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5 Facts About Aerodynamics on Tractor Trailers

Learn how aerodynamic kits save fleets money on fuel.

Episode 122: Fleets are looking for ways to save money and fuel is one of the most expensive line items on a fleet’s list of expenses. One option is to add aerodynamics to a truck and trailer to reduce fuel costs, but how much money do aerodynamics save fleets? 

In this episode, we had David Black, the VP of Fleet Sales at Flow Below to join us and answer that question and help us better understand the other benefits of aerodynamics for fleets. 

Flow Below Logo, the experts on aerodynamics for fleets.

To learn more, go to FlowBelow.com.

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Complete Transcript of Episode:

Jamie Irvine:

You’re listening to The Heavy-Duty Parts Report. I’m your host, Jamie Irvine. And this is the show where you get expert advice about heavy-duty parts that keep trucks and trailers on the road longer while lowering cost-per-mile. Did you know that every Friday we go live at 10:00 AM MTN, 12 PM EST. You can follow us on YouTube, Facebook, or LinkedIn to watch our live broadcasts, but you can also head over to heavydutypartsreport.com to check out the replays of our live presentations.

Today on the podcast I’d like to share with you one of the live interviews that we’ve done recently, because I thought that it was something that would be of interest to you. I hope you enjoy this replay of a live interview we did not that long ago. When we think about transportation fleets, we think a lot about the maintenance and repair side of it. We talk on the podcast and on this live stream about the methods in which fleets can reduce their costs.

Today, we’re going to talk about aerodynamics. I’m excited to talk about that because I want to learn just how much money fleets can actually save by buying these parts that increase the aerodynamics of the vehicle, improve the aerodynamics of the vehicle. And in order for us to have that complete conversation, I wanted to have an expert in this on the show.

So I invited David Black who’s the VP of fleet sales at Flow Below to come on the show. He’s waiting backstage. Let’s get him out here. David, welcome to The Heavy-Duty Parts Report. So happy to have you here.

David Black:

Thank you for having me, Jamie. It’s pleasure to be here.

Jamie Irvine:

So David, I would like to kind of get the conversation started with really focusing first of all, on what the costs currently are. So when we talk about a fleet, when I asked them, what are the top three things you’re spending money, fuel is always right at the top of that list. So how much on average do you fleet spend on fuel on a single truck per year?

David Black:

It depends on a number of factors, the price per gallon, the miles driven in a year and the fuel efficiency of the vehicles. You know the retail rate on diesel fuels been on a steady rise this year. It started about 2.68 or so a gallon in January came up to about $3.38 cents in September and the numbers continue to climb. So additionally, you’ve got geographic factors of buying fuel in the west.

Western part of the United States was more expensive than in the central Atlantic states, for example, but generally the closer to the pipeline you are the lower the cost of the fuel. And then you’ve got larger fleets that have fuel incentives. They pay less than the average retail rate for diesel fuel or they contractually get prices locked in for a longer period of time. Then the miles driven can be all over the board.

Many of my fleets that I’ve talked to run miles of about 120,000 miles a year, some down in the, in the fifties and sixties, but we usually use an average of about a hundred thousand miles a year, and then the fuel efficiency of the vehicles, that can change as well. It’s driven by a number of factors, the routes they run, including topographical variations.

That’s why some of the new products like predictive cruise are so popular, you know, taking all that topography into account with the movement of the truck down the road. And then you’ve got last-mile versus regional haul versus long haul.

So when you put it all together and add the specs of the truck, you know, what kind of engine do they have, what kind of tires, axle and gear ratios, transmissions, what kind of aero devices they’re running and even the payload, a typical class eight truck, let’s say with the average that I mentioned before of a hundred thousand miles a year could be running anywhere from six-mile per gallon to up to nine miles per gallon.

If we assume seven, somewhere in the middle, and that that’s a pretty good average for the fleets that I speak with on a regular basis, and we use a fuel price of about $3 per gallon. The fuel expense would be about $43,000 a year. If you average that out, you could assume between $3000 to $6,000 a month, depending upon those factors that I mentioned previously,

Jamie Irvine:

This is exactly why I wanted you on the show because you’ve got the expertise. I’m asking what I think is a pretty simple question and you’re showing just how complex this issue actually is.

David Black:

You know, fuel is by far one of the largest variable expenses and operating a truck. It’s second only to driver wages and benefits. Now at Flow Below, we utilize an ROI calculator to help show the fleets, the savings opportunities, given their fleet-specific variables. So when I go in to visit a fleet, I will ask a lot of particular questions about their operation.

And once I know the fleet’s annual mileage per truck, the price they’re paying for diesel fuel, their trade cycles and the specific products that they’re going to install on their vehicle, we can calculate their approximate annual savings and get to the breakeven point for the ROI.

Jamie Irvine:

You talk about that breakeven point, but beyond that, like what kind of real-world savings have you seen customers of yours achieve once they factored in their variables?

David Black:

Once again, driven by the variables. But I would say if you to look at an average, probably about a $1000.00 a year per truck, if they are using our full Flow Below Aero kit, and then if they add our wheel covers to the trailer position, they’re going to increase that number probably by about $300 to $400.

Jamie Irvine:

So, it could get as high as maybe $1300 to $1,500 a year in real savings per truck?

David Black:

At $3 a gallon. And there are a lot of people out there paying more than that now.

Jamie Irvine:

So, let me ask you something, if the price of fuel goes up higher, the savings goes up more?

David Black:


Jamie Irvine:

Right, right. Because the cost per gallon is increasing. So Brian, a supporter of the show, he says, “keeping your fleet in alignment with good PM practices can save you a ton of money on fuel costs”. And of course, adding aerodynamics is what we’re talking about above and beyond that preventative maintenance program. Now we’re getting the maximum savings that we can achieve with a commercial truck. Thanks, Brian, for commenting, I appreciate that.

We’re going to take a quick break. We’ll be right back.

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So David, let’s keep talking about, you brought up all the variables that goes into this. This is not a straightforward situation because every fleet, depending on vocation, like you said, depending on what kind of price they can get their fuel at, this all has an impact on what fleets can achieve.

So which vocations are best suited for aerodynamics versus other vocations that perhaps wouldn’t be achieving as much savings. So I’d like to know kind of what fleets we’re talking about.

David Black:

Well, certainly, you know, operators running long haul routes, any aerodynamic technology is going to make a difference. Generally speaking, the more miles a truck runs in a year, the more impact that aerodynamics will have. Fleets that run sleeper teams are obviously a natural fit. They’re great candidates for investing heavily in aerodynamics, but really any truck or fleet that’s looking to improve their MPG.

Now, if you get into, you mentioned vocational trucks, if someone is a purely local, never leave town pick up and delivery vehicle and they don’t get up over maybe 30 miles an hour in a given day, they’re probably not a candidate for aerodynamic fuel improvement.

Jamie Irvine:

So like a garbage, compact or something, that’s kind of just in an urban area going low mileage as well as slow speeds, physics just isn’t working in their favor on this.

David Black:

Typically, you know, the studies have shown if you’re moving more than 40 to 45 miles an hour, aerodynamic technology has a positive impact. So basically from zero to 40 to 45 miles an hour, the truck is overcoming rolling resistance. So as a result, factors such as rubber compounds in the tires, torque gear ratios, those things have the greatest impact.

But once you get to that 40, 45 mile an hour and over it’s all about aerodynamics. So we’re beginning to see a lot of retail, grocery haulers, private fleets, LTL carriers, starting to take more care in choosing their aerodynamic packages. And as I said, many private fleets are doing the same thing now as well.

Jamie Irvine:

So you mentioned a couple of different products. Maybe you could talk to me about the investment required to put like a full package. What does that mean? What are we talking about in real-world costs? And then how quickly do they get their money back in fuel savings?

David Black:

Well, typically the Flow Below products are available at every major OEM in North America. So the pricing has to come through the dealer by way of the OEM if you’re going to put it on a new truck.

Jamie Irvine:

What about aftermarket options?

David Black:

If you’re looking in the aftermarket for the full Aero kit, you know I would go and assume about a $1,500 bogey and you’re looking at realizing that full ROI breakeven point probably in about 14 to 15 months.

Jamie Irvine:

Okay. And then it’s money after that, money in the bank. And are you using a distribution channel on the aftermarket side? Like is it repair shops that have to install it and you sell through, or is there parts stores that people can buy these products at?

David Black:

Every OEM truck manufacturer offers our products today and they all have access through their own parts networks to receive the Flow Below products. In addition to that, our wheel covers are standard at DTNA and also at Navistar.

Additionally, we’ve worked with some of the OEMs to develop more fleet-specific fairing products that match their specific chassis to maximize the return. And those products are only available through the OEM. And I can’t even give you a price on that, but I can tell you that regardless of which product the fleet’s running, the ROI is there. And the OEMs have all done rigorous testing to validate the product and its installation utilization on their platforms.

Jamie Irvine:

Let me ask you this, David, if there is a proactive salesperson who works for an aftermarket parts company, maybe one of the HDA Truck Pride members, and he or she is out there really trying to generate some new business for you is there’s an opportunity for the aftermarket to purchase these products?

David Black:

I think that they need to give us a call or get in contact with us at www.flowbelow.com.

Jamie Irvine:

All right, well we’ll make sure those links are in the show notes. So when we talk about these products, we’re talking about the truck and the trailer for wheel covers, and then we’re talking about bolt-on products for the trailer. Is there any other bolt-on products for the truck?

David Black:

Our Flow Below Aero kit includes the drive wheel fairings, one that goes between the wheels and one that comes off the rear. Basically, we’re trying to divert the flow of air out from the side of the tractor to be picked up by, in most cases, a trailer skirt running along the length of the trailer. And then if you have our wheel covers on the trailer position, it goes straight off the back of the rig.

Jamie Irvine:

We’re going to take a quick break. We’ll be right back.

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So once these products are installed, is there any maintenance issues or any repair issues that come up because of the products like I’m just thinking how much a truck and trailer can travel and in one or two days, they can go from the deserts through to the Rocky mountains. Any issues that come up with this, that a fleet needs to know about?

David Black:

You know, any component that you have on a truck or a trailer, there’s certainly the possibility that maintenance will be required or that damage can occur. You know, accidents cause damage. Fleets have aerodynamic hoods on their vehicles and they don’t typically anticipate having to do anything with the hood when they purchase the truck.

But ultimately if you have an accident or hit a deer, for example, you’re going to be replacing a hood and a number of other things as well. But our Flow Below kit is a modular system. Meaning if you damage a piece of the system, only that damaged piece would need to be replaced. So you don’t have to purchase an entire new kit just to replace that one component.

Now there are active aerodynamic products out there that just run all the time and Flow Below would be one of those, you don’t typically have to deploy anything. There’s no real driver interaction involved. You put the product on the truck or the trailer, and it works. The aerodynamic mirrors would be an example, aerodynamic, hoods, fenders, bumpers, and so forth. And you install it, you leave it alone.

That works, but active products like the old-style trailer tails or some of the gap devices that are out there may be more vulnerable to damage and require more driver interaction. So exactly which components are right for your fleet and your application is a conversation that we need to have.

Jamie Irvine:

Okay, that sounds good. That sounds really good. So we talk about the money, but like what’s the other impact of adopting these types of products on a fleet? Like I know there’s like the exact ROI on like fuel savings, but I’m always kind of interested in the impact it has on the business. Is there any other kind of like things that go along beside that, that we’re not thinking about that would be a benefit to the fleet?

Does it improve the driver experience or maybe just share some of the feedback that you’ve gotten from fleets about how they feel about these products once they’ve had them installed?

David Black:

Absolutely. Well you know, certainly there are other fleet benefits for a variety of reasons. One is sustainability. Everybody’s all about improving sustainability of everything associated with the business and operations and the planet itself. And one of the things that we want to do as a, as a mission is to save 500 million gallons of fuel over the next 10 years, it’s a big goal and we have to sell a lot of product to do that.

But the customers that are utilizing our product and having tremendous success with it are going to be the ones to help us get there. And as the word spreads from them, that’s just going to increase the take rates and broaden the scope of, to the degree you see us on the road.

Now fleets look at sustainability because in some cases they have to report that to some of their customers, be it shippers, receivers, maybe even stockholders, or the general public. And then you also have the reduction in carbon emissions. If you’re burning less fuel, certainly you’re emitting fewer particles into the atmosphere and we in our ROI calculator factors those things in, and we can report that to the fleet as well. But beyond that, you have image issues, the general public and the shippers, they see that you’re trying to do your part, that you’re trying to improve the efficiency of your fleet.

And then there are other benefits that we don’t necessarily tout on a regular basis. For instance, you mentioned the garbage refuse hauler earlier in the show that would not be a candidate in my mind to get our aerodynamic wheel covers.

However, we have some fleets that have installed our aerodynamic wheel covers in order to keep foreign materials out of the wheel cavity. It’s not the reason we made the product, it’s just a reason that they found that they could positively utilize product. Another benefit is that the wheel covers help reduce the turbulence that’s generated by the spinning wheel itself. And that turbulence is what part of what creates the drag that hurts your fuel economy.

Well, by utilizing the wheel cover, reducing that turbulence, we improve fuel economy, but at the same time, it’s that turbulence that grabs the water during the rain and on a wet road that increases slash and spray coming out of an 18 wheeler, for example. So while it doesn’t eliminate splash and spray, it certainly helps to reduce it.

Jamie Irvine:

You’ve been watching The Heavy-Duty Parts Report. My name is Jamie Irvine. Today we’ve been speaking with David Black, VP of fleet sales at Flow Below. To learn more, go to flowbelow.com. David, thank you so much for being my guest today. I really appreciate it.

David Black:

Thank you very much. Appreciate the time.

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