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How to save gas money on your car

Here are some tips how to save money on gasoline without buying a Toyota Prius:

First some things to do about your car:

  • Keep your car tuned up. Cars in poor running condition use more gasoline. Spark plugs are cheap to replace, same applies to maintaining the right tire pressure. But do not overinflate either.
  • Make the car as efficient as possible. Remove roof racks when you do not use them anymore. I read somewhere that a car has 3% less drag (wind resistance) after it is washed, waxed and polished.
  • At freeway speeds, keep the windows closed to reduce drag.
  • Remove unnecessary weight from the car. If you can shed 150 lbs of dead weight (snow chains are a great example) that may correspond to 5% of the vehicle weight and roughly to 5% in fuel savings. Time to go on that diet again..

Now some tips that relate to the driving style:
  • If you have a manual transmission, always drive in the highest gear possible. You do not need to shift 1-2-3-4-5-6
    When you reach 45 mph in 3rd gear, you can actually go straight to 6th.
    Don't overdo this one though. I would try to keep the rpms at least at 2000 - but this depends highly on the individual engine, particularly on its torque curve.
    Automatic transmissions do that usually already. E.g. the stock Firebird Trans/Am (V8 engine, auto tranny) will shift very soon into highest (4th) gear to achieve its pretty good fuel efficiency. I say pretty good.. considering its 300+ horses..
  • In many cars fuel efficiency will go down by 10% if you have the air conditioner running. If you have a lower temperature setting, use it. Turn it on until the car gets cool, then turn it off and let the fan circulate the cool air. Certainly never run your AC with your windows open!
  • With cars that were built after 1990 you no longer need to warm your car up in the morning. Just drive the car gently in the first 5 minutes. The engine actually warms up better if it is driving instead of idling in your driveway. Some cars like the Mazda RX-8 automatically limit the RPMs until the engine is warmed up. (6000 rpm until engine is warm, afterwards you can hit 9600 rpm!)
  • Driving the speed limit aka "Driving insanely slow" will help a little as well. Maybe 10%.. read my separate article on this topic - Does Driving 55 mph help?
  • Try to accelerate slowly when leaving the stop light. It's not a competition with the driver in the lane next to you. The fastest person through the intersection just gets to spend more on gas. If you follow the tip of early shifting up, you won't be accelerating all that much anyway :-)
  • Try buying 87 octane gasoline instead of 91. Read the manual of your car. Some vehicles are marketed with the recommendation to use 91 octane gasoline, but the owner's manual actually says that 87 is fine. The Mazda RX-8 is such a car. Dealer will tell you 91, but it drives as fine with 87 rated gas and gets 10-15% more miles out of a tank. I personally only buy brand gas like Chevron, Union 76 and avoid the sometimes cheaper noname stations. Reason is, I found that the noname product is of inconsitent quality. Sometimes it is good, sometimes not. I even got pinging from a batch of Costco gas. Never again!
    I may save 10% on the purchase of noname gas, but it gets me 10% less miles on my tank.. so I stick to the brand gas.
  • Turn the engine off when you're stuck and expect not to move for a few minutes. When the engine is idling and not moving, you get 0 mpg.
  • Revving the engine needlessly wastes gas as well. Unless there is a mechanical defect with your vehicle, there is no need to rev before you turn your vehicle off. Consider fixing the mechanical defect before it turns into a more expensive one.


Tips to reduce driving
  • Obviously the best way to save gasoline is to drive less. Can you telecommute one day a week? Saves 20% on gas! If telecommuting is not an option, can you move your hours instead from 8 to 5 , what about working 10 to 7? You avoid traffic, save time and nerves and gasoline.
  • Can you share a ride with coworkers or even use public transportation? Public transportation is sometimes sponsored by the employer, ask for that. My previous employer gave us free train tickets to make our commute easier. The train did not go anywhere near my town though :-(
  • For short errands, think if you really need to use the car. If you include the time it takes to find a parking spot etc, it may be as fast to use the bicycle or even walk.


Some thoughts on the buying process:
  • Buy the gas where it is cheap and when it is cheap. E.g. I drive twice a week to a town where gasoline is consistently 20 cents cheaper than around my home. I try to fill up on those days.
  • Also fill up your car before any major holiday (not the last 2 days before, obviously) because some magic always drives prices up on those days.
  • If your car gets less than 25 mpg, consider buying a second car that is better on gas. I highly recommend Ford Festivas - designed by Mazda, assembled by Kia - they last forever. I bought one for $450 and have put 31000 miles on it so far. It saved me about $2000 in gas if I had driven those miles with 20 mpg sports car instead.
    When buying any such car, do some research what fuel economy to expect from this model. A manual transmission will usually do 5 mpg better than the auto tranny. My 5-speed manual transmission Festiva gets about 44 mpg mixed driving or 50 on pure highway driving (at moderate 65 mph).


It is a good idea to keep a log of the fuel consumption of your car. First, it makes you aware if the measures you take show effect. Second, by tracking the miles per gallon, you can see if anything changes with your car - that could be an early sign that there's something wrong. Underinflated tire or just the need for a tune-up.
To calculate mpg, fill the car up and reset the trip meter. If your car does not have a trip meter, write down the odo reading. Then drive the car for a week or so until the tank is nearly empty. Fill it up again. Look how many miles you drove since the last fillup and divide it by the number of gallons you had to put in.


Generated 0:01:00 on May 26, 2017