Gas Mileage

[JustMeUC]

Gas Mileage Tips - Driving More Efficiently

Drive Sensibly

Aggressive driving (speeding, rapid acceleration and braking) wastes gas. It can lower your gas mileage by 33 percent at highway speeds and by 5 percent around town.

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One of those things I always wonder about:

I see it over and over again that hard braking hurts your gas mileage but WHY? I am sure it is not good for your BRAKES.. but can someone explain - how does rapid braking hurt gas mileage?

 

[GrayHare]

It's not the braking itself but an indication of wasted momentum, and thus gasoline.

 

[Zathras]

I am guessing it isn't the braking so much as what the hard braking means.
If someone is zipping along and comes to a screeching halt, they are keeping their foot on the gas pedal longer than someone who starts coasting further back, such that they slow down more gradually.

 

[padlin00]

What GaryHare says. Staring at my fuel monitor instead of the road has shown I get about 10% better mpg if I can coast to a stop, or as close as reasonable, and start up very slowly. I actually did it for a week to see if it helped, about 250 miles. Having to stop at all is the problem as well as speeds over 55. I also got a bit better mpg not using cruise.

I now drive like a normal male, way too much effort to drive so conservatively.

 

[ERhoosier]

Driven the exact same suburban/urban route to w#rk for many years. I've come to realize that (in pre-rush hour traffic) it takes me ~30min NO MATTER HOW AGGRESSIVELY I DRIVE! Believe me I've been late/stressed & tried to push it with jack rabbit starts/stops & weaving through traffic but I pull into garage within +/- 2min no matter what. Speed up to make one light & it sets ya up to miss the next. Interestingly some of my best times have been driving conservatively, which I'm sure is just 'luck of the stoplights'. Fact is you are going no faster or further than the bumper or stoplight in front of ya. Now I just drive easy 'cause I know the stress of fighting traffic for a few yards of urban asphalt means NOTHING in terms of time saved.

OTOH- mileage is a different story. Driving consistently aggressively in my mid-size sedan (4cyl) I ave ~22mpg (actual gas in tank, not car's computer) over several tankfuls. Driving a bit conservatively (keeping up with traffic but NO exotic hypermilling techniques) I consistently ave 27-28mpg.

GrayHare's absolutely right. Braking itself is not wasted energy but wasted momentum. Whatever speed you scrub with those brakes is energy (gas) you must spend gaining back momentum. (YMMV driving a hybrid)