BMW 3 Series vs Cadillac CT4

The BMW 3 Series is the more efficient of the two: it reaches 36 mpg combined versus 27 mpg for the Cadillac CT4, a 9 mpg advantage and costs about $600 less per year to fuel.

Across 5 measured categories, the BMW 3 Series leads in 5. Figures are EPA test data, not manufacturer claims.

2015–2026

BMW 3 Series

Compact Cars · 105 configurations

36mpg combined (best)
All BMW 3 Series specs

2020–2026

Cadillac CT4

Compact Cars · 52 configurations

27mpg combined (best)
All Cadillac CT4 specs

Head-to-head specifications

MetricBMW 3 SeriesCadillac CT4
Best combined MPG36 mpg27 mpg
Best city MPG31 mpg23 mpg
Best highway MPG43 mpg34 mpg
Lowest annual fuel costEPA estimate at 15,000 miles per year$2,200$2,800
Lowest CO2 output158 g/mi327 g/mi
Engines offeredSIDI & PFI; Mild Hybrid, SIDI, SIDI; PHEV, SIDI; Mild HybridSIDI
TransmissionsAutomatic (S8), Manual 6-spdAutomatic (S8), Manual 6-spd, Automatic (S10)
DrivetrainsRear-Wheel Drive, All-Wheel DriveAll-Wheel Drive, Rear-Wheel Drive
Fuel typesPremium, Premium and Electricity, DieselPremium
EPA classCompact CarsCompact Cars
Years covered2015–20262020–2026
Configurations on record10552

Source: EPA fuel economy records via fueleconomy.gov. Best-case values across all recorded configurations for each model.

3 Series vs CT4: common questions

Which is better on gas, the BMW 3 Series or the Cadillac CT4?

The BMW 3 Series is the more efficient of the two: it reaches 36 mpg combined versus 27 mpg for the Cadillac CT4, a 9 mpg advantage and costs about $600 less per year to fuel.

Which costs less to run per year?

By EPA estimates at 15,000 miles a year, the BMW 3 Series runs about $2,200 a year in fuel at its most efficient configuration, versus about $2,800 for the Cadillac CT4 — a difference of roughly $600 per year.

What engines do the 3 Series and CT4 offer?

BMW 3 Series: SIDI & PFI; Mild Hybrid, SIDI, SIDI; PHEV, SIDI; Mild Hybrid. Cadillac CT4: SIDI.

Are they in the same vehicle class?

Yes — the EPA classifies both the BMW 3 Series and the Cadillac CT4 as Compact Cars, so they compete directly.

More 3 Series comparisons

Comparison id: bmw-3-series-vs-cadillac-ct4