It's that time of year again when the weather is beautiful-we are putting the top down and hitting the road. Whether we are on our way to our favorite trail or just cruising and enjoying the weather, we cringe come fill-up time. We'd like to make it through one summer without getting gouged at the pump with artificially-increased prices. And at the end of summer when demand is lower, why not lower prices as well?
But we digress. The cycle of increasing gas prices for the summer travel season has been going on for as long as there has been OPEC, and we are helpless to stop it. However, there are ways we can stick it to the man with some simple and cheap (free!) ways to increase your Jeep's mileage and decrease your dependence on the oil company's teat.
Anytime that you decrease the mass of your rim and tire or decrease your rolling resistance, you will improve fuel mileage. Sure, you could go to a tire with a skinny contact area and lightweight rims, but the free way is to swap your factory kicks back on. Even if you've regeared, you'll get improved mileage this way. Bummer is that if you've regeared, your top-end speed might be limited, but around-town mileage will surely improve. Good for 2-3 mpg.
Leveling kits are all the rage-the problem is that they alter the aerodynamic profile of the vehicle. Basically, the less turbulence and air you have going under the vehicle, the better mileage you can get. So that leveling kit that raises the front end of your Jeep and makes it look "right" is also robbing you of precious fuel mileage. When we put the leveling kit on our Cherokee, we lost 1-2 miles per gallon.
Newer vehicles have tire pressure monitoring systems, but most of us stick with a gauge. Typically the more pressure you have in the tire, the less gas it takes to spin said tire. You are basically decreasing the tread width at the ground through pressure. The problem is, too much pressure and you will wear the tire out in the center. Enter chalk (or crayon). Draw a line across the tread and drive in a straight line for about 20 feet. Then check the line. The goal is to have pressure in the tire as high as possible without the center of the line wearing off before either end of the line. Good for 1-2 mpg (depending on how underinflated you run now).
If your tires are worn incorrectly (cupped or chunked), you are pouring more gas into turning them. Rotate your tires more frequently to get them to wear evenly. Rotate your spare into the equation and you'll get an extra 10,000 miles or so from your tires in addition to any mileage gains. Good for about 1 mpg.
For every 100 lbs you add to a vehicle it takes another 7 horsepower to drag it around. Get rid of unneeded weight. Think hard about adding heavy sound-deadener or a spray-on bedliner. Don't drag the Hi-Lift jack around and leave your spare tire at home if you are just cruising town. The added wind resistance of not having a top can actually drag your mileage down by 1-2 mpg whenwhen on the freeway.
From the Desk of Tech Editor Hazel
I solicited off-the-wall ideas for this story and here are some of the zany ideas that Hazel came up with. In theory they would all work, but we've yet to try any of them.
- Duct tape all body seams for less wind resistance.
- Create a large air damn under the front bumper that extends to within 4 inches of the ground to reduce the amount of air flow under the Jeep.
- Run thinner oil (0W20 in the engine) and switch to full synthetic oil. The reduction of parasitic loss should equal less wasted power.
- Remove roof rack, auxiliary lights, and passenger-side rear view mirror for less aerodynamic drag.