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Chrysler, LLC

Get MPG-Wise

The specter of three-figure fill-ups may or may not last (at least we hope they don’t), but you can get some control of your fuel bills with only a little effort. The two areas where you can influence fuel consumption include situational control and operational control.

Situational Control

Combine Errands—Set a standard for the minimum number of errands required before you fire up the truck.

Avoid Short Hops—To get maximum fuel economy from any engine it must be fully warmed up. That takes five to ten miles on a cool day (longer on a cold winter day) and three to five miles on a warm day.

Pick A Route—Frequent idling combined with stops and starts eats a lot of fuel. If you have a choice of routes, pick one with the least number of stops. Even if it’s a few miles longer, you may end up using less fuel.

Operational Control

Accelerate Briskly—High gear is where your truck is most fuel efficient, and you want to get there ASAP. Accelerating briskly into high gear and the appropriate speed burns less fuel than a long, lazy acceleration. Once in high gear, use light throttle pressure to keep it in high.

Avoid Idling—Idling burns fuel with no useful result. An average fuel-injected car or truck uses about the same amount of fuel to start as it does for about 10-15 seconds of idling. Gauge the length of the wait and do one of the following: a) idle in neutral to lessen the engine load or, b) shut the engine off.

Maintenance—A dirty air filter is the number one maintenance-related fuel-eater. Using a higher viscosity engine oil (heavier weight) than necessary for your climate can also cost fuel efficiency.

Minimize Warm-Ups—Except when winter safety demands some extra time to clear the windows, just start and drive away. The engine warms up more quickly and the fuel used is being put to a useful purpose. If you live in a cold climate, a block heater on a timer set to come on a couple of hours before you need it will help the vehicle to warm up faster.

Momentum Is Gold—When you’ve used fuel to gain speed, save that momentum like it was your last dollar by reading the traffic and trying to stay in motion. Accelerating from a slow roll uses considerably less fuel than from a dead stop—plus you avoid idle time.

Slow Down—The faster you go the more fuel it takes to push your truck through the air. The effect begins to take a serious bite above 50 mph for most vehicles. The less aerodynamic the vehicle the more speed hurts fuel economy. Here are some numbers personally tested on calibrated equipment: ’00 Honda Accord V6: 55 mph=30 mpg, 70 mph=29.4 mpg; ’05 Ford F-150: 55 mp=17.5 mpg, 70 mph=15.6 mpg. The aerodynamic car only dropped 0.6 mpg, the truck a whopping 1.9 mpg.

How To Check MPG

Divide the miles driven by the gallons used and get your miles per gallon:

miles driven/gallons used=mpg

The two most common errors are an inaccurate odometer and an inconsistently filled fuel tank. The odometer can be checked against highway mile markers or with a GPS. Say the odo shows 1.1 miles over a measured mile. Divide the actual miles by the indicated miles to get a correction factor (1/1.1=0.9). Multiply the correction factor by the indicated miles driven gets you the actual miles (e.g. 250 miles x .9 = 225 miles actually driven). Fillup level errors can be minimized by making sure your vehicle is level when adding fuel and always using the same notch on the auto shutoff nozzle. The most accurate results come from always using the same pump.

Tailgate Up—Everyone from Consumer Reports to the SAE has proven that the mpg is better on pickups with the tailgate up. Bed covers are proven to help a bit, even if they only cover the rear three feet of the bed.

Travel Light—Weight costs fuel economy—more so with low-powered vehicles than with higher powered ones, and more during in-town driving than on the highway.

Tire Inflation—Under inflated tires will cost you fuel economy. Check pressure frequently. With OE-sized tires, use the door frame tire placard as your guide. You can gain a tad of efficiency at the cost of ride quality by using the maximum rated pressure listed on the sidewall.

Sources

K&N Engineering

ScanGauge

Use The Cruise—Using cruise control in level areas where any steady speed is appropriate saves fuel. In hilly terrain, kick the cruise off and use downgrades to build “free” momentum for the next hill, and use as little throttle as possible to crest it at a good speed.

Windows And A/C—Using A/C in town costs you more mpg than having the windows down. At freeway speeds, the reverse is generally true. With trucks, many are as aerodynamic as a brick. Windows down at speed are less a factor than with a more sleek car.

—Jim Allen