Whether you’re an owner/operator, or a truck fleet manager, fuel expenditures are probably always near the top of your mind. Fuel is a major expense, and it’s also the main one we have several ways to control. This helps explain why drivers and managers spend a lot of time and effort on optimizing their fuel usage.
To give an idea of how big an impact fuel strategies can have: Michael Roeth, the executive director of the North American Council for Freight Efficiency, said that, comparing the “worst driver” and the “best driver,” the difference in fuel economy could be up to 25%.
Let’s put that in some real-world terms. Let’s say there’s one driver who has not put much work into optimizing his fuel usage. He runs an average of 100,000 miles a year with an average of 6.2 MPG, using 16,129 gallons. With an average fuel cost of $2.566/gallon, that’s $41,290 in fuel costs per year.
Let’s say there’s another driver with the same routes and the same truck, except that he’s very focused on optimizing fuel costs. With the various changes he’s made to his driving style and truck, he gets 7.75 MPG, which means he only spends $33,032 on fuel: a 25% improvement.
And actually, the 25% estimate seems like it’s likely to be on the conservative side. We’ve read in some articles and forums lately about owner-operators improving their MPG by 50%! (Here’s the source for that claim.)
And because fuel is such a huge cost, reducing fuel cost results in a huge increase in take-home pay: even more than the MPG improvement. For many owner-operators, optimizing fuel economy is just like giving themselves a huge raise. (In the article linked in the above paragraph, the trucker in question claims to have quadrupled his net revenue by optimizing his fuel efficiency.)
This article will give a quick overview of some of the major ways to improve fuel efficiency. If you need more details on these subjects, there are plenty of online resources and articles with more in-depth information. (Or feel free to reach out to us at Rigbooks; we’re happy to help.)
Probably at the top of the list in terms of easiness and its effect on fuel efficiency is just slowing down.
Not very long ago, it was a common trucker belief that trucks got better mileage at faster speeds. (Click here for a National Geographic article that talks about this myth and how it was disproved.) Now we know better. Now we know that, on average, the following rule holds true:
For every single MPH increase in speed, there’s a corresponding 0.14 mpg penalty in fuel consumption.
Put in real-world terms, a truck that cuts its speed from 75 mph to 65 mph will get up to a 27% improvement in fuel consumption.
Sometimes drivers have motivations to get the job done more quickly. Maybe they want to get to another job they have scheduled; maybe they have something personal going on; maybe they’re just tired and want to get the job done. But as a driver, you should know that you are directly impacting your wallet every time you go faster than is necessary.
Cruise control is okay once you reach cruising speed and if you’re on a flat stretch of road. But when going up or down hills and when switching gears, you should have cruise control turned off, as it causes unnecessarily high revving when switching between gears.
If you’re a manager, it can be hard to monitor the driving habits of your drivers. One solution is to install speed limiters, also known as governors. These are not very popular, but they are an option. Maybe even the threat of installing a governor might be enough to straighten up your drivers!
Besides the obvious benefits to fuel costs, driving slower is just generally safer, and results in less accidents. And that’s another way you end up saving money with lower speeds.
Most truckers know about “progressive shifting,” which is recognized as the best way to switch gears. Progressive shifting is based on the philosophy of keeping your RPMs as low as possible as you switch through the gears. Instead of letting the RPMs rev high before switching, you switch as early as possible; this keeps the RPMs low as you enter the next gear. The lower the RPMs, the less your engine is working and the less fuel you’re burning. This results in a significant long-term savings in fuel costs.
Here’s a good video showing a driver doing progressive shifting. There are many resources and articles out there for how to get better at progressive shifting. Because every truck has different engine specifications and gear systems, we’d recommend doing some research on forums and with trusted associates to see what people say about the best driving techniques for your truck.
As an added benefit: progressive shifting is much easier on your engine and will result in less maintenance costs and repairs over the years.
In some modern trucks, you can activate progressive shifting from within your truck’s computer. This configuration prevents your truck from revving above a certain RPM, basically forcing you to do progressive shifting.
Truckers want to be comfortable when they sleep, and many leave the truck idling overnight to run the AC and other accessories.
For every hour of idling, an average truck burns between 1 and 1.5 gallon of gas. At current prices (about $2.50/gallon), that’s about $20 for 8 hours of sleep. If you’re driving 5 nights a week, that’s $100 per week. And if you’re driving 48 weeks of the year, that’s $4,800 in idling costs.
Now obviously there is value in staying comfortable, and maybe that expense is worth it to you. But if you want to cut idling costs, there are other cheaper ways to stay comfortable. A couple alternative ideas:
Tire pressure is a major factor in improving fuel efficiency. Just as you remember from riding a bike, a flat tire makes you go slower. Because there’s more tire contacting the road, it takes more energy to move the flat tire forward. This is why you should get in the habit of often checking tire pressure. Some drivers check them at every fuel stop.
Also, not all tires are made equal. Some tires have lower roll resistance, which means they are more capable of continuing to rotate on their own, without added energy. A lower rolling resistance means the tires will use less energy to travel a given distance. Here’s a Wikipedia article that talks about roll resistance and gives some tire brands ranked by “wastefulness.” If you put in a lot of miles and improving fuel efficiency is very important to you, buying better tires is probably a good investment.
“Super single” tires are becoming increasingly popular. They are extra-wide tires that take the place of two normal-sized tires in a big rig. Studies show that these tires get significantly better gas mileage. (Some people claim that they decrease safety, because when they blow out, they can cause more instability and damage than normal tires, but we haven’t seen a reliable source showing this is a serious concern. Anyone have any reliable info? Send it our way!)
As you probably know, aerodynamics is an important issue for trucks. The less of an obstacle your truck presents to the air, the less drag you’ll create and the less fuel you’ll burn.
And it’s even more important than you might instinctively guess. This is because wind resistance increases quadratically with speed, not linearly. This means that if you double your speed, your drag actually becomes 4 times what it was, not just double what it was. This helps explain why experienced truckers (and of course NASCAR drivers) do so much to combat the effects of drag.
There are a few accessories you can add to your truck to improve air flow. Here are just a few:
The space between the trailer load and the truck is called the air gap, and this could be a significant source of drag. You want the space to give enough room to turn the truck without hitting; this will depend on your specific truck specs. The smaller you can get the air gap, while leaving room for turning, the less drag you’ll have.
There are a lot of engine-specific ways to optimize fuel consumption. Three of the major ones are:
Lowering horsepower settings. You can actually lower your horsepower settings in some truck’s computer. This is similar to lowering your RPM capacity or speed, basically forcing you into burning less fuel. (This is somewhat controversial, with some people pointing out that in some cases higher horsepower, used correctly, will give you better mileage.)
Charge-air coolers. Also known as CACs or air-to-airs, these devices cool the air before it enters the engine, resulting in more efficient running. If there are leaks in the system, it won’t perform optimally. You can have your mechanic check the condition of your CACs.
Running the overhead. Also known as “doing the overhead,” this refers to adjusting the engine valves for optimal performance. This is usually something you do after your truck has been “broken in” a bit, maybe after the first 100,000 miles or so. After that, you might do it every 100,000 miles, or about once a year.
Improving fuel efficiency shouldn’t be thought of as a “one-and-done” kind of thing. It should be an ongoing process of continual improvement, one that you occasionally, a few times a year, give some thought to improving. The most successful drivers and owner-operators are constantly thinking of ways to drive more efficiently; they read up on forums for tips and learn about new technologies to help make that happen.
Part of getting real fuel use improvement is keeping accurate records. You should definitely have accurate and exact logs of your trips, your maintenance, and your fill-ups. The more accurate the log is, the more insight you will get into your fuel consumption, and the more accurately you’ll be able to pinpoint improvements and issues.
It may seem like a pain to keep very accurate records, but it is so important to optimizing fuel efficiency and is a small pain compared to the large potential savings you can gain. You can keep records in plain old notebooks, or you can use one of the many trucking software applications available today.
Hopefully this article has given you some basic insight into improving fuel efficiency for your rig or truck fleet. In future articles, we’ll discuss other, more specific fuel efficiency improvement techniques and strategies.
If you have any questions about this article or want to learn more about how our software, Rigbooks, can help you with improving your fuel efficiency, send us a message on our Contact Page.
My name is Jason Forrest, and I’m the creator of Rigbooks. Rigbooks is a cloud-based software that makes it easier for small and medium-sized trucking companies run their business while keeping organized. We’ve been around since 2010.
A little about me: I grew up in a trucking family and from an early age I learned about the day-to-day problems that truck owner/operators have to deal with. I was into computers and programming as a kid so over the years I helped write small computer programs that helped my parents run their company better. Eventually that led to the idea of putting all those tools together in one package. And Rigbooks was born.
Here's how to improve your Semi Truck MPG which can give you more profit in your owner operator business.
The average independent owner-operator works at a 5% profit margin—not including salary. What does that mean? And how can you estimate yours?
A breakdown of the most important factors to consider when buying a new truck, including the best truck for owner operators
Guide on how to start a trucking business as an owner operator, including getting paid, expected costs, and more.
How to stop neglecting preventative maintenance in your truck and save a ton of money in repair costs.