Compare the2025 BMW 4 Series ConvertibleVS 2023 Ford Mustang

For enhanced safety, the front and rear seat shoulder belts of the BMW 4 Series Convertible have pretensioners to tighten the seatbelts and eliminate dangerous slack in the event of a collision. The Ford Mustang doesn’t offer pretensioners for its rear seat belts.

The 4 Series Convertible’s pre-crash front seatbelts will tighten automatically in the event the vehicle detects an impending crash, improving protection against injury significantly. The Mustang doesn’t offer pre-crash pretensioners.

The 4 Series Convertible’s standard pretensioning seatbelts also sense rear collisions and remove slack from the seatbelts to help protect the occupants from whiplash and other injuries. The Mustang doesn’t offer a whiplash protection system.

The 4 Series Convertible has a standard PostCrash iBrake, which automatically applies the brakes in the event of a crash to help prevent secondary collisions and prevent further injuries. The Mustang doesn’t offer a post collision braking system: in the event of a collision that triggers the airbags, more collisions are possible without the protection of airbags that may have already deployed.

Over 200 people are killed each year when backed over by motor vehicles. The 4 Series Convertible offers an optional Active Park Distance Control that uses rear sensors to monitor for objects to the rear and automatically applies the brakes to prevent a collision. The Mustang doesn’t offer backup collision prevention brakes.

The 4 Series Convertible offers all-wheel drive to maximize traction under poor conditions, especially in ice and snow. The Mustang doesn’t offer all-wheel drive.

The 4 Series Convertible offers an optional Surround View to allow the driver to see objects all around the vehicle on a screen. The Mustang only offers a rear monitor and rear parking sensors that beep or flash a light. That doesn’t help with obstacles to the front or sides.

Both the 4 Series Convertible and the Mustang have standard driver and passenger frontal airbags, front side-impact airbags, driver and front passenger knee airbags, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, lane departure warning systems, blind spot warning systems, rearview cameras, rear cross-path warning and driver alert monitors.

The 4 Series Convertible comes with a full 4-year/50,000-mile basic warranty, which covers the entire car and includes 24-hour roadside assistance. The Mustang’s 3-year/36,000-mile basic warranty expires 1 year or 14,000 miles sooner.

The 4 Series Convertible’s corrosion warranty is 7 years longer than the Mustang’s (12 vs. 5 years).

BMW pays for scheduled maintenance on the 4 Series Convertible for 3 years and 36,000 miles. BMW will pay for oil changes, tire rotations, air filter replacements, cabin filter replacement, brake fluid replacement, inspections, and any other required maintenance. Ford doesn’t pay scheduled maintenance for the Mustang.

The battery on the 4 Series Convertible is in the trunk, which protects it from hot underhood temperatures that can degrade battery life. By keeping the 4 Series Convertible’s battery 20 to 30 degrees cooler, its life is increased by years. The Mustang’s battery is in the hot engine compartment.

A reliable vehicle saves its owner time, money and trouble. Nobody wants to be stranded or have to be without a vehicle while it’s being repaired. Consumer Reports rates the 4 Series Convertible’s reliability 21 points higher than the Mustang.

J.D. Power and Associates rated the 4 Series Convertible third among compact premium cars in their 2023 Initial Quality Study. The Mustang isn’t in the top three in its category.

J.D. Power and Associates’ 2023 Initial Quality Study of new car owners surveyed provide the statistics that show that BMW vehicles are better in initial quality than Ford vehicles. With 9 fewer problems per 100 vehicles, JD Power ranks BMW higher than Ford.

J.D. Power and Associates’ 2022 survey of the owners of three-year-old vehicles provides the long-term dependability statistics that show that BMW vehicles are more reliable than Ford vehicles. J.D. Power ranks BMW above average in long-term dependability. With 5 more problems per 100 vehicles in the first three years of ownership, Ford is rated lower.

From surveys of all its subscribers, Consumer Reports’ January 2024 Auto Issue reports that BMW vehicles are more reliable than Ford vehicles. Consumer Reports ranks BMW 13 places higher in reliability than Ford.

On the EPA test cycle the 4 Series Convertible gets better mileage than the Mustang Convertible:

			MPG
4 Series Convertible
RWD	Auto	2.0 turbo 4-cyl. Hybrid	27 city/35 hwy
		3.0 turbo 6-cyl. Hybrid	27 city/33 hwy
AWD	Auto	2.0 turbo 4-cyl. Hybrid	24 city/33 hwy
		3.0 turbo 6-cyl. Hybrid	25 city/32 hwy
Mustang Convertible
RWD	Manual	2.3 turbo 4-cyl. (310 HP)	20 city/27 hwy
		2.3 turbo 4-cyl. (330 HP)	19 city/25 hwy
		5.0 V8	15 city/24 hwy
	Auto	2.3 turbo 4-cyl. (310 HP)	20 city/28 hwy
		2.3 turbo 4-cyl. (330 HP)	19 city/26 hwy
		GT 5.0 V8	15 city/23 hwy

Regenerative brakes improve the 4 Series Convertible’s fuel efficiency by converting inertia back into energy instead of wasting it. The Mustang doesn’t offer a regenerative braking system.

In heavy traffic or at stoplights the 4 Series Convertible’s engine automatically turns off when the vehicle is stopped, saving fuel and reducing pollution. The engine is automatically restarted when the driver gets ready to move again. If the conditions warrant or the driver wishes, the system can be manually disabled at any time for the duration of a trip. The Mustang doesn’t offer an automatic engine start/stop system.

The 4 Series Convertible has a standard locking fuel door which locks and unlocks with the power locks. The fuel filler door is not lockable on the Mustang. A locking fuel door helps prevent fuel theft and vandalism, such as sugar in the tank.

The BMW 4 Series Convertible comes standard with an automatic transmission, for driver comfort, especially in the city. Automatic costs extra on the Mustang.

All wheel drive, available in the 4 Series Convertible, provides the best traction for acceleration in wet, dry, and icy conditions. In corners, all wheel drive allows both outside wheels to provide power, balancing the car. This allows for better handling. The Ford Mustang is not available with all wheel drive.

For better stopping power the 4 Series Convertible’s standard brake rotors are larger than those on the Mustang:

	4 Series Convertible	Mustang
Front Rotors	13.7 inches	12.6 inches
Rear Rotors	13 inches	12.6 inches

The 4 Series Convertible’s standard tires provide better handling because they have a lower 45 series profile (height to width ratio) that provides a stiffer sidewall than the Mustang’s standard 55 series tires.

For better ride, handling and brake cooling the 4 Series Convertible has standard 18-inch wheels. Smaller 17-inch wheels are standard on the Mustang.

Changing a flat tire near traffic can be dangerous and inconvenient. The run-flat tires standard on the 4 Series Convertible can be driven up to 50 miles without any air pressure, allowing you to drive to a service station for a repair. The Mustang doesn’t offer run-flat tires.

For a smoother ride and more stable handling, the 4 Series Convertible’s wheelbase is 5.1 inches longer than on the Mustang (112.2 inches vs. 107.1 inches).

The 4 Series Convertible’s front to rear weight distribution is more even (50.1% to 49.9%) than the Mustang’s (54.6% to 45.4%). This gives the 4 Series Convertible more stable handling and braking.

The 4 Series Convertible has 4.8 cubic feet more passenger volume than the Mustang Convertible (84 vs. 79.2).

The 4 Series Convertible’s standard rear seats fold to accommodate long and bulky cargo. The Mustang Convertible doesn’t offer folding rear seats.

With its convertible body style, valet key, locking rear seatbacks and remote trunk release lockout, the 4 Series offers cargo security. The Mustang’s non-lockable remote release defeats cargo security.

To make loading groceries and cargo easier when your hands are full, the 4 Series Convertible’s available trunk can be opened and closed just by waving your foot, leaving your hands completely free. The Mustang doesn’t offer a hands-free gesture to open its trunk, forcing you to put cargo down if your hands are full.

The 4 Series Convertible uses gas struts to support the hood for easier service access. The Mustang uses a prop rod to support its heavy hood. It takes two hands to open the hood and set the prop rod, the prop rod gets in the way during maintenance and service, and the prop rod could be knocked out, causing the heavy hood to fall on the person maintaining or servicing the car.

J.D. Power and Associates surveys of service recipients show that BMW service is better than Ford. J.D. Power ranks BMW 7th in service department satisfaction (above the industry average). With a 28% lower rating, Ford is ranked 22nd.

The 4 Series Convertible offers an optional heads-up display that projects speed, tachometer, warning and navigation instruction readouts in front of the driver’s line of sight, allowing drivers to view information without diverting their eyes from the road. The Mustang doesn’t offer a heads-up display.

The 4 Series Convertible’s power parking brake sets with one touch and releases with one touch or automatically. The Mustang has a lever-type parking brake that has to be strenuously raised to engage properly. It has to be lifted up more and a button depressed to release it.

The 4 Series Convertible’s front and rear power windows all open or close fully with one touch of the switches, making it more convenient at drive-up windows and toll booths, or when talking with someone outside the car. The Mustang’s rear power window switches have to be held the entire time to open or close them fully.

If the windows are left open on the 4 Series Convertible the driver can close them all at the outside door handle. On a hot day the driver can lower the windows from a distance using the keyless remote. The driver of the Mustang can only close the windows from inside the vehicle, with the ignition on.

In case of a sudden change of weather, the 4 Series Convertible offers an optional remote convertible top that can be raised from a distance to protect the interior of the vehicle from damage. On a hot day the 4 Series Convertible offers an optional remote opening feature, to lower the top from outside. The Mustang doesn’t offer a remote top, so the driver will have to run to the car, get in, turn the ignition on and raise the top to prevent the interior from being damaged.

To help drivers avoid possible obstacles, the 4 Series Convertible has standard cornering lights to illuminate around corners when the turn signals are activated. The Mustang doesn’t offer cornering lights. The 4 Series Convertible also offers optional adaptive headlights to illuminate around corners automatically by reading vehicle speed and steering wheel angle.

The 4 Series Convertible’s standard outside mirrors include heating elements to clear off the mirrors for better visibility. Ford only offers heated mirrors on the Mustang Premium/Mach 1.

When the 4 Series Convertible is put in reverse, the passenger rearview mirror tilts from its original position. This gives the driver a better view of the curb during parallel parking maneuvers. Shifting out of reverse puts the mirror into its original position. The Mustang’s mirror doesn’t automatically adjust for backing.

The 4 Series Convertible’s standard rear and side view mirrors have an automatic dimming feature. These mirrors can be set to automatically darken quickly when headlights shine on them, keeping following vehicles from blinding or distracting the driver. The Mustang has an automatic rear view mirror, but its side mirrors don’t dim.

The 4 Series Convertible has a standard dual zone air conditioning allows the driver and front passenger to choose two completely different temperatures so people with different temperature preferences won’t have to compromise. This makes both the driver and front passenger as comfortable as possible. Dual zone air conditioning costs extra on the Mustang.

For greater rear passenger comfort, the 4 Series Convertible has standard rear a/c vents to keep rear occupants more comfortable. The Mustang doesn’t offer rear vents.

To quickly and conveniently keep personal devices charged without cables tangling and wearing out, the BMW 4 Series has a standard wireless phone charging system (Qi) in the front center console. The Mustang doesn’t offer wireless personal charging.

The 4 Series Convertible’s optional Parking Assistant Plus can parallel park or back into a parking spot by itself, starting, stopping and changing direction automatically. The Mustang doesn’t offer an automated parking system.

The BMW 4 Series comes in coupe, convertible and four door hatchback bodystyles; the Ford Mustang isn’t available as a four door.

The BMW 4 Series outsold the Ford Mustang by 2172 units during 2023.