2018 Mercedes-Benz GLC-Class Gas Tank Size & Fuel Capacity
Fuel tank capacity
13.2–17.4gal · 50–66 L
The 2018 Mercedes-Benz GLC-Class has a fuel tank capacity of 13.2 to 17.4 gallons (50–66 liters), depending on the trim. The most common size is 17.4 gallons, used on 4 trims.
A full tank is good for roughly 356–487 highway miles or 278–383 miles around town, going by the EPA ratings.
17.4 gal · Smaller than 55% of 2018 models we list.
Listed separately: 2018 Mercedes-Benz GLC-Class Coupe (17.4 gal).
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2018 Mercedes-Benz GLC-Class fuel tank capacity by trim
What changes the tank sizeTap an option to filter the table
- Powertrain
- Drive
- Engine
All 5 trims
MPG and range are city / highway.
| Trim | Engine | Drive | Tank | Fuel | MPG city / hwy | Range city / hwy |
|---|---|---|---|---|---|---|
| GLC 350e 4MATIC 4dr SUV AWD 2.0L 4cyl Turbo 7A · AWD · Premium (required) Plug-in hybrid MPG 24 / 27Range 317 / 356 mi | 2.0L 4cyl Turbo 7A Plug-in hybrid | AWD | 13.2 gal50 L | Premiumrequired | 24 / 27 | 317 / 356 mi |
| AMG GLC 43 4dr SUV AWD 3.0L 6cyl Turbo 9A · AWD · Premium (required) MPG 18 / 24Range 313 / 418 mi | 3.0L 6cyl Turbo 9A | AWD | 17.4 gal66 L | Premiumrequired | 18 / 24 | 313 / 418 mi |
| AMG GLC 63 4dr SUV AWD 4.0L 8cyl Turbo 9A · AWD · Premium (required) MPG 16 / 22Range 278 / 383 mi | 4.0L 8cyl Turbo 9A | AWD | 17.4 gal66 L | Premiumrequired | 16 / 22 | 278 / 383 mi |
| GLC 300 4MATIC 4dr SUV AWD 2.0L 4cyl Turbo 9A · AWD · Premium (recommended) MPG 21 / 28Range 365 / 487 mi | 2.0L 4cyl Turbo 9A | AWD | 17.4 gal66 L | Premiumrecommended | 21 / 28 | 365 / 487 mi |
| GLC 300 4dr SUV 2.0L 4cyl Turbo 9A · RWD · Premium (recommended) MPG 22 / 28Range 383 / 487 mi | 2.0L 4cyl Turbo 9A | RWD | 17.4 gal66 L | Premiumrecommended | 22 / 28 | 383 / 487 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 (worked out from the rated MPG where the EPA range wasn't published).
How far a 2018 Mercedes-Benz GLC-Class 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 24 MPG, a full 17.4-gallon tank covers about 418 miles.
| Gauge | Gallons | Highway miles | City miles |
|---|---|---|---|
| Full | 17.4 | 487 | 365 |
| 3/4 | 13.1 | 365 | 274 |
| 1/2 | 8.7 | 244 | 183 |
| 1/4 | 4.4 | 122 | 91 |
| 1/8 | 2.2 | 61 | 46 |
Over 15,000 miles a year (the EPA's yearly estimate) this configuration uses about 625 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.
- EPA combined
- 18–25 MPG
- Tailpipe CO2
- 235–479 g/mi
- EPA greenhouse score
- 3–9 of 10
- Source
- EPA ratings
What it costs to fill up a 2018 Mercedes-Benz GLC-Class
$91.87 to fill the 17.4-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 |
|---|---|---|---|---|
| 13.2 gal | Premium | $5.28 | $69.70 | $52.27 |
| 17.4 gal | Premium | $5.28 | $91.87 | $68.90 |
By region, 17.4-gallon tank
| Region | Premium / gal | Fill from empty |
|---|---|---|
| East Coast | $4.93 | $85.78 |
| Midwest | $5.37 | $93.44 |
| Gulf CoastLowest | $4.57 | $79.52 |
| Rocky Mountain | $5.12 | $89.09 |
| West Coast | $6.08 | $105.79 |
| CaliforniaHighest | $6.36 | $110.66 |
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
- 13.2-gallon tank$69.70
- 17.4-gallon tank$91.87
- A year of driving (15,000 mi)$3,300
Starts at the US average for premium; type in what your station charges. For other tank sizes, use the fill-up calculator.
GLC-Class tank size in other years
The tank changed for 2018: 13.2–17.4 gal, down from 17.4 gal on the 2017 GLC-Class.
| Model year | Tank | Longest highway range |
|---|---|---|
| 2023 GLC-Class | 17.4 gal | 539 mi |
| 2022 GLC-Class | 17.4 gal | 505 mi |
| 2021 GLC-Class | 17.4 gal | 505 mi |
| 2020 GLC-Class | 17.4 gal | 505 mi |
| 2019 GLC-Class | 13.2–17.4 gal | 470 mi |
| 2018 GLC-Class | 13.2–17.4 gal | 487 mi |
| 2017 GLC-Class | 17.4 gal | 487 mi |
2018 Mercedes-Benz GLC-Class vs similar 2018 SUVs
At 17.4 gallons, the GLC-Class's largest tank ranks fifth of the seven 2018 SUVs compared here. The Porsche Macan carries the most (19.8 gal) and the Lexus NX 300h the least (14.8 gal).
| 2018 model | Tank | Longest highway range |
|---|---|---|
| Porsche Macan | 19.8 gal | 495 mi |
| Audi Q5 | 18.5 gal | 500 mi |
| Land Rover Discovery Sport | 18.0 gal | 450 mi |
| BMW X4 | 17.7 gal | 496 mi |
| Mercedes-Benz GLC-Class | 13.2–17.4 gal | 487 mi |
| Alfa Romeo Stelvio | 16.9 gal | 473 mi |
| Lexus NX 300h | 14.8 gal | 444 mi |
Other 2018 SUVs of a similar size, one model per brand.
2018 Mercedes-Benz GLC-Class fuel system recalls
None of the 15 recalls NHTSA lists for the 2018 Mercedes-Benz GLC-Class involve the fuel system.
Frequently asked questions
What is the fuel tank capacity of the 2018 Mercedes-Benz GLC-Class?
The 2018 Mercedes-Benz GLC-Class holds between 13.2 and 17.4 gallons, depending on the trim. 17.4 gallons is the usual size; the smaller 13.2-gallon tank is on the GLC 350e 4MATIC 4dr SUV AWD.
How many gallons and liters does the 2018 Mercedes-Benz GLC-Class gas tank hold?
The 2018 Mercedes-Benz GLC-Class tank holds 50–66 liters, or 13.2–17.4 gallons in US gallons.
Which 2018 Mercedes-Benz GLC-Class has the biggest gas tank?
The 17.4-gallon tank is on the AMG GLC 43 4dr SUV AWD, AMG GLC 63 4dr SUV AWD, GLC 300 4MATIC 4dr SUV AWD and 1 other trim. The smallest tank, 13.2 gallons, is on the GLC 350e 4MATIC 4dr SUV AWD.
Does the 2018 Mercedes-Benz GLC-Class tank change with the powertrain?
Yes. Plug-in hybrid: 13.2 gal; Gas: 17.4 gal.
Does AWD change the 2018 Mercedes-Benz GLC-Class gas tank?
Yes. AWD: 13.2–17.4 gal; RWD: 17.4 gal.
How far can a 2018 Mercedes-Benz GLC-Class go on a full tank?
About 356–487 miles on the highway and 278–383 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 Mercedes-Benz GLC-Class go on a quarter tank?
About 122 highway miles or 91 in town from the 17.4-gallon tank, which has roughly 4.4 gallons left at the quarter mark. Gauges aren't exact, so treat that as a guide.
What gas does the 2018 Mercedes-Benz GLC-Class take?
Premium unleaded (required), or Premium unleaded (recommended), depending on the engine. The label inside the fuel door confirms it for your car.
How much does it cost to fill up a 2018 Mercedes-Benz GLC-Class?
At the US average of $5.28 a gallon for premium (EIA, week of October 26, 2026), filling the 17.4-gallon tank from empty costs $91.87. It ranges from $79.52 in the Gulf Coast to $110.66 in California.
How much does a full tank of gas weigh in a 2018 Mercedes-Benz GLC-Class?
About 108 pounds for the 17.4-gallon tank. Gasoline weighs roughly 6.2 pounds a gallon.
Does the 2018 Mercedes-Benz GLC-Class have a bigger gas tank than the Lexus NX 300h?
Yes. The 2018 Mercedes-Benz GLC-Class holds up to 17.4 gallons; the 2018 Lexus NX 300h holds up to 14.8.
Has the 2018 Mercedes-Benz GLC-Class had a fuel pump or fuel system recall?
No. None of the 15 recalls NHTSA lists for the 2018 Mercedes-Benz GLC-Class involve the fuel system.
Sources
- Tank sizes: manufacturer-rated capacities from US-market specifications, checked against independent references. Updated October 2026.
- MPG and range: EPA ratings (fueleconomy.gov). Range is tank size times EPA MPG.
- Fuel prices: U.S. Energy Information Administration, week of October 26, 2026 (this week's prices).
- Recalls: NHTSA recall database (Mercedes-Benz fuel system recalls).
Does your owner's manual say something different? Let us know and we'll fix it. More on how we check the numbers.