The one trick that gets the best gas mileage

Drive slower and smoother. Keeping a steady, moderate speed (around 55 mph/90 km/h on open highways), anticipating traffic, and avoiding hard acceleration and hard braking deliver the biggest real-world fuel savings—often 10–30% better mileage than aggressive driving, according to U.S. Department of Energy and EPA guidance. Pair that with properly inflated tires, and no other single “hack” comes close.

Why speed and smoothness dominate fuel economy

Physics, not folklore, governs fuel burn. Aerodynamic drag rises with the square of speed, and the power needed to push air climbs roughly with the cube—so moving from 60 to 80 mph can slash efficiency by 20–30% depending on the vehicle. Meanwhile, aggressive throttle inputs and frequent braking waste energy as heat, especially in stop-and-go traffic where momentum is repeatedly lost. Federal testing shows aggressive driving can cut fuel economy by 15–30% on highways and 10–40% in cities, dwarfing the gains from smaller tweaks or add-ons.

How to apply the trick today

The following practical steps translate “slower and smoother” into daily driving without adding time or stress for most trips.

• Target a steady cruising speed near 55–60 mph on open roads when safe and legal; avoid sustained speeds above 70–75 mph.
• Accelerate progressively: think “half-pedal” to reach the desired speed, then hold it; avoid jackrabbit starts.
• Look far ahead and leave ample following distance to minimize braking; coast early toward red lights and downhill sections.
• Use cruise control on flat highways to iron out small speed variations; disable it on hilly or slippery roads.
• Time lights where possible and choose routes with fewer stops, even if they’re a mile longer.
• In manuals, upshift early without lugging the engine; in automatics, use Eco mode to encourage earlier upshifts.
• Avoid idling; if waiting more than 30–60 seconds, shut the engine off when safe and legal to do so.

These habits keep the engine in its efficient operating range, reduce aerodynamic and rolling losses, and preserve momentum—key levers for better mileage in any combustion or hybrid vehicle.

Other high-impact habits that stack with the main trick

Once your driving style is under control, these changes further boost economy—most cost nothing and pay off quickly.

• Set tire pressures to the door-jamb specification when cold; underinflation by 1 psi can lower mileage ~0.2% (up to ~3% total loss).
• Remove roof racks/boxes when not in use; external carriers can cut highway mpg by 10–25% depending on shape and speed.
• Lighten the load: every extra 100 lb can reduce economy by about 1% in smaller cars.
• Plan trips to bundle errands and avoid peak congestion; short, cold starts are disproportionately inefficient.
• Use climate control judiciously: at city speeds, windows-down is often fine; at highway speeds, windows-up with moderate A/C is usually more efficient than high-drag airflow.
• For hybrids, maximize gentle braking to capture regenerative energy instead of relying on friction brakes.

Together, these adjustments can add several percentage points to your baseline savings from smoother, slower driving.

Maintenance and setup that matter

A well-maintained car converts more of every gallon into motion. Focus on items that directly affect efficiency.

• Wheel alignment and correct tire balance to reduce rolling resistance and uneven wear.
• Fresh spark plugs and properly functioning oxygen sensors; a failing O2 sensor can significantly hurt mpg without obvious drivability issues.
• Use the manufacturer-specified oil grade; low-viscosity oils meeting the exact spec can improve mpg 1–2%.
• Air filter replacements help performance under high load; in modern fuel-injected cars they rarely change mpg dramatically unless severely clogged.
• Address any check-engine lights promptly—especially codes related to emissions and fuel trim.
• Use quality gasoline (Top Tier where available) to keep injectors and intake valves clean over time.

Staying on top of these basics prevents hidden efficiency losses that driving style alone can’t overcome.

Common myths—and what to skip

Some popular “tricks” either don’t work or compromise safety and legality. Here’s what to avoid.

• Premium fuel in a regular-fuel car: no mpg benefit and higher cost.
• Bolt-on magnets, vortex gadgets, and miracle additives: no credible, repeatable gains.
• Coasting in neutral or engine-off coasting: unsafe, often illegal; modern engines use near-zero fuel during in-gear deceleration above idle.
• Excessively overinflating tires to cut rolling resistance: can reduce grip and cause uneven wear—stick to the door-jamb spec.
• Long idling to “warm up”: wastes fuel; drive gently to warm the engine faster.
• Drafting close behind trucks: dangerous and illegal tailgating, despite theoretical drag reduction.

Focusing on proven techniques keeps you safe and yields consistent, measurable savings.

City vs. highway: tailoring the approach

The same principle—smooth and steady—applies everywhere, but the emphasis shifts with speed and traffic patterns.

• City driving: prioritize anticipation, gentle launches, early coasting to red lights, and route choices that reduce stops.
• Highway driving: choose the right lane, lock in 55–60 mph where appropriate, minimize roof drag, and avoid rapid passes.
• Hilly terrain: build a little speed before uphill grades and ease off on the climb; let gravity help on descents without excessive braking.

Adapting to conditions turns one core strategy into consistent gains across different environments.

How much you can realistically save

For a typical gasoline car rated at 30 mpg highway, cruising at 60 mph instead of 75 mph can raise real-world mileage to roughly 34–38 mpg, depending on aerodynamics and gearing. Layer in smooth driving, correct tire pressures, and trip planning, and many drivers see 10–25% better fuel economy without changing vehicles.

Summary

The single most effective “trick” for the best gas mileage is to slow down and drive smoothly—hold a steady speed around 55–60 mph on open roads and avoid hard acceleration and braking. It’s simple, safe, and validated by physics and federal data. Add proper tire pressure, light loads, smart route choices, and basic maintenance, and you’ll lock in the biggest, most reliable savings at the pump.