Does driving slower save gas?


When I first started driving I drove slow bc I thought it would save gas, then I started driving faster when a friend told me you use the same amount of gas whether you drive slow or fast (as long as it’s the same distance), you just would be driving fast for a shorter amt of time and driving slow for a longer amt of time, but at the end you burner thru the same amount of gas. Is this true?

In: 5

Specifics will vary by vehicle, but in general, at higher speeds, cars generally start becoming less efficient. This can be especially noticeable at above 70-80mph in my experience.

Depends. Pretty much every engine has a peak performance zone – RPMs where fuel efficiency is at its maximum. Lower or higher than that and it will burn more fuel.

Now, the speed that results at that RPM is dependent on what gear you are in. So you might save gas by going faster or slower, depending on RPM, or _both_ assuming you switch gears.

Depends on the car, but sort of. There’s almost a bell curve. There’s a point where it’s best, and it falls off on either side.

The key to gas mileage is rpms. Doesn’t matter what gear you’re in, your car has a sweet spot for rpms that is the most fuel efficient

In general driving slower reduces the friction due to air resistance which means it requires less energy to maintain the speed and therefore save fuel. The slight issue with this is that engine fuel consumption is not linear. So reducing the speed does not save as much gas as you would expect if you just calculated the air resistance. In fact if you end up in the wrong gear and the engine is running too slow or too fast then it might require more fuel then driving faster. However this is just in certain special cases. So in general you do save gas by driving slower.