Compare the2025 BMW 3 Series SedanVS 2025 Cadillac CT4

The 3 Series Sedan’s pre-crash front seatbelts will tighten automatically in the event the vehicle detects an impending crash, improving protection against injury significantly. The CT4 doesn’t offer pre-crash pretensioners.

The 3 Series Sedan 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 CT4 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.

The 3 Series Sedan’s driver alert monitor detects an inattentive driver then sounds a warning and suggests a break. According to the NHTSA, drivers who fall asleep cause about 100,000 crashes and 1500 deaths a year. The CT4 doesn’t offer a driver alert monitor.

Both the 3 Series Sedan and the CT4 have standard driver and passenger frontal airbags, front side-impact airbags, driver and front passenger knee airbags, side-impact head airbags, front seatbelt pretensioners, plastic fuel tanks, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, rearview cameras, available all wheel drive, lane departure warning systems, blind spot warning systems, around view monitors and rear cross-path warning.

The 3 Series Sedan’s corrosion warranty is 6 years and unlimited miles longer than the CT4’s (12/unlimited vs. 6/100,000).

BMW pays for scheduled maintenance on the 3 Series Sedan 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. Cadillac only pays for the first scheduled maintenance visit on the CT4.

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 3 Series Sedan’s reliability 14 points higher than the CT4.

J.D. Power and Associates’ 2024 Initial Quality Study of new car owners surveyed provide the statistics that show that BMW vehicles are better in initial quality than Cadillac vehicles. With 8 fewer problems per 100 vehicles, JD Power ranks BMW higher than Cadillac.

J.D. Power and Associates’ 2024 survey of the owners of three-year-old vehicles provides the long-term dependability statistics that show that BMW vehicles are more reliable than Cadillac With 6 fewer problems per 100 vehicles in the first three years of ownership, J.D. Power ranks BMW higher than Cadillac.

From surveys of all its subscribers, Consumer Reports’ January 2024 Auto Issue reports that BMW vehicles are more reliable than Cadillac vehicles. Consumer Reports ranks BMW 7 places higher in reliability than Cadillac.

The 330i’s standard 2.0 turbo 4-cylinder hybrid produces 18 more horsepower (255 vs. 237) and 37 lbs.-ft. more torque (295 vs. 258) than the CT4’s standard 2.0 turbo 4-cylinder. The M340i’s standard 3.0 turbo 6-cylinder hybrid produces 76 more horsepower (386 vs. 310) and 48 lbs.-ft. more torque (398 vs. 350) than the CT4’s optional 2.7 turbo 4-cylinder.

As tested in Consumer Reports the 330i 2.0 turbo 4-cylinder is faster than the Cadillac CT4 2.0 turbo 4-cylinder:

On the EPA test cycle the 3 Series Sedan gets better mileage than the CT4:

Regenerative brakes improve the 3 Series Sedan’s fuel efficiency by converting inertia back into energy instead of wasting it. The CT4 doesn’t offer a regenerative braking system.

To lower fuel costs and make buying fuel easier, the BMW 3 Series Sedan uses regular unleaded gasoline (premium recommended for maximum performance). The CT4 requires premium, which can cost on average about 84.9 cents more per gallon.

The 3 Series Sedan has a standard locking fuel door which locks and unlocks with the power locks. The fuel filler door is not lockable on the CT4. A locking fuel door helps prevent fuel theft and vandalism, such as sugar in the tank.

In its Green Vehicle Guide, the U.S. Environmental Protection Agency (EPA) rates the BMW 3 Series Sedan higher (6 to 7 out of 10) than the Cadillac CT4 (5 to 6). This means the 3 Series Sedan produces up to 8 pounds less smog-producing pollutants than the CT4 every 15,000 miles.

The 3 Series Sedan’s launch control uses engine electronics to hold engine RPM’s precisely in order to provide the most stable and rapid acceleration possible, using all of the available traction. The CT4 doesn’t offer launch control.

For better stopping power the 3 Series Sedan’s brake rotors are larger than those on the CT4:

The 3 Series Sedan stops much shorter than the CT4:

For better ride, handling and brake cooling the 330i has standard 18-inch wheels. Smaller 17-inch wheels are standard on the CT4 Luxury.

The 3 Series Sedan offers an optional space-saver spare tire so you can replace a flat tire and drive to have the flat repaired or replaced. A spare tire isn’t available on the CT4; it requires you to depend on its run-flat tires, which limits mileage and speed before they are repaired. If a run-flat is damaged beyond repair by a road hazard your vehicle will have to be towed. Some tire options on the CT4 don’t have a run-flat feature, either.

The 3 Series Sedan offers an optional driver-adjustable suspension system. It allows the driver to choose between an extra-supple ride, reducing fatigue on long trips, or a sport setting, which allows maximum control for tricky roads. The CT4’s suspension doesn’t offer adjustable shock absorbers.

For a smoother ride and more stable handling, the 3 Series Sedan’s wheelbase is 2.9 inches longer than on the CT4 (112.2 inches vs. 109.3 inches).

For better handling and stability, the track (width between the wheels) on the 3 Series Sedan is 1.9 inches wider in the front than on the CT4.

The 330i handles at .99 G’s, while the CT4 Premium Luxury pulls only .85 G’s of cornering force in a Car and Driver skidpad test.

The M340i executes Motor Trend’s “Figure Eight” maneuver 1.5 seconds quicker than the CT4 Premium Luxury AWD (25 seconds @ .77 average G’s vs. 26.5 seconds @ .67 average G’s).

The 3 Series Sedan has .4 inches more front headroom, .8 inches more front shoulder room, 1.1 inches more rear headroom, 1.8 inches more rear legroom and .7 inches more rear shoulder room than the CT4.

The 3 Series Sedan has a much larger trunk than the CT4 (16.9 vs. 10.7 cubic feet).

A low lift-over trunk design makes loading and unloading the 3 Series Sedan easier. The 3 Series Sedan’s trunk lift-over height is 26.7 inches, while the CT4’s liftover is 30 inches.

Pulling a handle automatically lowers the 3 Series Sedan’s rear seats, to make changing between passengers and cargo easier. The CT4 doesn’t offer automatic folding seats.

With its sedan body style, valet key, locking rear seatbacks and remote trunk release lockout, the 3 Series offers cargo security. The CT4’s non-lockable folding seat defeats cargo security.

To make loading and unloading groceries and cargo easier, especially for short adults, the 3 Series Sedan offers an optional power trunk, which opens and closes automatically by pressing a button, or optionally by just kicking your foot under the back bumper, completely leaving your hands free. The CT4 doesn’t offer a power trunk.

The 3 Series Sedan uses gas struts to support the hood for easier service access. The CT4 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.

The 3 Series Sedan’s front and rear power windows all open or close with one touch of the switches, making it more convenient at drive-up windows and toll booths, or when talking with someone outside of the car. The CT4’s rear power window switches have to be held the entire time to close them fully.

If the windows are left open on the 3 Series Sedan 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 CT4 can only close the windows from inside the vehicle, with the ignition on.

The 3 Series Sedan’s rain-sensitive wipers adjust their speed and turn on and off automatically based on the amount of rainfall on the windshield. This allows the driver to concentrate on driving without constantly adjusting the wipers. The CT4’s standard manually variable intermittent wipers have to be constantly adjusted.

The CT4 Premium Luxury/Sport’s optional cornering lamps activate a lamp on the front corner when the turn signal is activated. The 3 Series Sedan’s optional adaptive cornering lights turn the actual headlight unit up to several degrees, depending on steering wheel angle and vehicle speed. This lights a significant distance into corners at any speed.

Both the BMW 3 Series Sedan and Cadillac CT4 offer exterior mirrors that can be folded to provide convenience. The 3 Series Sedan features standard power folding mirrors, which allow for easy, one-touch folding or unfolding at the driver’s discretion. This provides added convenience when maneuvering or parking, as well as when walking past the parked vehicle. In comparison, the CT4’s foldable mirrors are manual, requiring the driver to get out and physically fold them once parked and unfold them before getting in.

The 3 Series Sedan has standard heated front seats. Heated front seats cost extra on the CT4. The 3 Series Sedan also offers optional heated rear seats to keep those passengers extremely comfortable in the winter. Heated rear seats aren’t available in the CT4.

The BMW 3 Series Sedan has a standard Homelink wireless remote control system for garage door operation and device management, conveniently located on the rear view mirror. Homelink® eliminates the need for separate garage door openers and associated risks of losing, breaking, or having dead batteries. Homelink® is only available on the CT4 Premium Luxury/Sport.

The 3 Series Sedan’s optional Parking Assistant Plus can parallel park or back into a parking spot by itself, starting, stopping and changing direction automatically. The CT4 doesn’t offer an automated parking system.

Consumer Reports® recommends the BMW 3 Series Sedan, based on reliability, safety and performance. The Cadillac CT4 isn't recommended.

J.D. Power and Associates rated the 3 Series Sedan third among compact premium cars in owner reported satisfaction. This includes how well the vehicle performs and satisfies its owner’s expectations. The CT4 isn’t in the top three.

The BMW 3 Series outsold the Cadillac CT4 by almost four to one during 2023.