Buying Guide

2015 BMW 6-Series

Fair Market Price $45,823 640 i Convertible
Motor Trend Rating


21 City / 32 Hwy

Horse Power:

315 @ 5800


330 @ 1400

New for 2015

The 2015 BMW 6 Series line gets minor changes and the Alpina B6 xDrive Gran Coupe is introduced — a milestone because BMW’s own M division doesn’t (yet) offer all-wheel-drive cars with lots of power. The 6 Series sees minor changes for the 2016 model year.

Vehicle Overview

The BMW 6 Series comes in coupe, coupe-like four-door (Gran Coupe), and convertible forms, fitting above the 4 Series coupe, convertible, and four-door hatchback as the automaker’s most expensive two-doors underneath the i8 supercar.


The 2015 BMW 6 Series is powered by a quartet of engines, each with its intended audience or niche. From the attractive Coupe, to the fun convertible, to the versatile Gran Coupe coupe-like four-door, all the way to M6-based models, and even further to high performance Alpina B6 xDrive Gran Coupe.

Model: 640i/640ixDrive in coupe, convertible, and Gran Coupe forms

Engine and Transmission: Turbocharged 3.0-liter I-6 – eight-speed auto

Power: 315 hp/330 lb-ft

EPA-rated fuel efficiency: 21/32 mpg (coupe) – 20/29 mpg (all three variants with xDrive ) – 20/31 mpg (convertible, Gran Coupe)

Model: 650i/650i xDrive in coupe, convertible, and Gran Coupe forms

Engine and Transmission: Twin-turbocharged 4.4-liter V-8 – eight-speed auto

Power: 445 hp/480 lb-ft

EPA-rated fuel efficiency: 17/25 mpg (coupe, convertible, Gran Coupe) – 16/25 mpg (coupe xDrive) – 16/24 mpg (convertible and Gran Coupe with xDrive)

Model: M6, M6 Convertible, M6 Gran Coupe

Engine and Transmission: Twin-turbocharged 4.4-liter V-8 – seven-speed auto or six-speed manual

Power: 560 hp/500 lb-ft

EPA-rated fuel efficiency: 14/20 mpg (seven-speed auto) – 15/22 mpg (six-speed manual)

Model: Alpina B6 xDrive Gran Coupe

Engine and Transmission(s): Twin-turbocharged 4.4-liter V-8 – eight-speed auto

Power: 540 hp/540 lb-ft

EPA-rated fuel efficiency: 16/24 mpg

Some of the most notable features on the 2015 6 Series include LED headlights, active blind spot detection, full color head-up display, lane departure warning, pedestrian & collision warnings, a Bang & Olufsen premium audio system, an available night vision system that aids in pedestrian/animal detection, and a parking assistance system that will steer the 6 into a parallel space.

The 2015 BMW 6 Series has not been evaluated by the NHTSA or the IIHS.

What We Think

The 2015 BMW 6 Series comes in coupe, convertible, or coupe-like four-door forms, and seeks to provide a balance between sport and luxury. Much like the 8 Series from years past, the 6 Series is a lavishly appointed two-door touring car that is as comfortable at 150 mph as it is around town. The interior appointments set the bar for BMW interiors, and we noted in an Editor’s Notebook review of a 2012 650i Coupe that “all the materials look and feel expensive,” something you would hope was present in a vehicle whose price can crest $100,000. One downside to the 6 Series, indeed many BMW models, is the way they can get pricey in a hurry with options.

We suggest passing on the turbocharged 3.0-liter I-6 (640i models) on account of the performance, as we noted in a Driven review of a 2014 640i Gran Coupe, “Its 315-hp, 3.0-liter turbocharged I-6 is powerful enough, but the 640i Gran Coupe lacks any real urgency or excitement.” Opting for any variant of the twin-turbo V-8 solves that problem (650i, M6, Alpina B6), as in an Editor’s Notebook review of a 2012 M6 Convertible we said, “[the M6 Convertible] feels like a (recent) BMW M car: an otherwise heavy car that bends physics and delights passengers.”

Speaking of passengers, the M6 Gran Coupe is a more stylish M5, but with a much improved interior for four. In our Driven review of a 2014 M6 Gran Coupe at the Circuit of the Americas in Texas, we noted that “it will lap racetracks faster than any other BMW production car, including the vaunted M3.” The Alpina B6 xDrive Gran Coupe is the best of the 6 Series bunch if touring is your aim, and as we noted in a Driven review of a 2015 Alpina B6 xDrive Gran Coupe, “It’s more refined and sensible than the M6, and makes the regular 6 Gran Sport seem downright frumpy.”

6 Series Gran Coupe and M6 Gran Coupe compete with the Audi A7 and Mercedes Benz CLS-Class (and their high-performance variants); all vehicles that overlap their four-door platform mates but deliver “decked-out interiors,” sloping rooflines, and that coupe-like four-door look. Does the 6 Series make financial sense over a similarly-equipped 5 Series? No, but as with other popular coupe-like four-door luxury cars, style is the name of the game, something the 6 Series line does well.

You’ll Like

  • Alpina B6 for high-speed touring
  • Performance of twin-turbo V-8 models
  • Lavish interior appointments

You Won’t Like

  • Can get really pricey, really quickly
  • 20-inch wheels cause rough ride over less-than-perfect pavement
  • Getting speeding tickets

Key Competitors

  • Audi A7
  • Audi A5
  • Mercedes Benz CLS-Class
  • Mercedes Benz E-Class Coupe
  • Jaguar XF



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