BMW 4 series vs 3 series

The BMW 3 series has built itself a reputation as a luxury sedan. As BMW continued been innovative and serving a diverse client base there was a need to create a luxury coupe that resembles the 3 series. This is where the BMW 4 series serves well. It is a two door coupe but with a more powerful engine. It can be confusing choosing between the two and that is why we have this review. We are going to be putting the BMW 3 side by side against the 4 series.

What are the key differences between the BMW 4 series and 3 series

BMW 4 series (M440i xDrive)
3 series (M340i)
382HP @6500rpm
382HP @6500rpm
Fuel efficiency
24mpg city/34 highway
31mpg city/43mpg highway
Body styles
Coupe, gran coupe, and convertible
Sports sedan, sports wagon, and gran turismo
Engine type
Turbocharged and Intercooled DOHC 24-valve
Turbocharged and intercooled DOHC 22-valve
8-speed automatic
Wheel base
Passenger volume
87 cubic feet
95 cubic feet
188” L, 72.9”W, 54.8”H
185.7” L, 71.9”W, 56.4”H

BMW 4 series vs. 3 series – How do they compare?

Body designs

One key difference between this two is that the BMW 3 series is offered as a sports sedan, wagon, and Gran Turismo. The 4 series is offered as coupe, grand coupe and convertible model. The cars have different options hence meeting a wide range of customer needs. We can conclude that you have more body style options in the 3 series than the 4 series. The 3 series is also more spacious hence making it an ideal sedan for family setups. The 4 series is more sporty and may be more suitable for those looking for something classy and aggressive.

When the two motor vehicles were introduced the 3 series was a sedan with four doors while the 4 series was a coupe with two doors, however, the lines have become blurred with the 4 series introducing the Gran coupe which is a four door car.


Both cars come with 2.0 liter turbocharged 1-4 engines but the performance is different. The BMW 4 series has both the same 255HP engine like the 3-series but also a more powerful 382HP in-line six engine. When it comes to gas mileage you get almost the same figures with the 3 series delivering 35mpg on the highway and the 4 series delivering 34mpg. This gives you average mileage of 23mpg for the city. If you are in need of more power you can try out the 3.0 liter twin-turbo version. With this car you are capable of achieving an output of 382 horsepower and this allows you to move from 0 to 60mph in 4.6 seconds.

Accessories and Interior

While most of the interior features are almost similar they are some subtle differences. For example, the 3 series comes with a full color head-up display that is optional in the 4-series. With the display you can drive without removing your eyes from the road. In the 4-series you have a sun/moon roof as standard while this is optional in the 3-series. There are some cool features in the 4-series that you will not find in the 3-series like active driving assistant, active blind spot detection and active cruise control. In this round we will conclude that the interior of the 4-series is a bit cooler than that of the 3-series.

BMW 4 series vs. 3 series – How do they compare?

BMW 3 series – Overview

The BMW M340i is a powerful German machine that is capable of delivering 382 horsepower @6,500 rpm. It is linked via an eight speed automatic transmission and this enables it to get from 0 to 60 seconds in 3.8 seconds. You can get the 3-series in either the 255HP four-cylinder engine or the massive 382HP six cylinder. The difference on the road is quite distinct. For those who are into green energy, BMW has a plug-in hybrid 3-series. What has really changed about the 3-series is that BMW ditched its usual manual transmission for an eight-speed transmission.

The hybrid 3-series model has had some improvements for the 2021 version. You now get a top speed on the 330e of 87mph on all electric mode up from 75mph. The battery is also larger at 12kwh against the previous 7.6kwh. But, if you are looking for speed nothing beats the M340i in the 3-series line of vehicles. But, you pay more for it. The 330e is available in a 2.0 liter turbocharged engine that generates 288 worth of horsepower. The car comes with a special Xtraboost functionality that operates like nitrous and gives you that extra dash of power. The car is a rear wheel drive and is linked via an eight-speed transmission.

When it comes to fuel economy the 3-series performs well with delivering 26mpg in the city and 36mpg on highways. If you opt for the M340i you are getting 23mpg in the city and 32 on highways. The 330e which is the hybrid version gives you a mileage of 28mpg and when in all electric mode 23 miles.

The 3-series interior is a work of art and it does deliver in terms of luxury features. The standard sport seats are supportive and well-bolstered. You can pay more for a detailed head-up display, heated front and rear seats, customized ambient interior lighting, wireless charging and remote start. At the back you do have significant storage space of 17 cubic feet.

What we liked:

  • Generous cabin space
  • Roomy interior
  • First-rate powertrains
  • Superfast M-version

What we did not like:

BMW has stopped production of manual transmission

BMW 4 series – Overview

When the 4-series was introduced it looked similar to the 3-series but it was more of a coupe. The car was mainly two door but BMW have introduced another version the Gran Coupe which is a four door car. Now you have versions – the coupe, Gran coupe and convertible model. At close inspection the 4-series distinguishes itself from the 3-series with its elegant roofline and enhanced front end design.

It is powered by two powertrains. You have the 255HP turbo four-cylinder engine similar to the 3-series and you have the massive 382HP turbocharged in-line six. The passenger space for the two door series is arranged a bit differently than what you would find in a four door sedan but it is still spacious. You also get all the latest gadgets you will normally find in any BMW car.

When it comes to the 4 series our top choice would be its M440i. While you do pay higher you do get some additional features like it being all-wheel drive and the fact you get these cool M sport 18” wheels. The tires are run flat. The suspension on the M sport version is also a bit different from the others. It includes a rear spoiler and faux leathered wrapped dashboard.

In the 4-series you get some of the same engine varieties like the 3-series. You have the M430i that has a 255HP 2.0 liter turbocharged engine and the M440i that has the larger 3.0 liter in-line six engine that gives you an output of 382 horsepower. The 4 series is a bit sporty and it is for those who are excited about more power. When it comes to fuel efficiency you get 26mpg on the city and 34mpg on the highway for the M430i. If you are doing all-wheel drive then the figures change to 24mpg for the city and 33mpg for highways.

There is little difference between the 4-series interior and 3-series besides the lack of space for the back seat. All the other materials like the dashboard, interior materials and layout is similar. The 4-series has lower roofline which eats up some space. The trunk is also less spacious like the 3-series but it still can handle up to five carry-on suitcases. For the infotainment screen you get the standard 8.8” screen with the option of a 10.3 inch screen. On board you have the latest BMW iDrive 7 software and this makes the screen more intuitive. You get Android Auto, Apple CarPlay and in-dash navigation.

What we liked:

  • Car has a sporty feel
  • Good on fuel economy
  • Powerful turbocharged engines
  • Luxurious cabins

What we did not like:

The front grille is not that stylish

Verdict: So, which is better – BMW 3-series or 4-series?

If you have a family and are in need of trunk space then we would recommend you go with the 3-series. The car is roomy while still being sporty. However, if all you want is a stylish BMW that is also fast then the 4-series is something you would want to try out.


Which one offers more trunk space the 3-series or 4-series?

If you are looking for a spacious car then the 3-series outperforms the 4-series in this category

Is the 4-series a fuel guzzler?

Not really, it is quite modest when it comes to fuel consumption, you should expect to 22mpg on city drives and 31 mpg on highways

Jurgen Shmidt works as an automotive engineer, his duties revolve around vehicle design, development manufacture, and testing. Shmidt is also involved in marketing, sales, and the after-sale care of cars, apart from his 8 hours job, he interacts with enthusiasts who have concerns or wish to learn about the various models of the BMW luxury cars. Shmidt believes that the demand for detailed information surpasses its availability and that is why he dedicates most of his free time, researching and compiling reliable information. The information compiled on bmwexpert has been derived from hands-on experience and not some snazzy press release, thus we believe you will find answers to your troubling questions about the BMW.

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