With each 5 mph increase how much does my gas mileage go down?

Question

With each 5 mph increase how much does my gas mileage go down?

Answer 1

It really depends on your vehicle, but as a rule of thumb, for each 5 mph increase in top gear, you lose 7% off your mpg.

Pushing the vehicle through the air becomes more difficult with increased speed, as the air needs to move out of the way faster and the increased speed means more air has to move.  

The best fuel economy you can achieve with an automatic is driving in the highest gear possible at the lowest speed.  With a manual transmission, you have to be able to cruise without forcing gasoline into the engine to keep it turning over.  If the engine is "shuddering", you're driving too slowly.  With a 5 speed, that's going to be about 40-45 mph, but you'll have to downshift to incnrease speed reasonably quickly, as the engine won't feed enough gasoline to speed up quickly.

Answer 2

you actually save the most gas driving at about 55 mph...

Answer 3

The more you increase RPM's the more gas is being burnt. You don't specify what you are driving does your car covert to less firing of cylinders when its at a cruise this will also be a factor.

Answer 4

It depends on the original speed and RPMs it's a sliding scale..it's not that simple

Answer 5

hard to say seeing as we dont know what kind of car you drive , wether its standard/ automatic , how many cylinders it has and how much horsepower.

they all play a role in this.

Answer 6

optimum fuel efficiency in overdrive is, truthfully, only 40-45.

Answer 7

well in my car i can do about 90 and get just under 30mpg on the highway and in the city its awful like 12mpg because i like to take off really fast lol but i end up getting 28mpg overall u should look at the bmw 323i