Question 1

What is MPG and how is it calculated?

Accepted Answer

MPG = Miles traveled ÷ Gallons used. Fill tank, reset odometer, drive normally, fill again, divide miles by gallons. EPA ratings use standardized dynamometer tests.

Question 2

Why is my real MPG different from EPA rating?

Accepted Answer

EPA tests are controlled conditions. Real-world factors: driving style, traffic, weather, terrain, AC use, cargo weight, and tire condition all affect actual MPG. City driving typically worse than rated.

Question 3

Why does the US use MPG while others use L/100km?

Accepted Answer

MPG (higher = better) is intuitive for comparing. L/100km (lower = better) better shows fuel savings - halving consumption halves L/100km but doesn't double MPG.

Question 4

How does speed affect fuel economy?

Accepted Answer

Most vehicles are most efficient at 45-65 mph. Above 65 mph, every 5 mph increase is like paying an extra $0.20-0.30 per gallon.

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