How do you know how many miles per gallon your vehicle should get?

Answer 1

Look on the sticker on the window before you buy, or ask the dealer. There will be 2 numbers given: average MPG for city driving under normal conditions, and Open Road under normal conditions.

However, many factors are involved with how many miles per gallon (MPG) you will average with your car. These include:

1. Type of vehicle
2. Age of vehicle
3. Whether new or used
4. Whether the car is maintained and serviced
5. Your driving habits, such as speed and braking
6. Type of road: city gets less; highway gets more
7. Environmental conditions, such as wind
8. Road conditions and traffic (more start-stop driving)
9. Whether you drive with your windows down or up; or if the car is a convertible

You can figure your gas usage by letting the tank get close to 1/8th or 1/4th tank full (use the same mark each time). Drive to the gas station and write down the numbers from the odometer, including the number that continually rolls (so your number will have a decimal, such as xxx.1. Fill your tank; write down how many gallons of gas you purchased. Repeat this next time you get close to your 'mark' you used before. Subtract the smaller odometer reading from the newest, larger reading. That is how far you traveled since your last fill-up. Divide this by total number gallons of gas purchased the first time. Then, fill up your tank again. Repeat, to get an average over a period of time.