2018 BMW 6 Series Convertible

2018 BMW 6 Series Convertible 640i xDrive Convertible

All BMW 6 Series Convertible F12 trims (2012–2018) → All BMW 6 Series Convertible generations →

The 2018 BMW 6 Series Convertible 640i xDrive Convertible is a 315-hp 3.0-liter turbocharged inline-6 convertible with an 8-speed automatic and all-wheel drive. It starts at $89,700 MSRP.

It makes 315 horsepower and 330 lb-ft of torque.

The 6 Series Convertible measures 192.6 inches long on a 112.4-inch wheelbase.

Spec	Value
Vehicle
Body Type	Convertible
Powertrain	Gas
Price
MSRP	$89,700
MSRP with Destination	$90,695
Destination Charge	$995
Engine
Engine Type	3.0-liter turbocharged I6
Displacement	3 L
Horsepower	315 hp
Torque	330 lb-ft
Drivetrain
Drive Type	AWD
Transmission
Transmission	8-speed automatic
Fuel Economy
Tank Capacity	18.5 gal
Suspension
Front Suspension	Independent, double ball joint, gas shocks, coil springs
Rear Suspension	Independent, multi-link, gas shocks, coil springs
Dimensions & Weight
Length	192.6 in
Width	82.3 in
Wheelbase	112.4 in
Front Track	63 in
Rear Track	65.6 in
Cargo Volume	10.6 ft³
Interior
Headroom Front	40.3 in
Headroom Rear	36.5 in
Legroom Front	42.1 in
Legroom Rear	30.5 in
Shoulder Room Front	56.9 in
Shoulder Room Rear	49.6 in
Hip Room Front	60.3 in
Hip Room Rear	52.7 in

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Safety & Recalls

NCAP safety ratings

Tested, but no star ratings were published (2018 BMW 6 Series C AWD).

Recalls

No recalls on file with NHTSA for the 2018 BMW 6 SERIES.

11 owner complaints to NHTSA for the 2018 BMW 6 SERIES

Owner Complaints

11 owner complaints filed with NHTSA for the 2018 BMW 6 SERIES (1 mention a crash). See all on nhtsa.gov

Most-cited areas

Air Bags	2
Forward Collision Avoidance	2
Unknown Or Other	2
Electrical System	1
Engine	1
Lane Departure	1

A complaint can cite more than one area.

Most recent complaints

Jun 22, 2026 · Vehicle Speed Control

“The contact owns a 2018 BMW 640XI. The contact stated that while pulling up to a red traffic light, the brake pedal was depressed; however, the engine revved unexpectedly, and the vehicle unintendedly…”

Mar 19, 2026 · Unknown Or Other

“I hear a crackling or a popping sound coming from the windshield area as I’m driving. It is irregular and going over bumps seems to trigger it but yesterday as I was driving on a smooth highway with…”

Aug 26, 2024 · Air Bags

“My BMW's passenger side airbag malfunction light randomly came on and will not turn off. When I went to the dealer, BMW quoted apprx. $3000 to replace the seat sensor mat which they said probably got…”

Mar 31, 2024 · Air Bags

“Consistent passenger restraint / passenger airbag failure warning. Took vehicle to BMW dealership and was told that the passenger seat must have moisture damage, causing the issue. There have been no…”

Dec 7, 2023 · Unknown Or Other

“when opening the Panoramic Sunroof while driving, the curtain would not retract and sagged. It totally blocks the rear view and there is no way to fix it while driving. also if you have a car seat…”

Complaints are unverified reports submitted to NHTSA by owners. They cover the whole model year, not a specific trim, and a count alone doesn't show how common a problem is.

Source: US National Highway Traffic Safety Administration (nhtsa.gov), matched as 2018 BMW 6 SERIES. US-market vehicles only; data cached for up to 7 days.

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