Fuel economy: What really matters.

Want to keep your motor fuel bills down? Tips abound, ranging from keeping the tow vehicle "tuned up" to adding swamp juice to the fuel tank. Driving a car is one thing, pushing a motorhome down the road--or pulling a big fiver--is another. Here are some things from the real world experiences of RVers to consider:

puuikibeach on flickr.com

Is it weight--or something else?  Thinking about changing RVs and concerned about the heavier weight of your prospective RV? Think again. One RVer, using the same pickup as a tow unit, did comparisons of his fuel economy towing his travel trailer (8,000 pounds) versus his enclosed cargo trailer that he uses for work (12,000 pounds). Results? Doing "round town" driving with stop and go traffic and a lot of startups, his heavier trailer hits him harder in the wallet. But put them both out on the highway and there's very little discernible difference in fuel consumption. It doesn't look like weight has much to do with it.

What about "front surface area"? Our personal experience and that of other RVers answers this question in a hurry. We bought our current travel trailer as a pre-owned unit. The other folks had the rig set to tow behind a 4x4 pickup, so when we got it, it was a bit too tall for our liking. After a couple of trips we "flipped the axles" back to the factory height and got trailer about six inches closer to the ground. Our fuel economy immediately improved.

Other RVers report similar experiences. One says by "flipping the axles" on his rig, and raising his rig about six inches, he watched his fuel economy drop from ten miles per gallon to about eight and a half. He also reported increased transmission temperatures with the bigger "to the wind" profile of the trailer--to the point he blames a transmission failure on the change over.

Wind resistance is a huge factor in fuel economy--it's like adding a ball and chain. If fuel economy matters to you, when rig shopping, look for the least amount of front profile.

Brett Jordan on flickr.com

And what about speed? Here's one you can test on your own. Try keeping your rig at 50 or 55 miles per hour over a couple of tank fulls. Then compare the fuel consumption at 60 or 65 miles per hour. We think you'll prove to yourself that driving at a lower speed can make for a dramatic improvement in fuel economy, and help keep engine and transmission temperatures at a "happier" spot. In real terms, if you do a 250 mile per day haul, the difference in "road time" is only 40 minutes between a 65 miles per hour and 55 miles per hour.