may lead to decreased performance and potential long-term engine issues.

Fuel Tank Capacity by BMW 8 Series Model

The fuel tank capacity varies slightly between different 8 Series models and body styles. Here’s a breakdown of tank sizes for the current generation (G14/G15/G16):

As you can see, BMW has standardized the fuel tank capacity across the 8 Series range, providing ample fuel storage for long-distance cruising.

Fuel Consumption Figures for BMW 8 Series Models

Fuel consumption varies depending on the specific engine, drivetrain configuration, and body style. Here are the official combined fuel economy figures for current 8 Series models, as reported by BMW:

840i Models (3.0L Inline-6 Turbo)

M850i xDrive Models (4.4L V8 Turbo)

M8 Models (4.4L V8 Turbo)

It’s important to note that these figures are based on standardized testing procedures and may vary in real-world driving conditions.

Real-World Fuel Consumption

Actual fuel consumption can differ significantly from official figures due to various factors such as driving style, road conditions, and climate. Here are some real-world consumption reports from BMW 8 Series owners:

840i Models

• City driving: 18-22 mpg (13.1-10.7 L/100km)
• Highway driving: 28-32 mpg (8.4-7.4 L/100km)
• Mixed driving: 23-26 mpg (10.2-9.0 L/100km)

M850i xDrive Models

• City driving: 15-18 mpg (15.7-13.1 L/100km)
• Highway driving: 23-26 mpg (10.2-9.0 L/100km)
• Mixed driving: 18-21 mpg (13.1-11.2 L/100km)

M8 Models

• City driving: 13-16 mpg (18.1-14.7 L/100km)
• Highway driving: 20-23 mpg (11.8-10.2 L/100km)
• Mixed driving: 16-19 mpg (14.7-12.4 L/100km)

These figures are based on owner reports and may vary depending on individual circumstances.

Factors Affecting Fuel Consumption

Several factors can impact the fuel efficiency of your BMW 8 Series:

Driving Style

Aggressive acceleration, high-speed driving, and frequent braking can significantly increase fuel consumption. Adopting a smoother driving style with gradual acceleration and anticipating traffic flow can help improve efficiency.

Traffic Conditions

Stop-and-go traffic in urban areas typically results in higher fuel consumption compared to steady highway cruising.

Climate and Weather

Extreme temperatures can affect fuel efficiency. Cold weather may require longer warm-up times and increase fuel consumption, while hot weather can increase the load on the air conditioning system.

Vehicle Load

Carrying extra weight or using roof racks can increase aerodynamic drag and fuel consumption.

Tire Pressure

Maintaining proper tire pressure is crucial for optimal fuel efficiency. Underinflated tires can increase rolling resistance and fuel consumption.

Maintenance

Regular maintenance, including oil changes, air filter replacements, and proper wheel alignment, can help maintain optimal fuel efficiency.

Tips for Maximizing Fuel Efficiency in Your BMW 8 Series

While the BMW 8 Series is designed for performance, there are several ways to improve fuel efficiency without sacrificing the driving experience:

1. Use the Recommended Premium Fuel

Always use the recommended premium fuel to ensure optimal engine performance and efficiency.

2. Monitor Your Driving Style

Use the on-board computer to track your fuel consumption in real-time and adjust your driving style accordingly.

3. Utilize Eco Pro Mode

The 8 Series comes equipped with an Eco Pro driving mode that optimizes various vehicle systems for improved efficiency. Use this mode when maximum performance isn’t required.

4. Plan Your Routes

Use navigation systems to plan efficient routes and avoid heavy traffic areas when possible.

5. Maintain Your Vehicle

Follow BMW’s recommended maintenance schedule to keep your 8 Series running at peak efficiency.

6. Check Tire Pressure Regularly

Ensure your tires are properly inflated to the recommended pressures.

7. Reduce Unnecessary Weight

Remove any unnecessary items from your vehicle to reduce weight and improve fuel economy.

8. Use Start-Stop Technology

The 8 Series is equipped with start-stop technology that can help reduce fuel consumption in city driving. Ensure this feature is activated unless conditions require it to be turned off.

Fuel Efficiency Comparison: BMW 8 Series vs Competitors

To put the BMW 8 Series’ fuel efficiency into perspective, let’s compare it to some of its key competitors in the luxury grand tourer segment:

As we can see, the BMW 8 Series, particularly in its 840i configuration, offers competitive fuel efficiency within its class.

Historical Perspective: Fuel Efficiency Across 8 Series Generations

The BMW 8 Series has seen significant improvements in fuel efficiency since its introduction in 1989. Let’s look at how fuel consumption has changed across generations:

First Generation (E31, 1989-1999)

• 850i/850Ci (5.0L V12): 13 mpg combined (18.1 L/100km)
• 840Ci (4.0L V8): 15 mpg combined (15.7 L/100km)

Second Generation (G15/G14/G16, 2018-present)

• 840i (3.0L I6 Turbo): 23 mpg combined (10.2 L/100km)
• M850i xDrive (4.4L V8 Turbo): 19 mpg combined (12.4 L/100km)

These figures demonstrate the significant advancements in engine technology and efficiency over the past three decades, with modern 8 Series models offering substantially improved fuel economy despite increased performance capabilities.

Future of Fuel Efficiency in the BMW 8 Series

As automotive technology continues to evolve, we can expect future iterations of the BMW 8 Series to offer even greater fuel efficiency without compromising performance. Some potential developments include:

Mild Hybrid Systems

BMW has already introduced 48V mild hybrid technology in some models, which could be expanded to the entire 8 Series range to improve efficiency, especially in urban driving scenarios.

Plug-in Hybrid Variants

While not currently offered, a plug-in hybrid version of the 8 Series could provide significant improvements in fuel efficiency for short to medium-distance trips.

Advanced Materials

BMW continues to invest in lightweight materials such as carbon fiber reinforced plastic (CFRP) and aluminum. Future 8 Series models may incorporate more of these materials to reduce overall vehicle weight, thereby improving fuel efficiency without sacrificing structural integrity or performance.

Aerodynamic Improvements

Further refinements in aerodynamics could help reduce drag and improve fuel economy, especially at higher speeds. This might include active aerodynamic elements that adjust based on driving conditions.

Next-Generation Engines

BMW is likely to continue developing more efficient internal combustion engines, potentially with higher compression ratios and more advanced fuel injection systems, leading to improved fuel economy across the range.

Electric Variants

As BMW expands its electric vehicle lineup, we may see an all-electric version of the 8 Series in the future, offering zero emissions and potentially lower operating costs.

Understanding Fuel Consumption Ratings

To better interpret the fuel consumption figures for the BMW 8 Series, it’s important to understand how these ratings are determined and what they mean in practical terms.

EPA Ratings (United States)

In the United States, fuel economy is rated by the Environmental Protection Agency (EPA) using a standardized testing procedure. The ratings are expressed in miles per gallon (mpg) and typically include:

• City MPG: Simulates urban driving with frequent stops
• Highway MPG: Simulates steady, higher-speed driving
• Combined MPG: A weighted average of city (55%) and highway (45%) driving

These ratings are designed to provide a standardized comparison between different vehicles but may not accurately reflect real-world fuel consumption for all drivers.

WLTP Ratings (Europe)

In Europe and many other markets, fuel consumption is rated using the Worldwide Harmonised Light Vehicle Test Procedure (WLTP). This test aims to provide more realistic consumption figures and is expressed in liters per 100 kilometers (L/100km). The WLTP test includes:

• Low speed urban driving
• Medium speed suburban driving
• High speed rural driving
• Extra high speed motorway driving

WLTP ratings tend to be closer to real-world consumption figures than the previous NEDC (New European Driving Cycle) ratings, but individual results may still vary.

Fuel Costs and the BMW 8 Series

When considering the overall cost of ownership for a BMW 8 Series, fuel costs play a significant role. Here’s a breakdown of potential annual fuel costs based on different models and driving scenarios:

*Based on an average premium fuel price of $3.50 per gallon. Actual costs may vary depending on local fuel prices and individual driving patterns.

Factors Affecting Fuel Costs

• Local fuel prices
• Driving habits and conditions
• Maintenance status of the vehicle
• Use of features like air conditioning and heated seats
• Traffic conditions in your area

Environmental Impact and Emissions

While fuel consumption is closely tied to operating costs, it’s also important to consider the environmental impact of the BMW 8 Series. Here’s an overview of emissions data for current models:

CO2 Emissions

BMW continues to work on reducing emissions across its lineup, including the 8 Series, through advancements in engine technology and the introduction of electrified powertrains.

Emission Standards Compliance

All current BMW 8 Series models comply with the latest emission standards, including:

• Euro 6d in Europe
• EPA Tier 3 in the United States
• LEV III in California and states following California standards

These standards ensure that the 8 Series meets strict requirements for emissions of pollutants such as nitrogen oxides (NOx), carbon monoxide (CO), and particulate matter.

Alternative Fuel Options for the BMW 8 Series

While the current BMW 8 Series lineup is primarily focused on gasoline engines, there’s growing interest in alternative fuel options. Here’s a look at potential future developments and current alternatives:

Hydrogen Fuel Cell Technology

BMW has been experimenting with hydrogen fuel cell technology, which could potentially be applied to larger vehicles like the 8 Series in the future. Benefits of hydrogen fuel cell vehicles include:

• Zero emissions (only water vapor as a byproduct)
• Quick refueling times comparable to gasoline vehicles
• Long driving ranges

However, challenges such as limited hydrogen infrastructure and high production costs need to be addressed before this technology becomes viable for mainstream models.

Synthetic Fuels

BMW, along with other German automakers, has shown interest in synthetic fuels (e-fuels) as a potential way to reduce the carbon footprint of internal combustion engines. These fuels are produced using renewable energy and could potentially be used in existing 8 Series models with minimal modifications.

Biodiesel Compatibility

While not officially recommended by BMW for the 8 Series, some diesel engines in other BMW models are compatible with biodiesel blends. If BMW were to introduce a diesel variant of the 8 Series in the future, it might be designed to accommodate biodiesel fuels, offering a more environmentally friendly option for diesel enthusiasts.

Fuel System Maintenance for the BMW 8 Series

Proper maintenance of the fuel system is crucial for ensuring optimal performance, efficiency, and longevity of your BMW 8 Series. Here are some key maintenance aspects to consider:

Fuel Injector Cleaning

Over time, fuel injectors can become clogged with deposits, leading to reduced efficiency and performance. BMW recommends using Top Tier detergent gasoline to help keep injectors clean. Additionally, professional fuel injector cleaning may be beneficial every 60,000 to 90,000 miles.

Fuel Filter Replacement

The fuel filter helps remove contaminants from the fuel before it reaches the engine. BMW typically recommends replacing the fuel filter every 60,000 miles, but this can vary depending on fuel quality and driving conditions.

Fuel Pump Maintenance

The high-pressure fuel pump in modern BMW engines is a critical component. While it doesn’t require regular maintenance, it’s important to address any warning signs of fuel pump issues promptly, such as difficulty starting the engine or loss of power.

Using Fuel Additives

While not typically necessary when using high-quality fuel, some owners choose to use fuel additives to help clean the fuel system and improve performance. If considering fuel additives, it’s important to use products specifically approved for use in BMW engines.

Fuel-Related Features in the BMW 8 Series

The BMW 8 Series incorporates several features designed to optimize fuel usage and enhance the overall driving experience:

Auto Start-Stop Function

This feature automatically shuts off the engine when the vehicle comes to a stop (e.g., at traffic lights) and restarts it when the brake is released. It can help reduce fuel consumption and emissions, particularly in urban driving scenarios.

Brake Energy Regeneration

This system harnesses kinetic energy during braking and deceleration, converting it into electrical energy to charge the vehicle’s battery. This reduces the load on the alternator, slightly improving fuel efficiency.

Adaptive Cruise Control with Eco Function

The advanced cruise control system in the 8 Series includes an eco function that can adjust the vehicle’s speed based on the road ahead, optimizing fuel consumption during long-distance driving.

Driving Experience Control

This feature allows drivers to select different driving modes, including an Eco Pro mode that adjusts various vehicle systems to maximize efficiency. In Eco Pro mode, the 8 Series may:

• Optimize throttle response for efficiency
• Adjust transmission shift points
• Limit power to auxiliary systems like climate control
• Provide coaching tips for more efficient driving

Fuel Tank Design and Safety Features

The fuel tank in the BMW 8 Series is designed with both performance and safety in mind. Here are some key aspects of the fuel tank design:

Tank Construction

The fuel tank is typically made from high-density polyethylene (HDPE), which offers several advantages:

• Lightweight, contributing to overall vehicle efficiency
• Corrosion-resistant
• Durable and impact-resistant
• Can be molded into complex shapes to maximize capacity and fit

Safety Features

The 8 Series fuel system incorporates several safety features:

• Anti-siphon device to prevent fuel theft
• Rollover valves to prevent fuel leakage in case of a rollover accident
• Fuel pump shut-off in case of a collision
• Reinforced mounting points to secure the tank in impacts

Fuel Level Sensor

The 8 Series uses a sophisticated fuel level sensor that provides accurate readings to the driver. This helps prevent running out of fuel and allows for more precise fuel economy calculations.

Refueling the BMW 8 Series

Proper refueling practices can help maintain the efficiency and performance of your BMW 8 Series. Here are some tips and information about the refueling process:

Locating the Fuel Filler

The fuel filler cap is located on the right side of the vehicle. It can be opened by pressing the rear edge of the fuel filler flap when the vehicle is unlocked.

Capless Fuel Filler System

Many recent 8 Series models feature a capless fuel filler system, which automatically opens when the fuel nozzle is inserted and seals when it’s removed. This system helps prevent fuel vapors from escaping and reduces the risk of using the wrong type of fuel.

Refueling Tips

• Always use the recommended grade of premium unleaded gasoline
• Avoid overfilling the tank, as this can damage the emissions system
• If you hear a click or the pump stops, the tank is full – don’t try to add more
• Avoid spilling fuel on the vehicle’s paintwork, as it can cause damage

Emergency Refueling

In case you run out of fuel, the 8 Series is equipped with an emergency fuel filler funnel located in the toolkit. This allows for safe refueling from a gas can if necessary.

Fuel Economy Display and Trip Computer

The BMW 8 Series provides drivers with detailed information about fuel consumption through its advanced instrument cluster and iDrive infotainment system. Here’s an overview of the fuel-related information available:

Real-Time Fuel Economy

The instrument cluster displays real-time fuel economy, allowing drivers to adjust their driving style for better efficiency.

Average Fuel Consumption

The trip computer calculates average fuel consumption over different periods:

• Since last refueling
• Since start of journey
• Long-term average

Range Prediction

Based on current fuel level and recent consumption patterns, the system provides an estimated driving range.

Eco Pro Feedback

When driving in Eco Pro mode, the system provides feedback on efficient driving techniques and displays potential fuel savings.

Conclusion: Balancing Performance and Efficiency in the BMW 8 Series

The BMW 8 Series represents a pinnacle of automotive engineering, blending high performance with relatively efficient operation for its class. While fuel consumption may not be the primary concern for many 8 Series buyers, BMW has made significant strides in improving efficiency without compromising the driving experience that defines the brand.

Key takeaways about fuel use in the BMW 8 Series include:

• Premium fuel (91 AKI / 95 RON minimum) is required for optimal performance and efficiency
• Fuel tank capacity is standardized at 68 liters (18 gallons) across the range
• Real-world fuel consumption can vary significantly from official figures, influenced by driving style and conditions
• Modern 8 Series models offer substantially improved fuel economy compared to their predecessors
• Future developments may include mild hybrid systems, plug-in hybrids, and potentially all-electric variants

For 8 Series owners and potential buyers, understanding the fuel requirements and consumption characteristics of these vehicles is crucial for both budgeting and environmental considerations. By following recommended maintenance procedures, adopting efficient driving techniques, and staying informed about technological advancements, 8 Series drivers can maximize the efficiency of their vehicles while enjoying the unparalleled performance and luxury that BMW offers.

As automotive technology continues to evolve, we can expect future iterations of the 8 Series to push the boundaries of performance and efficiency even further, ensuring that this iconic model remains at the forefront of the luxury grand tourer segment for years to come.