2018 BMW 340i
The 2018 BMW 340i is a sedan. It has a 3.0-litre turbocharged six-cylinder engine producing 320 hp (239 kW), with an 8-speed automatic and rear-wheel drive. 0–60 mph takes 5.8 seconds and top speed is 155 mph (249 km/h).
ABOUT THE 2018 BMW 340I
The 2018 BMW 340i is the six-cylinder flagship of the regular sixth-generation 3 Series saloon (F30), sitting below only the M3. It uses BMW’s B58 3.0-litre turbocharged inline-six, rated at 320 hp and 330 lb-ft, and drives the rear wheels. This entry covers the version with the eight-speed automatic; a six-speed manual was also offered on the rear-drive car.
A strong engine in its final year
The 340i replaced the long-running 335i when the F30 was facelifted, bringing the new modular B58 engine in place of the older N55. For 2018, the last full model year before the G20 generation arrived, the 340i represented the most refined and powerful form of the F30 short of the M3, and it is widely seen as the sweet spot of the range for keen drivers.
What it is like
The inline-six is smooth and responsive, with a broad spread of torque that makes the car feel brisk at any speed. With the rear-wheel-drive layout and well-weighted controls, the 340i balances everyday comfort with genuine sports-saloon ability, and the boot and rear seat are as practical as any other F30.
Buying one today
The B58 has a good reputation overall. Items commonly reported include coolant leaks, particularly from the expansion tank and associated hoses, and oil leaks from gaskets on higher-mileage cars. Look for documented oil changes and check for worn tyres and brakes, which are expensive on performance-oriented cars.
Rivals
In 2018 the 340i faced the Audi S4, Mercedes-AMG C43, Infiniti Q50 Red Sport 400, Lexus IS 350 and Cadillac ATS 3.6.
Written by CarDetails.org. Last reviewed October 31, 2026.
SPECS
| Make | BMW | Model | 340i |
|---|---|---|---|
| Year | 2018 | Version / Trim | BMW 2018 340i |
| Body Style | Sedan | Doors | 4 |
| Seats | 5 | Ext. Colour | Alpine White, Jet Black, Black Sapphire Metallic, Mineral White Metallic, Mineral Gray Metallic, Glacier Silver Metallic, Carbon Black Metallic, Mediterranean Blue Metallic, Estoril Blue Metallic, Melbourne Red Metallic, Sunset Orange Metallic |
| Steering | LHD / RHD | Manufactured In | Germany |
| Drive | Rear-Wheel Drive (RWD) | Transmission | Automatic (S8) |
| Engine | 3.0L 6-cyl Turbo | Engine Size | 3,000 cc |
| Power | 320 hp / 239 kW | Torque | 450 Nm / 330 lb-ft |
| 0–60 mph (0–97 km/h) | 5.8 sec | Top Speed | 155 mph (249 km/h) |
| Fuel Economy | 21 mpg city / 32 mpg hwy | ||
| Wheelbase | 2,810 mm | Kerb Weight | 1,610 kg (3,549 lb) |
HOW IT COMPARES WITH OTHER 2018 SEDANS
Compared with other 2018 sedans in our database, its 320 hp is 13% more than the average 2018 sedan (284 hp), and it reaches 60 mph 0.4 seconds quicker than average.
| 2018 BMW 340i | Average 2018 sedans | Difference | |
|---|---|---|---|
| Power | 320 hp | 284 hp (92 cars) | +13% |
| Torque | 450 Nm | 391 Nm (92 cars) | +15% |
| 0–60 mph | 5.8 s | 6.2 s (93 cars) | -6% |
| Top speed | 155 mph | 141 mph (93 cars) | +10% |
| Kerb weight | 1,610 kg | 1,617 kg (100 cars) | — |
| Engine size | 3,000 cc | 2,556 cc (89 cars) | +17% |
Averages are calculated from all cars of the same model year and body type in the CarDetails.org database that have the figure listed. For 0–60 mph, a negative difference means quicker.
CLOSEST RIVALS
Other 2018 sedans with similar power to the 2018 BMW 340i.
| Car | Power | 0–60 mph | Kerb weight |
|---|---|---|---|
| 2018 BMW 340i | 320 hp | 5.8 s | 1,610 kg |
| 2018 Audi A7 quattro | 333 hp | 5.6 s | 1,820 kg |
| 2018 Subaru WRX STI Type RA | 305 hp | 4.6 s | 1,470 kg |
| 2018 Toyota Avalon | 268 hp | 7.0 s | 1,615 kg |
| 2018 Tesla Model 3 Long Range | 258 hp | 4.2 s | 1,752 kg |