The Gasoline Mileage Book:

               How To Save Gasoline When You Buy A Car, And Take
                Care Of A Car

Written by Dave Berry

Last summer I got 23 ordinary driver and one ordinary car to do an unusual demonstration. The idea was to show how good car maintenance and informed driving techniques can really save gasoline. The results were impressive. Everybody saved gas. On the average, our drivers went 25.5 percent farther on a gallon. And I think a lot of drivers could do that well. Ask yourself the questions in this book. See if you don't find some new ways to squeeze more miles from a gallon of gasoline.

Is my car sabotaged ?

Hard to say. But from the results of part one of my test, I think a lot of cars are. Each of the test drivers ran a 222-mile city and country course in a car that I had carefully sabotaged with mileage handicaps. The ignition timing was set back five degrees. The engine was idling a little too rich and too fast. I'd put on bias-poly tires instead of radials. The tires were five ponds under inflated, hardly enough to notice. The wheels were just a hair out of alignment. Finally, I had filled the crankcase with 30-weith motor oil instead of better-mileage 10W-40. With all these handicaps, the 23 drivers still average 13.6 mpg in this first part of the test. Since that's not unusually low for a car of this make and year, I figure a lot of cars must have handicaps just as bad as the ones I put into our test car.  |

three basic ways to become a mileage miser. Buy car carefully. Our tests showed the "mileage cost" of optional equipment. Take good care of your car. Proper engine tune, tire pressure, and wheel alignment, plus radial tires and multigrade motor oil boosted mileage 14.6 percent in my test. Drive right. By accelerating gently, anticipating stops, and watching speed, we gained another 8.9 percent.

What's good mileage maintenance worth ?
 

It paid off in a big way in part two of our test. A 14.6 percent mileage improvement. Between parts one and two we switched from bias-ply to steel-belted radial tires. And I inflated them to the proper pressure. Those two changes by themselves probably improved gas mileage about seven percent. Correcting ignition timing probably accounted for another five percent. fixing the idle speed, correcting the wheel alignment, and switching to all-season 10W-40 oil combined to push us up to the total of 14.6 percent.

Tune-ups are expensive. Are they worth it ?

In addition to the performance advantages of a tune-up, you might get a mileage payoff. Figure it this way. If you engine is badly out of tune, it could waste five percent of its gas. For an average driver, that would add up to 35 gallons a year. These days, the value of that much gasoline would pay back a big chunk of the tune-up cost.

Can driving tricks really save gas ?

In part three, I told our test drivers these four driving tricks. And they improved their mileage another 8.9 percent.
1. Accelerate gently. You don't have to carry to creep away from a stop. Just take it easy.
2. Anticipate stops. Take your foot off the gas and let the car coast up to the intersection. (Keep it in gear, though, for safety). 
3. don't go too fast or too slow. Most cars get their best mileage around 35 mph. In our test, we didn't get over 50 on the freeway.|
4. Get into high gear quickly. If you have an automatic, lift your foot off the accelerator to make it shift earlier.

Am I supposed to creep around at a snail's pace ?

Of course not. My test group averaged 33 minutes to cover the 22-mile course in the first two runs before I explained the above mileage trips to them. The last run with the mileage tips took only six minutes longer.

What's the "mileage price" of optional equipment ?
 

It's the gas to run it and carry its extra weight throughout the life of your car. to demonstrate how they can add up, we got two new intermediate-sized cars, same make and model, One was equipped to be a gas miser; 6-clylinder engine, gas-saver thermostatic fan, economy rear axle, stock shift. The other car, while not really a bit gas guzzler, had some fuel-eating options-like air conditioning, power steering, V-8 engine, automatic transmission. We drove the two cars for 1,083 miles each, including 260 miles of in-town driving. The final score: With options-163. mpg. Without option-23.0 mpg. Based on a price of 58 cents per gallon, the extra gasoline to drive the loaded car the way we did for 10,000 miles would cost $ 104. The exact mileage penalty caused by such optional equipment depends on the type of driving,  the make, model and condition of the car; the weather; and the other factors. This demonstration shows only a general effect. If can't be used to predict performance in other cases. The gasoline price in the example is the approximate national average price for unleaded as of April 12,1976, calculated from published industry data.
 

What's the best way to save gas ?

Don't drive unnecessarily. Carpool. use public transportation. For short trips, bicycle and feet get you there for nothing. Conserving energy is still important. And nothing chops the gas bill like leaving the car in the driveway.

How much difference will the size of my car make ?
 

The annual savings you gain with a good mileage small car might be something you want to consider when deciding how big a car to buy. 

Courtesy Shell  Oil