Boost Your 2021 BMW M3 Fuel Economy
You can lift your 2021 BMW M3's 16 city and 23 highway mpg by 3% to 33%. Correct tire pressure, smooth acceleration, moderate speeds, and regular maintenance deliver these gains. Keep auto start-stop on and use Efficient mode for daily drives.
The twin-turbo S58 engine pumps out 473 horsepower. Throttle control matters most. Hard launches and late braking drop mpg by 10% to 40% in traffic. Speed kills efficiency too. Cruise at 75 mph and you burn 10% to 20% more fuel than at 65 mph. Drag rises fast with speed. Wide performance tires lose 0.3% fuel per 1 psi under spec. Idling wastes fuel at 0 mpg. Roof racks cut another 3% to 5%. Fresh oil and filters ease engine work for 1% to 3% gains.
Here is a snapshot of key savings:
| Tip | Estimated Savings |
|---|---|
| Smooth acceleration and braking | 10% to 33% |
| Set tires to door sticker pressure | 0.3% per 1 psi corrected |
| Drive 65 mph instead of 75 mph | 10% to 20% |
| Remove roof rack and excess cargo | 3% to 5% drag, plus 1% per 50 lb |
| Fresh oil and air filter | 1% to 3% |
| Keep alignment in spec | 1% to 2% |
Action Steps to Start Today
- Check tire pressure weekly when cold. Match the driver door sticker. Recheck after temperature changes. Fix alignment if the car pulls or tires wear unevenly.
- Switch to Efficient engine mode and Comfort transmission for commutes. Shift early at 2,000 to 2,500 rpm. Use cruise control on flat highways.
- Cap speeds at 55 to 65 mph when safe. Small drops save double-digit fuel percentages.
- Skip idles over 30 seconds. Enable auto start-stop. In cold weather, drive gently to warm up instead of long idles.
- Drop weight. Empty the trunk, ditch unused racks, store track gear at home. Shed 50 to 100 lb for 1% to 2% gains.
- Follow maintenance. Swap oil and filter every 7,500 to 10,000 miles or yearly. Change air filter every 15,000 to 30,000 miles, sooner in dust. Check plugs at 30,000 miles. Tighten the gas cap.
- Pick low-rolling-resistance tires for street use. Skip ultra-sticky track compounds.
- Fuel smart. Use Top Tier 91+ octane. Open windows at low speeds. Run AC on highways at moderate settings.
- Plan routes. Combine trips to keep the engine warm. Dodge peak traffic.
Sidekick tracks your M3's fuel use, habits, and maintenance. It sends reminders to max your mpg.