Let's visit the topic of vehicular fuel economy. It's not realistic to believe that the cost of a gallon of gas is going to markedly decrease, given the politics and economics of the world's available supply of petroleum. This feature won't cover alternative fuels, hybrids, water or compressed air cars; we'll hit common sense stuff you can do to stretch your mileage. Admittedly, some of the items are not in the "gee whiz" category, but every little bit helps, right?
Francesca Clark, in her excellent post, covered a number of tips; I'd like to explore a couple of those in depth and add several more that are (perhaps) off-beat or not generally considered when thinking about saving fuel in your daily drive.
But first, the gallery!
Don't idle your engine excessively -- a no-brainer; if you are stopped in heavy traffic, you are getting zero miles per gallon; if I am going to be stopped more than 60 seconds, I shut the engine off.
Cruise control -- if you've got it, use it on flat ground (if you drive a bunch in hilly country, the cruise will cause excess fuel use trying to maintain your selected speed); it prevents the engine from "hunting" to find the appropriate engine speed versus road speed; same goes for automatic overdrive, keeping the engine speed lower versus road speed.
Don't drive excessively fast; we know (intuitively) that high speed driving uses extra fuel; aerodynamic drag is a major cause of excess fuel use. About 50-60% of engine power, at highway speeds, is used to overcome drag; it increases, roughly, at the square of the vehicle speed
"Time" your traffic lights; on my long trips, I try to slow down enough such that I don't come to a complete stop at a light; the downside here is that you tend to irritate the folks behind you, who want to rush to the light to use their PDA's or engage in mindless chatter on a cellphone.
Trucks: several things. There has been much discussion about whether or not to leave your tailgate up or down -- even the Mythbusters
hit this one; leave it up
, according to a number of folks
. I know it seems counter-intuitive, but facts are facts (I'm guessing the folks who make tail gate nets are not too happy with Adam and Jamie); tonneau covers reduce drag
Roof racks are a great convenience for trips, but aerodynamically, they are a real drag
; at least get one of those babies that is streamlined, and remove it after your trip.
Fuel economy is significantly affected by the weight of the vehicle
(other things -- horsepower, for example -- being equal) so lets take a look at that. If you live in the northern climes and your vehicle is subject to snow and ice loading, or you tend to keep a bunch of junk in your car or truck, or you have a van that has extra back seats that are never used, clean them out. Gasoline is heavy (about 6 pounds per gallon
); if feasible, only fill your tank half full each time; if you have a 30 gallon tank, the last 15 gallons costs you about 90 pounds of dead weight, although you gradually burn it off.
- Another significant factor in reduced fuel economy is rolling friction. Examples of this causing fuel waste are: four wheel drive engaged when not required; poor wheel alignment, where the tires are not pointing straight ahead when under load; improper inflation; brakes dragging; worn or improperly lubricated driveline components.
- Engine and driveline friction decrease your fuel economy; using "energy conserving" oils, keeping the engine and driveline fluids clean, and warming your vehicle properly (especially in cold weather) will all stretch your fuel mileage.
OK -- there you have it; I've done my best to enumerate some (certainly not all) of the tips to help you keep your bucks in your pocket. It's up to you now.