2018 BMW 6 Series Gran Turismo Gas Tank Size & Fuel Capacity
Fuel tank capacity
18.0gal · 68 L
The 2018 BMW 6 Series Gran Turismo has a fuel tank capacity of 18.0 gallons (68 liters).
A full tank is good for roughly 504 highway miles or 360 miles around town, going by the EPA ratings.
18.0 gal · Bigger than 50% of 2018 models we list.
Listed separately: 2018 BMW 6 Series (18.5 gal).
2018 BMW 6 Series Gran Turismo fuel tank capacity by trim
MPG and range are city / highway.
| Trim | Engine | Drive | Tank | MPG city / hwy | Range city / hwy | |
|---|---|---|---|---|---|---|
| 640i xDrive 4dr Hatchback AWD 3.0L 6cyl Turbo 8A · AWD MPG 20 / 28Range 360 / 504 mi | 3.0L 6cyl Turbo 8A | AWD | 18.0 gal68 L | 20 / 28 | 360 / 504 mi | |
| No trim matches all of these filters. | ||||||
Tank figures are the manufacturer's rated capacity, sorted smallest tank first. Range is tank size times EPA city or highway MPG.
How far a 2018 BMW 6 Series Gran Turismo goes on a tank
Gallons left and the distance they cover at each mark on the fuel gauge, at EPA city and highway mileage. At the combined rating of 23 MPG, a full 18.0-gallon tank covers about 414 miles.
| Gauge | Gallons | Highway miles | City miles |
|---|---|---|---|
| Full | 18.0 | 504 | 360 |
| 3/4 | 13.5 | 378 | 270 |
| 1/2 | 9.0 | 252 | 180 |
| 1/4 | 4.5 | 126 | 90 |
| 1/8 | 2.3 | 63 | 45 |
Over 15,000 miles a year (the EPA's yearly estimate) this configuration uses about 652 gallons, roughly 36 full tanks.
Fuel gauges aren't perfectly linear and the low-fuel light comes on with a few gallons still in the tank, so plan your stop before the last eighth.
What it costs to fill up a 2018 BMW 6 Series Gran Turismo
$95.04 to fill the 18.0-gallon tank from empty with premium, at this week's US average of $5.28 a gallon.
| Tank | Fuel | US avg / gal | From empty | From 1/4 tank |
|---|---|---|---|---|
| 18.0 gal | Premium | $5.28 | $95.04 | $71.28 |
By region, 18.0-gallon tank
| Region | Premium / gal | Fill from empty |
|---|---|---|
| East Coast | $4.93 | $88.74 |
| Midwest | $5.37 | $96.66 |
| Gulf CoastLowest | $4.57 | $82.26 |
| Rocky Mountain | $5.12 | $92.16 |
| West Coast | $6.08 | $109.44 |
| CaliforniaHighest | $6.36 | $114.48 |
Prices: U.S. Energy Information Administration retail averages for the week of October 26, 2026. This week's prices by state and city.
Your own price
- 18.0-gallon tank$95.04
- A year of driving (15,000 mi)$3,443
Starts at the US average for premium; type in what your station charges. For other tank sizes, use the fill-up calculator.
6 Series Gran Turismo tank size in other years
2018 is the first 6 Series Gran Turismo model year we list.
| Model year | Tank | Longest highway range |
|---|---|---|
| 2019 6 Series Gran Turismo | 18.0 gal | 504 mi |
| 2018 6 Series Gran Turismo | 18.0 gal | 504 mi |
Frequently asked questions
What is the fuel tank capacity of the 2018 BMW 6 Series Gran Turismo?
The 2018 BMW 6 Series Gran Turismo holds 18.0 gallons (68 liters).
How many gallons and liters does the 2018 BMW 6 Series Gran Turismo gas tank hold?
The 2018 BMW 6 Series Gran Turismo tank holds 68 liters, or 18.0 gallons in US gallons.
How far can a 2018 BMW 6 Series Gran Turismo go on a full tank?
About 504 miles on the highway and 360 miles in town, going from full to empty at its EPA ratings. Expect less in practice, since nobody runs the tank dry.
How many miles can a 2018 BMW 6 Series Gran Turismo go on a quarter tank?
About 126 highway miles or 90 in town from the 18.0-gallon tank, which has roughly 4.5 gallons left at the quarter mark. Gauges aren't exact, so treat that as a guide.
What gas does the 2018 BMW 6 Series Gran Turismo take?
Premium unleaded (recommended). The label inside the fuel door confirms it for your car.
How much does it cost to fill up a 2018 BMW 6 Series Gran Turismo?
At the US average of $5.28 a gallon for premium (EIA, week of October 26, 2026), filling the 18.0-gallon tank from empty costs $95.04. It ranges from $82.26 in the Gulf Coast to $114.48 in California.
How much does a full tank of gas weigh in a 2018 BMW 6 Series Gran Turismo?
About 112 pounds for the 18.0-gallon tank. Gasoline weighs roughly 6.2 pounds a gallon.
Sources
- Tank sizes: manufacturer-rated capacities from US-market specifications, checked against independent references. Updated October 2026.
- MPG and range: EPA ratings. Range is tank size times EPA MPG.
- Fuel prices: U.S. Energy Information Administration, week of October 26, 2026 (this week's prices).
Does your owner's manual say something different? Let us know and we'll fix it. More on how we check the numbers.